Title of Invention
TITANIUM-CONTAININGGRANULAR POWDERANDMETHOD FOR PRODUCTION
THEREOF, AND EXHAUST GAS TREATMENT CATALYST USING SAME AND
METHOD FOR PRODUCTION THEREOF
Technical Field
[OOOl]
The present invention relates to titanium-containing
granular powder for producing a catalyst for treating exhaust
gas, the titanium-containing granular powder having good
moldability into a honeycomb structure, a catalyst for
treating exhaust gas using the same, and methods for producing
them.
Background Art
[0002]
Exhaust gas emitted fromthermal electric power plants,
various factories, waste incineration plants and the like
contains nitrogen oxides and the like, which cause
photochemical smog. Accordingly, various proposals havebeen
made for exhaust gas denitration technique for removing
nitrogen oxides from exhaust gas. On example of the e,xhaust
gas denitration techniques that are widely employed is a
selective catalytic reduction (SCR) method, in which ammonia
is injected to exhaust gas, which is then made in contact with
a catalyst, thereby decomposing nitrogen oxides into nitrogen
gas and water. The SCR method uses a catalyst containing a
titanium oxide support having supported thereon an active
ingredient, such as vanadium oxide and tungsten oxide. In
general, the denitration catalyst for the SCR method is
disposedinside the flueandismade incontact withthe exhaust
gas to perform the denitration reaction, and for preventing
the pressure loss in the flue from being increased and for
increasing the contact area with the exhaust gas, the
nitrification catalyst is used after molding, for example,
into a honeycomb form.
A denitration catalyst in a honeycomb form is produced,
for example, byamethodof extrusion-molding a powder support
ingredient into a honeycomb form, and then impregnating or
supporting an active ingredient thereon, and a method of
kneading a support ingredient and an active ingredient with
a molding assistant, and then extrusion-molding them into a
honeycomb form. Accordingly, titanium oxide powder used as
the support ingredient preferably has good extrusion
moldability. Titanium oxide powder that is calcined at a
relatively high temperature has good extrusion moldability,
but the crystallization thereof proceeds to decrease the
specific surface area, and the denitration capabilitythereof
maybe deterioratedin some cases. ~itaniumoxidep owder that
is calcined at a relatively low temperature suffers less
decrease of the specific surface area, but has a problem that
it may be difficult to form into a honeycomb form due to poor
extrusion moldability.
[0003]
PTLldescribes atechnique of preparing composite oxide
particles of titanium dioxide and tungsten oxide by adding
ammonium paratungstate to a titanium dioxide precursor and
calcining at 500°C for 3 hours, and PTL 2 provides
titanium-containing powder for producing a denitration
catalyst by adding ammonium paratungstate and ammonium
metavanadate to a titaniumdioxide precursor and calcining at
500°C for2hours. However, it hasbeen knownthat, for example,
ammonium paratungstate is decomposed at a temperature of
approximately 450°C while releasing ammonia, and becomes
tungsten oxide consequently. Therefore, the
titanium-containing powder for producing a denitration
catalyst described in PTLs 1 and 2 contains no ammonium salt,
and thus in the production of a honeycomb structure by using
these kinds of powders, the extrusion moldability thereof may
not be good.
PTL 3 describes a catalyst for treating exhaust gas with
a technique of providing a denitration catalyst by adding
ammoniummetatungstate to titanium dioxide powder calcined at
from 600 to l,OOO°C, shaping the resultant into a
honeycomb-form, and further calcining atatemperature of from
500 to 600°C. However, the calcination of titanium dioxide
powder at from 600 to 1, OOO°C promotes crystallization, which
decreases the specific surface area of the powder, and the
denitration catalyst activity may be decreased consequently.
Citation List
Patent Literatures
[0004]
PTL 1
JP-A-10-235206
PTL 2
JP-A-11-226360
PTL 3
JP-A-9-47637
Summary of Invention
Technical Problem
[OOOS]
The invention has been developed in view of the
circumstances, and an object thereof is to provide
titanium-containing granular powder that has goodmoldability
and suffers less decrease in specific surface area after
calcination, a method for producing the same, a honeycomb
catalyst for treating exhaust gas containing the
titanium-containing granular powder, and a method for
producing the same.
Solution to Problem
[0006]
The first invention is titanium-containing granular
powder forproducingahoneycomb catalyst fortreatingexhaust
gas, containing (X) a composite oxide of metallic elements
containing at least one of tungsten and molybdenum, and
titanium, and (Y) an additive selected from (i) a
tungsten-containing nitrogen compound, (ii) a
tungsten-containing sulfur compound, (iii) a
tungsten-containing chlorine compound, (iv) a
molybdenum-containing nitrogen compound, (v) a
molybdenum-containing sulfur compound and (vi) a
molybdenum-containing chlorine compound,
(1) in the case where the additive (Y) contains the
tungsten-containing nitrogen compound (i) or the
molybdenum-containing nitrogen compound (iv), a molar ratio
(B/A) being in a range of from 8.70 x lo-' to 2.78 x lo-', wherein
A represents a molar number of titanium atoms contained in the
titanium-containing granular powder, and B represents amolar
number of nitrogen atoms contained in the titanium-containing
granular powder,
(2) in the case where the additive (Y) contains the
tungsten-containing sulfur compound (ii) or the
molybdenum-containing sulfur compound (v), amolar ratio (C/A)
being in a range of from 6.96 x to 5.55 x lo-', wherein
A represents a molar number of titanium atoms contained in the
titanium-containing granular powder, and C represents amolar
number of sulfur atoms contained in the titanium-containing
granular powder, and
(3) in the case where the additive (Y) contains the
tungsten-containing chlorine compound (iii) or the
molybdenum-containing chlorine compound (vi), a molar ratio
(D/A) being in a range of from 6.96 x to 6.94 x lo-', wherein
A represents a molar number of titanium atoms contained in the
titanium-containing granular powder, and D represents amolar
number of chlorine atoms contained in the titanium-containing
granular powder.
The first invention preferably satisfies the following
conditions.
(a) On measuring the titanium-containing granular
powder by X-ray diffractiometry, titanium oxide contained in
the titanium-containing granular powder has an anatase
crystalline structure, a peak intensity ratio (pl/pO) is in
a range of from 0.30 to 1.3, wherein P' represents a peak
intensity of a (101) plane of the anatase crystal, and PO
represents a peak intensity of a (101) plane of an anatase
crystal of standard powder of titanium dioxide (MC-90,
produced by Ishihara Sangyo Kaisha, Ltd.), and the
titanium-containing granular powder has a specific surface
area in a range of from 40 to 300 m2/g.
(b) The titanium-containing granular powder contains
the granular substance that has a particle diameter of 45 p
or less in an amount of 99.9% by weight or more based on the
total amount thereof.
(c) The tungsten-containing nitrogen compound (i) is at
least one selected from ammonium paratungstate, ammonium
metatungstate, ammonium phosphotungstate and ammonium
tetrathiotungstate, and the molybdenum-containing nitrogen
compound (iv) is at least one selectedfromammoniummolybdate,
ammonium phosphomolybdate and ammonium tetrathiomolybdate.
(d) The tungsten-containing sulfur compound (ii) is
tungsten disulfide, and the molybdenum-containing sulfur
compound (v) is molybdenum disulfide.
(e) The tungsten-containing chlorine compound (iii) is
tungstenhexachloride, andthemolybdenum-containingchlorine
compound (vi) is molybdenum pentachloride.
[0007]
Thesecondinventionisahoneycombcatalystfortreating
exhaust gas, containing the titanium-containing granular
powder and an active ingredient, a content of the
titanium-containing granular powder being 60% by weight or
more.
The second invention preferably satisfiesthe following
conditions.
(a) The active ingredient is vanadium oxide.
(b) The honeycomb catalyst for treating exhaust gas is
a catalyst for removing nitrogen oxides.
[0008]
The third invention is a method for producing
titanium-containing granular powder for producing a honeycomb
catalyst for treating exhaust gas, containing mixing (X) a
composite oxide of metallic elements containing at least one
of tungsten and molybdenum, and titanium, and (Y) an additive
selected from (i) a tungsten-containing nitrogen compound,
(ii) a tungsten-containing sulfur compound, (iii) a
tungsten-containing chlorine compound, (iv) a
molybdenum-containing nitrogen compound, (V a
molybdenum-containing sulfur compound and (vi) a
molybdenum-containing chlorine compound, in the following
ratio:
(1) in the case where the additive (Y) used is the
tungsten-containing nitrogen compound (i) or the
molybdenum-containing nitrogen compound (iv), the method
containingmixingthe composite oxide and the additive tomake
a molar ratio (B/A) in a range of from 8.70 x to 2.78 x
lo-', wherein A represents a molar number of titanium atoms
contained in the titanium-containing granular powder, and B
represents a molar number of nitrogen atoms contained in the
titanium-containing granular powder,
(2) in the case where the additive (Y) used is the
tungsten-containing sulfur compound (ii) or the
molybdenum-containing sulfur compound (v), the method
containingmixingthe composite oxide and the additive tomake
a molar ratio (C/A) in a range of from 6.96 x to 5.55 x
lo-', wherein A represents a molar number of titanium atoms
contained in the titanium-containing granular powder, and C
represents a molar number of sulfur atoms contained in the
titanium-containing granular powder, and
(3) in the case where the additive (Y) used is the
tungsten-containing chlorine compound (iii) or the
molybdenum-containing chlorine compound (vi), the method
containingmixingthe composite oxide and the additive tomake
a molar ratio (D/A) being in a range of from 6.96 x to 6.94
x 10-l~ wherein A represents a molar number of titanium atoms
contained in the titanium-containing granular powder, and D
represents a molar number of chlorine atoms contained in the
titanium-containing granular powder.
The third invention preferably satisfies the following
conditions.
(a) Thetitanium-containing granular powder is obtained
by mixing the composite oxide (X) of metallic elements and at
least one of the additive (Y) selected from (i) a
tungsten-containing nitrogen compound, (ii) a
tungsten-containing sulfur compound, (iii) a
tungsten-containing chlorine compound, (iv) a
molybdenum-containing nitrogen compound, (v) a
molybdenum-containing sulfur compound and (vi) a
molybdenum-containing chlorine compound.
[0009]
The fourth invention is a method for producing a
honeycomb catalyst for treating exhaust gas, containing
(1) mixing the titanium-containing granular powder for
producing a honeycomb catalyst for treating exhaust gas
produced by the production method according to the third
invention, water, and vanadium oxide or a precursor thereof
to prepare a slurry liquid containing these ingredients,
(2) kneading the slurry liquid and a structural
reinforcing material to prepare a mixture,
(3) extrusion-molding themixturetoprepareahoneycomb
structure,
(4) drying the honeycomb structure, and then baking the
honeycomb structure under atemperature condition of from 400
Advantageous Effects of Invention
[OOlO]
The titanium-containing granular powder of the
inventioncontainsacompositeoxideofatleastoneoftungsten
and molybdenum, and titanium, and thus crystallization on
bakingthe catalyst for treating exhaust gas after molding the
honeycomb structuremaybe suppressedfromproceeding, thereby
preventingthe specific surface area frombeing decreased and
maintaining the high catalyst activity. The
titanium-containing granular powder further contains, as an
additive, a nitrogen compound, a sulfur compound or a chlorine
compound containing tungsten or molybdenum, and thus the
additive shows a function of improving the moldability of the
titanium-containing granular powder, thereby providing
consequently a honeycomb structure having substantially no or
a considerably small amount of partial damage of the honeycomb
shape formed in the extrusion molding.
Brief Description of Drawing
[OOll]
[Fig. 11
Fig. 1 is a conceptual illustration of a honeycomb
structure referred in the invention, and more specifically a
plan view thereof viewed from one end of the penetrating
direction of the honeycomb holes.
Description of Embodiments
[0012]
Preferredembodimentsoftheinventionwillbedescribed
in detail below.
Titanium-containing Granular Powder
The titanium-containing granular powder for producing
a honeycomb catalyst for treating exhaust gas in the invention
(which may be hereinafter referred simply to a
titanium-containing granular powder) contains a composite
oxide of metallic elements containing at least one of tungsten
and molybdenum, and titanium.
Thecompositeoxide is acompoundof at least onemetallic
element of tungsten (W) andmolybdenum (Mo), ametallic element
of titanium (Ti) and oxygen (0). For example, an example of
a part of a composite oxide containing titanium(IV),
tungsten(1V) and oxygen is shown by the following general
chemical formula (I) :
The composite oxide contains a crystalline structure
part corresponding to anatase type titanium dioxide.
Specificexamplesofthecompositeoxideincludeabinary
composite oxide, such as a composite oxide containingtitanium
and tungsten (which may be conveniently represented by
Ti04/2-W04/2)a nd a composite oxide containing titanium and
molybdenum (which may be conveniently represented by
Ti04/2-Mo04/2,) and a ternary composite oxide, such as a
composite oxide containing titanium, tungsten and molybdenum
(which may be conveniently represented by
Ti04/2-W04/2-Ti04/2-Mo04/. 2)I t is considered that these binary
and ternary composite oxides have a structure containing
titanium oxide molecules Ti0412 having incorporated therein
WO4/2, M00412 and the like in a highly dispersed state, as shown
in the general chemical formula (I). It is considered that
WO4/2 and Mo0412 incorporated in titanium oxide molecules Ti0412
shows a function of suppressing the progress of
crystallization and the transition to rutile type titanium
dioxide (Ti02) of titanium dioxide (Ti02) on heating and baking
the honeycomb structure obtained fromthetitanium-containing
granular powder containing the composite oxide.
The content of WO4/2 and Moo412 in the composite oxide is
desirably smallerthanthe amount of Ti0412. More specifically,
in terms of the amount of oxides, W03 and Moo3, converted from
W04/2 and M004/2 (provided that Ti0412 is calculated as Ti02) ,
the sole amountortotalamountthereofispreferablyina range
ofmorethanO%bymass and20%bymassorless. Whenthe content
of W04/2 and M004/2 is larger than the amount of Ti0412, the
honeycomb catalyst for treating exhaust gas using the
honeycomb structure obtained from the titanium-containing
granular powder containingthe composite oxidemay not provide
the advantageous effects including the resistance to sulfur
compounds and the like contained in exhaust gas, the abrasion
resistance, and the like, in some cases.
[0013]
The titanium-containing granular powder containing the
composite oxide and the additive described above preferably
has a specific surface area (SA) andapeakintensityofa (101)
plane of the anatase crystal of titanium oxide on measuring
the titanium-containing granular powder by X-ray
diffractiometry that are each in a specific range. The
specific surface area of the titanium-containing granular
powder is preferably in a range of from 40 to 300 m2/g, and
more preferably in a range of from 50 to 120 m2/g. When the
specific surface area is less than 40 m2/g, the honeycomb
structuremoldedwiththetitanium-containing granular powder
has a small specific surface area after baking, and the
sufficient catalyst activity as a catalyst for treating
exhaust gas may not be obtained, and on the other hand, it is
difficult to produce titanium-containing granular powder
having a specific surface area larger than 300 m2/g. The
specific surface area of the titanium-containing granular
powder may be controlled within the aforementioned range by
heating or calcining the granular powder. However, the
granular powder may not be heated to a temperature, at which
the additive used is decomposed to release a gaseous nitrogen
compound (such as N H 4 ) , a gaseous sulfur compound (such as SOZ)
or a gaseous chlorine compound (such as C102). For example,
inthecasewherearnmoniumparatungstateisusedasthe additive,
the compoundis decomposedto release ammonia at approximately
450°C, and thus the granular powder may not be heated to that
temperatureorhigher. Inthecasewhereahoneycomb structure
is tried to be molded with the titanium-containing granular
powder, in which the additives release the gaseous nitrogen
compound, the gaseous sulfur compound, the gaseous chlorine
compound and the like, the moldability of the honeycomb
structure may be disadvantageously deteriorated.
The peak intensity ratio (pl/pO)i s preferably in a range
of from 0.30 to 1.3, and more preferably in a range of from
0.6 to 1.2, wherein P1 represents the peak intensity of the
(101) plane of the anatase crystal contained in the
titanium-containing granular powder, and PO represents a peak
intensity of a (101) plane of an anatase crystal of standard
powderoftitaniumdioxide (MC-90, producedby Ishihara Sangyo
Kaisha, Ltd.). Whenthepeakintensityexceeds 1.3, the value
shows that the crystallization of titanium dioxide proceeds,
which may result in deterioration of the specific surface area
and the catalyst capability. It is difficult to produce
titanium-containing granular powder having a peak intensity
that is lower than 0.30. The peak intensity ratio is further
preferablyinarangeoffrom0.9tol.l. T h e e f f e c t of a d d i t i o n
of the a d d i t i v e on the moldability may be maximally e x h i b i t e d
within the range. The peak i n t e n s i t y r a t i o (pl/pO) may be
c o n t r o l l e d within the range by heating or c a l c i n i n g the
granular powder. However, as s i m i l a r t o the above, the
granular powder shouldnotbeheatedtoatemperature, a t which
the a d d i t i v e used is decomposed t o r e l e a s e a gaseous nitrogen
compound (such as NH4) , a gaseous s u l f u r compound (such as S02)
or a gaseous c h l o r i n e compound (such as C 1 0 2 ) . The reason
t h e r e f o r is as described above.
[0014]
The titanium-containing granular powder according t o
the embodiment contains an a d d i t i v e f o r enhancing the
moldability on molding i n t o a honeycomb s t r u c t u r e . The
a d d i t i v e shows a f u n c t i o n of imparting a s u i t a b l e v i s c o s i t y
t o a kneaded product of the titanium-containing granular
powderprepared f o r extrusionmolding. The s u i t a b l e v i s c o s i t y
imparted t o the kneaded product prevents t h e kneaded product
f r o m b e i n g i n t e r r u p t e d o n f e e d i n g t o a d i e o f a v a c u u m e x t r u s i o n
moldingmachine or t h e l i k e , and thereby a honeycomb s t r u c t u r e
having s u b s t a n t i a l l y no or a considerably s m a l l amount of
p a r t i a l damage of the honeycomb shape may be molded. The
language " p a r t i a l damage of t h e honeycomb shape" herein means
t h a t the walls c o n s t i t u t i n g the honeycomb s t r u c t u r e a r e
p a r t i a l l y damaged as shown, f o r example, i n Fig. 1, and may
be referred simply to "honeycomb damage" in some cases. he
honeycomb structure maybe decreased in specific surface area
o r m a y b e d e c r e a s e d i n m e c h a n i ~ a l ~ t r e n g t h t h e r e b yI. ngeneral,
even when partial damage of the honeycomb shape occurs during
molding in a vacuum extrusion molding machine, the extrusion
molding proceeds unchanged, and therefore it is necessarythat
the extrusion molding machine is stopped, and the defective
product is discarded. In the titanium-containing granular
powder according to the invention, accordingly, an additive
that prevents the honeycomb damage from occurring is added to
the granular powder.
[0015]
The additive added to the titanium-containing granular
powder is selected from the group of additives consisting of
a tungsten-containing nitrogen compound, a
tungsten-containing sulfur compound, a tungsten-containing
chlorine compound, amolybdenum-containingnitrogen compound,
a molybdenum-containing sulfur compound and a
molybdenum-containing chlorine compound.
Examples of the tungsten-containing nitrogen compound
include an ammonium salt of tungstic acid, such as ammonium
paratungstate, ammonium metatungstate, ammonium
phosphotungstate and ammonium tetrathiotungstate, and
examples of the tungsten-containing sulfur compound include
tungsten disulfide and tungsten trisulfide. Examples of the
tungsten-containing chlorine compound include tungsten
hexachloride, tungsten dichloride, tungsten trichloride,
tungsten tetrachloride, tungsten pentachloride, tungsten
dichloride dioxide and tungsten tetrachloride oxide.
Examples ofthemolybdenum-containingnitrogen compound
include an ammonium salt of molybdic acid, such as ammonium
molybdate, ammonium phosphomolybdate and ammonium
tetrathiomolybdate, andexamples ofthemolybdenum-containing
sulfur compound include molybdenum disulfide, molybdenum
trisulfide and molybdenum tetrasulfide. Examples of the
molybdenum-containing chlorine compound include molybdenum
pentachloride, molybdenumdichloride, molybdenumtrichloride,
molybdenum tetrachloride and molybdenum pentachloride
trioxide .
The additive is oxidized to form tungsten oxide (W03)
or molybdenum oxide (Moo3), on baking the molded honeycomb
structure to provide a catalyst for treating exhaust gas.
Tungsten oxide andmolybdenum oxide thus formed are contained
inthe compositeoxideandfurthermoreisdifferentinchemical
combination mode from WO4/*, M00412 and the like incorporated
into titanium dioxide (Ti0412). However, it may be considered
that the additive contributes to suppression of
crystallizationoftitaniumdioxide onbakingthe catalyst for
treating exhaust gas, which causes decrease of the specific
surface area and decrease of the catalyst activity, in
combination with the function of W04/2, M00412 and the like
contained in the composite oxide.
[0016]
The titanium-containing granular powder according to
the invention desirably contains the additive in the ratios
shown below.
In the case where the additive contains the
tungsten-containing nitrogen compound or the
molybdenum-containing nitrogen compound, the molar ratio
(B/A) is preferably in a range of from 8.70 x to 2.78 x
lo-', wherein A represents a value obtained by dividing the
mass of titanium atoms contained in the titanium-containing
granular powder by the atomic weight thereof, andB represents
a value obtained by dividing the mass of nitrogen atoms
contained in the titanium-containing granular powder by the
atomic weight thereof.
In the case where the additive contains the
tungsten-containing sulfur compound or the
molybdenum-containing sulfur compound, the molar ratio (C/A)
is preferably in a range of from 6.96 x to 5.55 x lo-',
wherein A represents a value obtained by dividing the mass of
titanium atoms contained in the titanium-containing granular
powder by the atomic weight thereof, and C represents a value
obtained by dividing the mass of sulfur atoms contained in the
titanium-containing granular powder by the atomic weight
thereof.
In the case where the additive contains the
tungsten-containing chlorine compound or the
molybdenum-containing chlorine compound, the molar ratio
(D/A) is preferably in a range of from 6.96 x to 6.94 x
10-l~ wherein A represents a value obtained by dividing the
mass of titanium atoms contained in the titanium-containing
granular powder by the atomic weight thereof, and D represents
a value obtained by dividing the mass of chlorine atoms
contained in the titanium-containing granular powder by the
atomic weight thereof.
whenthecontent oftheadditive is smallerthantherange,
there is a possibility that the honeycomb damage may not be
sufficiently suppressed. When the additive is contained in
an amount that exceeds the range, oxidation of the additive
may cause larger heat generation, which brings about a
possibility of breakage and cracks ofthe honeycomb structure
on baking.
[0017]
The titanium-containing granular powder according to
the invention preferably contains the granular substance that
has a particle diameter of 45 p or less in an amount of 99.9%
by weight or more based on the total amount thereof. When the
amount of the granules having a particle diameter within the
range is smallerthan 99.9% bymass, i-e., a granular substance
having a particle diameter exceeding 45 p is contained in an
amount exceeding 0.1% by mass, a part of the walls or many of
the wallsmaybe damagedonextrusionmolding, thereby failing
to provide the target honeycomb structure in some cases.
[0018]
Method for producing Composite Oxide
An example of a production method of the
titanium-containing granular powder having the features
describedabove will be described. Aproductionmethod ofthe
composite oxide of metallic elements containing at least one
of tungsten and molybdenum, and titanium will be described.
To a titanium-containing solution, such as metatitanic
acid, as a raw material of titanium dioxide, a raw material
that is to be contained in the form of W04/2 or Moo412 finally
in the composite oxide is added to prepare a slurry solution
containing the raw material in an amount of from 5 to 10% by
mass in terms of the amount of oxides, W03 and Moo3. The raw
material used may be the similar substances as the
aforementioned additive. Specifically, the raw material may
be selectedfromatungsten-containingnitrogencompound, such
as ammonium paratungstate, ammonium metatungstate, ammonium
phosphotungstate and ammonium tetrathiotungstate, a
tungsten-containing sulfur compound, such as tungsten
disulfide and tungsten trisulfide, a tungsten-containing
chlorine compound, such as tungsten hexachloride, tungsten
dichloride, tungsten trichloride, tungsten tetrachloride,
tungsten pentachloride, tungsten dichloride dioxide and
tungsten tetrachloride oxide, a molybdenum-containing
nitrogen compound, such as ammonium molybdate, ammonium
phosphomolybdate and ammonium tetrathiomolybdate, a
molybdenum-containing sulfur compound, such as molybdenum
disulfide, molybdenumtrisulfide andmolybdenumtetrasulfide,
and a molybdenum-containing chlorine compound, such as
molybdenum pentachloride, molybdenum dichloride, molybdenum
trichloride, molybdenum tetrachloride and molybdenum
pentachloride trioxide.
The amount of the raw material may be determined, for
example, by comprehending in advance by a preliminary
experiment or the like the relationship between the content
of tungsten or molybdenum in terms of the amount of an oxide,
W03 or Mo03, converted from WO4/2 or M00412 contained in the
dehydrated and calcinedtitanium-containing granular powder,
more specifically the composite oxide, and the amount of the
raw material added.
Itispreferredthatatitaniumsulfatesolutionobtained
in a production process of titanium dioxide by a sulfuric acid
process is used as a raw material of metatitanic acid, and
titanium sulfate is hydrolyzed to provide metatitanic acid.
[0019]
It is preferred that an acid, such as sulfuric acid, or
an alkali, such as ammonia, is added to the resulting solution
containing at least one of tungsten and molybdenum, and
titanium, thereby controlling the pH of the solution to a
prescribed value in a range of from 2 to 10.5.
The slurry solution containing at least one of tungsten
and molybdenum, and titanium, adjusted for pH to a prescribed
value thus obtained is ripened by heating, for example, in a
temperature range of from 50 to 100°C for a period of from 0.5
to 24 hours. The slurry solution thus ripened by heating is
dehydrated, and the resulting dehydrated cake is rinsed with
distillated water or the like and then again dehydrated to
provide a dehydrated cake.
A dried material obtained by drying to remove water in
the dehydrated cake is calcined in a kiln or the like in the
atmosphere, for example, in a temperature range of from 400
to 700°c for a period of from 0.5 to 20 hours, thereby providing
the composite oxide.
In the invention, it is preferred that the composite
oxide is pulverized depending on necessity with a ball mill
or the like, thereby providingthe composite oxide containing
the composite oxide that has a particle diameter of 45 pm or
less in an amount of 99.9% by weight or more based on the total
amount thereof.
[0020]
Method for producing Titanium-containing Granular Powder
Withthe composite oxideofmetallic elements containing
at least one of tungsten and molybdenum, and titanium thus
produced by the aforementioned method, the additive selected
from a tungsten-containing nitrogen compound, a
tungsten-containing sulfur compound, a tungsten-containing
chlorine compound, amolybdenum-containingnitrogencompound,
a molybdenum-containing sulfur compound and a
molybdenum-containing chlorine compound is mixed to produce
the titanium-containing granular powder according to the
invention.
Specifically, in the case where the additive used is the
tungsten-containing nitrogen compound or the
molybdenum-containing nitrogen compound, the composite oxide
and the additive are mixed in a ratio that provides the molar
ratio (B/A) in a range of from 8.70 x to 2.78 x lo-', wherein
A represents a value obtained by dividing the mass of titanium
atoms containedinthe titanium-containing granular powder by
the atomic weight thereof, and B represents a value obtained
by dividing the mass of nitrogen atoms contained in the
titanium-containing granular powder by the atomic weight
thereof. For example, the amount of the additive mixed may
be obtainedin suchamannerthatthe relationshipofthe ratios
B/A of the composite oxide and the titanium-containing
granularpowderwithrespecttotheamountoftheadditiveadded
is formulated, by which the necessary amount of the additive
to be added is calculated back from the design value of the
ratio B/A.
[0021]
In the case where the additive contains the
tungsten-containing sulfur compound or the
molybdenum-containing sulfur compound, the composite oxide
and the additive are mixed in a ratio that provides the molar
ratio (C/A) in a range of from 6.96 x lo-' to 5.55 x lo-', wherein
A represents a value obtained by dividing the mass of titanium
atoms containedinthe titanium-containing granular powder by
the atomic weight thereof, and C represents a value obtained
by dividing the mass of sulfur atoms contained in the
titanium-containing granular powder by the atomic weight
thereof. The amount of the additive mixed in this case may
also be obtained, for example, from the relationship of the
ratios C/A of the composite oxide and the titanium-containing
granular powder with respect to the amount of the additive
added.
In the case where the additive contains the
tungsten-containing chlorine compound or the
molybdenum-containing chlorine compound, the composite oxide
and the additive are mixed in a ratio that provides the molar
ratio (D/A) in a range of from 6.96 x loe3 to 6.94 x lo-', wherein
A represents a value obtained by dividing the mass of titanium
atoms containedinthetitanium-containing granular powder by
the atomic weight thereof, and D represents a value obtained
by dividing the mass of chlorine atoms contained in the
titanium-containing granular powder by the atomic weight
thereof. The amount of the additive mixed in this case may
also be obtained, for example, from the relationship of the
ratios D/A of the composite oxide and the titanium-containing
granular powder with respect to the amount of the additive
added.
[0022]
For the additive used for preparing the
titanium-containing granular powder, only one kind may be
selected from the group of additives, or two or more kinds may
be selected therefrom. The timing of the addition of the
additive tothe compositeoxide isnot limitedtothe stepafter
the pulverization of the composite oxide. For example, the
additivemaybe placedin aballmill with the composite oxide,
and they may be pulverized simultaneously.
The titanium-containing granular powder preferably
contains the granular substance that has a particle diameter
of 45 p n or less in an amount of 99.9% by weight or more based
on the total amount thereof. As the method for preparing the
titanium-containing granular powder having a particle
diameter in the range, the composite oxide and the additive
that have been pulverized in advance with a ball mill or the
like into granular substances containing the substances that
have a particle diameter of 45 p or less in an amount of 99.9%
by weight or more may be mixed, or the composite oxide and the
additive may be mixed and then pulverized to provide the
particle diameter within the range.
[0023]
Honeycomb Catalyst for treating Exhaust Gas
The honeycomb catalyst for treating exhaust gas
according to the invention is a catalyst for treating exhaust
gas formedofthe honeycomb structure, andpreferablycontains
the titanium-containing granular powder in an amount range of
60% by mass or more, and more preferably from 70 to 99.9% by
mass, based on the total weight. In the case where the content
of the titanium-containing granular powder is less than 60%
by mass, a target denitration activity may not be obtained in
some cases. Granular powder that does not contain the
composite oxide and the additive in the invention and thus is
outside the technical scope of the invention (for example,
titanium dioxide powder) may be contained in an amount of less
than 40% by mass when the titanium-containing granular powder
of the invention is contained in an amount of 60% by mass or
more.
The honeycomb catalyst for treating exhaust gas further
contains an active ingredient for removing nitrogen oxides.
Examplesoftheactiveingredientincludemetalliccomponents,
such as vanadium ( V ) , tungsten (W) , molybdenum (Mo) , chromium
(Cr), manganese (Mn), iron (Fe), nickel (Nil, copper (Cu) I
silver (Ag) , iron (Au) , palladium (Pd) , yttrium (Y) , cerium
(Ce) , neodymium (Nd) , indium (In) and iridium (Ir) .
Among the active ingredients, vanadium oxide (V205) may
be preferably used due to the relatively inexpensiveness and
the high removal rate of nitrogen oxides. The content of the
active ingredient used in the catalyst for treating exhaust
gas for removing nitrogen oxides is preferably in a range of
from 0.1 to 30% by mass in terms of metal oxide based on the
total weight of the catalyst.
The honeycomb catalyst for treating exhaust gas that is
molded with 60% by mass or more of the titanium-containing
granular powder containing the composite oxide not only is
suppressedin progress of crystallization of titaniumdioxide
on baking the honeycomb structure containing the active
ingredient, but also achieves a high removal rate of nitrogen
oxides on treating exhaust gas therewith.
[0024]
In the titanium-containing granular powder of the
invention, titanium oxide (Ti0412) contained in the granular
powder forms a composite oxide with W04/2 and/or Moo412 and the
like, and thus the crystallization of titanium dioxide may be
suppressed from occurring even on calcining at the
aforementioned temperature.
The titanium-containing granular powder not only
contains tungsten, such as w04/2ro r molybdenum, such as M004/2,
in the composite oxide, but also containsthe rawmaterial that
finally becomes an oxide, such as W03 and Mo03, on baking in
the additive used for enhancing the moldability on extrusion
molding. Accordingly, on baking the honeycomb structure
molded with the titanium-containing granular powder,
crystallization of titanium dioxide may be prevented to
suppress the specific surface area frombeing decreased. The
honeycomb catalyst for treating exhaust gas having been
suppressedincrystallizationoftitaniumdioxideisdifficult
to be decreased in the specific surface area thereof and
maintainsthedenitrationactivitythatis close tothe initial
activity for a prolonged period of time. The additive used
in the invention enhancesthemoldabilityonextrusionmolding
of the honeycomb structure, and thus suppresses the honeycomb
damage described above from occurring.
[0025]
Method for producing Honeycomb Catalyst for treating Exhaust
Gas
The honeycomb catalyst for treating exhaust gas
according to the invention may be produced by (a) a method,
in which the titanium-containing granular powder of the
invention and the active ingredient or a precursor thereof are
kneaded with a molding assistant to prepare a kneaded product,
which is then extrusion-molded into a honeycomb form, dried
and baked (kneading method), (b) a method, in which the
titanium-containing granular powder of the invention is
kneaded with a molding assistant to prepare a kneaded product,
which is then extrusion-molded into a honeycomb form, dried
and baked to prepare a support, and the support is impregnated
with an aqueous solution containing the active ingredient,
followed by drying and baking (impregnation method), or the
like.
Inparticular, acatalystproducedbythe kneadingmethod
(a) is called as a solid type catalyst, which provides high
denitration activity, and thus as an example thereof,
production of a honeycomb catalyst for treating exhaust gas
containing vanadium oxide as the active ingredient by the
kneading method will be described.
Thetitanium-containing granular powder is dispersed in
a solvent, such as water, to prepare a slurry solution, and
a precursor of vanadium oxide, such as ammonium vanadate, and
monoethanolamine as a solubilizing agent are added to the
slurry solution. Areinforcingmaterial, such as glass fibers
or acid clay, and a lubricant, such as polyethylene oxide, are
further added to the slurry solution, which is kneaded with
a kneading device, such as a kneader, to prepare a kneaded
product suitable for extrusion molding.
The kneaded product thus obtained is extrusion-molded,
for example, with a vacuum extrusion molding machine, thereby
providing a honeycomb s t r u c t u r e . A t t h i s t i m e , t h e a d d i t i v e
c o n t a i n e d i n t h e kneadedproduct imparts a s u i t a b l e v i s c o s i t y
t o t h e kneaded product, and thereby t h e kneaded product fed
t o a die of t h e vacuum e x t r u s i o n molding machine is prevented
from being i n t e r r u p t e d , thereby molding a honeycomb s t r u c t u r e
having s u b s t a n t i a l l y no o r a c o n s i d e r a b l y s m a l l amount of
p a r t i a l damage of t h e honeycomb shape. Thereafter, t h e
r e s u l t i n g honeycomb s t r u c t u r e is d r i e d , and t h e d r i e d
honeycomb s t r u c t u r e is baked i n a k i l n o r t h e l i k e i n t h e
atmosphere, f o r example, i n a temperature range o f from 400
to700°C f o r a p e r i o d o f f r o m 0 . 5 t o 2 4 hours, t h e r e b y p r o v i d i n g
a honeycomb c a t a l y s t f o r t r e a t i n g exhaust g a s c o n t a i n i n g
t i t a n i u m oxide having g l a s s f i b e r s o r a c i d c l a y added t h e r e t o
containing vanadium oxide a s an a c t i v e metal.
[0026]
In general, it has been known t h a t on baking a t i t a n i u m
oxide s u p p o r t ( f o r example, a honeycomb s t r u c t u r e ) having
vanadium oxide a s an a c t i v e i n g r e d i e n t o r a p r e c u r s o r t h e r e o f
added or having a suspension aqueous s o l u t i o n t h e r e o f
impregnated, c r y s t a l l i z a t i o n of t i t a n i u m oxide proceeds due
tothepresenceofvanadium. I n t h e p r o d u c t i o n o f t h e c a t a l y s t
f o r t r e a t i n g exhaust gas of t h e i n v e n t i o n , a c c o r d i n g l y , t h e
titanium-containing granular powder t h a t is obtained by
calciningwithouttheadditionofvanadiumoxideoraprecursor
t h e r e o f ( i n c l u d i n g a suspension aqueous s o l u t i o n t h e r e o f ) is
used. In this point of view, it is not preferred to add the
vanadium source in the calcination step of the
titanium-containing granular powder, and it is preferred to
bake the catalyst precursor (honeycomb structure) containing
the vanadium source. Even in the case where the catalyst
precursor containing the vanadium source is baked, the
catalyst precursor that is prepared with the
titanium-containing granular powder of the invention may be
sufficiently suppressed in the extent of progress of
crystallization of titanium dioxide due to the aforementioned
mechanisms.
The shape ofthe honeycomb catalyst fortreatingexhaust
gas ( e . , the honeycomb structure) is not particularly
limited, and may be formed of a square column, a rectangular
columnor the like, andplural rectangular honeycombholes (for
example, from 4 to 2,500 holes) are formed on the plane viewed
fromoneendofthepenetratingdirectionofthehoneycombholes
as shown in Fig. 1. The honeycomb hole may not be in a
rectangular shape but may be in a hexagonal shape or the like.
The external dimension of the honeycomb structure preferably
has (1) a length in the plane from one end in the penetrating
direction of the honeycomb hole (which may be hereinafter
referred to as a "length of one edge in the plane") of
approximately from 30 to 300 mm, and preferably approximately
from 50 to 200 mrn, (ii) a length of the honeycomb hole in the
penetrating direction (which may be hereinafter referred to
as a "length in the penetrating direction") of approximately
from 100 to 3,000 rnm, and preferably approximately from 300
to 1,500 mm, (iii) a length of one edge of an opening forming
the honeycomb hole (in a rectangular shape) (which may be
hereinafter referred to as an "aperture") of approximately
from 1 to 15 mm, and preferably approximately from 2 to 10 mm,
(iv) a thickness of walls formed among the honeycomb holes
(whichmaybehereinafterreferredtoasa"thicknessofwa11s")
ofapproximatelyfrom0.1to2mm, andpreferablyapproximately
from 0.1 to 1.5 mm, and (v) an aperture ratio of the honeycomb
structure of from 60 to 85%, and preferably from 70 to 85%.
In the case where the external dimension of the honeycomb
structure having a rectangular column shape deviates fromthe
aforementioned dimensional ranges, there are some cases where
the honeycomb structure is difficult to mold, the honeycomb
structure is deteriorated in strength, and the denitration
activity and the decomposition activity for organic halogen
compounds per unit volume are lowered.
[0027]
Method of using Honeycomb Catalyst for treating Exhaust Gas
The honeycomb catalyst for treating exhaust gas of the
invention may be favorably applied to a NO, removal method
performing catalytic reduction of exhaust gas containing NO,
and SO,, such as exhaust gas containing NOxf particularly a
boiler exhaust gas, and also the exhaust gas that further
contains heavy metals and dusts, by adding a reducing agent,
suchasammonia. The conditions, underwhichthecatalystused,
may be ordinary conditions for denitration treatment, and
specifically it is preferred that the reaction temperature is
in a range of from 150 to 60O0C, and preferably from 300 to
400°C, and the space velocity (superficial velocity) is in a
range of from 1,000 to 100,000 hr-l.
Example
[0028]
Evaluation Methods
The evaluation methods of the honeycomb catalyst for
treating exhaust gas produced with titanium-containing
granular powder of the examples are shown below.
(1) Moldability Test (Formation of Honeycomb Damage)
The determination standard of the moldability of the
honeycomb structure was as follows. 20 pieces of honeycomb
structures in a rectangular column shape having a length in
the penetrating direction of 500 mm (length of one edge in
plane: approximately 75 mrn, length of one edge of honeycomb
hole: approximately 6.7 mm, thickness of walls of honeycomb
hole: approximately 0.75 mm) were continuously molded with a
vacuum extrusion molding machine, and the number of the first
honeycomb structure that suffered partial damage of the
honeycomb shape was determined.
(2) Abrasion Resistance
A honeycomb catalyst for treating exhaust gas formed of
a honeycomb structure having 9 x 9 of honeycomb holes and a
l e n g t h i n t h e p e n e t r a t i n g d i r e c t i o n o f 1 0 0 m m (catalystshaving
other dimensions were cut into this dimension) was used as a
test specimen, and the test specimen was filled in a flow
reactor. Gas containing sand was passed through the flow
reactor under the following conditions, and the abrasion rate
was measured from the weight reduction of the catalyst weight
bythe following expression (1). The amount ofthe sandpassed
through the flow reactor was obtained by providing a cyclone
as the subsequent stage of the flow reactor, and measuring the
weight of the sand that was collected with the cyclone after
completing the abrasion test.
abrasion rate (%/kg) = ((catalyst weight before starting
abrasion test (g) - catalyst weight after completing abrasion
test (g) ) / catalyst weight before starting abrasion test (g) )
x 100 / amount of sand passed (kg) (1)
Test Conditions
Shape of catalyst: 9 x 9 honeycomb holes, 100 rnm in length
Gas flow rate: 16.5 f 2 m/s (catalyst cross section)
Gas temperature: room temperature 25OC
Gas flow time: 3 hours
Sand concentration: 40 f 5 g/~rn~
Sand: silica sand (average particle diameter: 500 pm)
(3) Heat Resistance Test
The heat resistance was determined by the ratio (peak
intensity PI' after heat resistance test / peak intensity PI
before heat resistance test), wherein I?' represents the peak
intensity of the (101) plane of the anatase crystal contained
in the honeycomb catalyst for treating exhaust gas, and PI'
representsthepeakintensityofthe (101) planeofthe anatase
crystal aftermaintainingthe honeycomb catalyst for treating
exhaust gas in the air at 700°C for 50 hours. A smaller value
of the peak intensity ratio means a smaller increase of the
anatase crystal after the heat resistance test, which means
a catalyst for treating exhaust gas having higher heat
resistance.
[0029]
(4) Specific Surface Area
The titanium-containing granular powder or the
honeycomb catalyst for treating exhaust gas was measured for
the specific surface area with a specific surface area
measuring device (Macsorb HMModel-1220, producedby Mountech
Co,. Ltd.) based on a BET method with a mixed gas of 30% of
nitrogen and 70% of helium as an adsorption gas.
(5) Pore Volume
The honeycomb catalyst for treating exhaust gas was
measured for total pore volumebymercurypress-inmethod with
a porosimeter (Poremaster 33, produced by Quantachrome
Instruments).
(6) X-ray Diffractiometry
The peak intensity PO (the measured value was stored)
of the (101) plane of the anatase crystal of titanium dioxide
(MC-90, producedby IshiharaSangyoKaisha, Ltd.) thatwasused
as the standard powder in the invention and the peak intensity
P' of the (101) plane of the anatase crystal of titanium oxide
containedinthetitanium-containing granularpowder prepared
according to the invention were measured with an X-ray
diffractiometer (RINT1400, produced by Rigaku Corporation),
and the peak intensity ratio (pl/pO) was obtained.
[0030]
(7) Denitration Test
A honeycomb catalyst for treating exhaust gas formed of
a honeycomb structure having 3 x 3 of honeycomb holes and a
l e n g t h i n t h e p e n e t r a t i n g d i r e c t i o n o f 3 0 0 m m (catalysts having
other dimensions were cut into this dimension) was used as a
test specimen, and the test specimen was filled in a flow
reactor. The model gas having the following composition was
passed through the flow reactor, and the denitration rate was
measured. The denitration rate of nitrogen oxides (NO,) in
the gas before and after contacting with the catalyst was
obtained by the following expression (2). The concentration
of NO, was measured with a chemiluminescent nitrogen oxide
analyzer (ECL-88A0, produced by Anatec Yanaco Corporation).
denitration rate ( % ) = ( (NO, in gas before contact (ppm by mass)
- NO, in gas after contact (ppm by mass)) / NOx in gas before
contact (ppm by mass)) x 100 (2)
Test Conditions
Shape of catalyst: 3 x 3 honeycomb holes, 300 mrn in length
Reaction temperature: 380°C
Superficial velocity (SV) : 20,000 hr-'
Composition of model gas: NOx = 180 pprn by mass, NH3 = 180 pprn
by mass, SO2 = 500 pprn by mass, 02 = 2% by weight, H20 = 10%
by weight, N2 = balance
[0031]
Example 1
Titanium-containing Granular Powder (a) and Honeycomb
Catalyst for treating Exhaust Gas (A)
(1) Titanium-containing Granular Powder (a)
A titanium sulfate solution obtained in a production
process of titanium dioxide by a sulfuric acid process was
thermally hydrolyzed to provide a metatitanic acid slurry.
The metatitanic acid slurry in an amount of 23.8 kg in terms
of titanium dioxide was placed in a stirring vessel equipped
witha refluxcondenser, inwhich15 kgof15% byweight aqueous
ammoniahadbeenplacedinadvance, towhich1.13 kgofammonium
paratungstate was further added, and then the mixture was
ripened by heating to 95OC for 1 hour under sufficiently
stirring. The slurry thus ripened by heating was cooled and
taken out from the stirring vessel, and the solid content
thereof was filtered and dehydrated to provide a washed cake.
ThewashedcakewasdriedatatemperatureofllO°C for20hours,
and then calcined at a temperature of 550°C for 5 hours.
According to the procedure, nitrogen atoms contained in the
raw materials added and the like were discharged as ammonia
outside the system. The calcined product was pulverized with
aballmilltoprovide granularpowder (a') ofacomposite oxide
containing metallic elements of titanium and tungsten, the
granular powder (a') having a particle diameter of 45 p or
less in an amount of 99.9% by weight or more based on the total
amount thereof.
0.282 kg of ammonium paratungstate as an additive was
added to the granular powder of a composite oxide (a'), and
they were mixed homogeneously to prepare titanium-containing
granularpowder (a). Thetitanium-containinggranularpowder
thus prepared was pulverized with a ball mill to provide
titanium-containing granular powder (a) containing the
granular powder that had a particle diameter of 45 p or less
inanamount of 99.9%byweightormorebasedonthetotalamount
thereof.
The value Awas obtainedby dividingthemass of titanium
atoms, which were a metallic element constituting the
composite oxide, contained in the titanium-containing
granular powder (a) by the atomicweight thereof, andthevalue
B was obtained by dividing the mass of nitrogen atoms, which
were an element constituting the additive ( e . ammonium
paratungstate), by the atomic weight thereof. As a result,
the values A and B were 297 and 0.90, respectively, and the
ratio (B/A) was 3.03 x
The titanium-containing granular powder (a) was
subjected to X-ray diffractiometry as described above. As a
result, titanium oxide contained in the titanium-containing
granular powder had an anatase crystalline structure, and the
peak intensity ratio (pl/pO)w as 0.97, wherein P' represents
the peak intensity of the (101) plane of the anatase crystal,
and PO represents the peak intensity of the (101) plane of the
anatase crystal of the standard powder of titanium dioxide
(MC-90, produced by Ishihara Sangyo Kaisha, Ltd.). The
specific surface area of the titanium-containing granular
powder measured by the method described above was 93 m2/g.
( 2 ) Honeycomb Catalyst for treating Exhaust Gas (A)
Subsequently, to 23.6 kg of the titanium-containing
granular powder ( a ) thus obtained, a s o l u t i o n c o n t a i n i n g 0.174
kg ammonium metavanadate d i s s o l v e d i n 0.250 kg of
monoethanolamine was added, and thenaqueous ammonia andwater
were added t h e r e t o t o make pH of t h e mixed s l u r r y t o 6 o r more.
1.25 kg of g l a s s f i b e r s ( h e r e i n a f t e r r e f e r r e d t o a s GF i n some
cases) as a r e i n f o r c i n g m a t e r i a l and 0.500 kg of polyethylene
oxide were added t o t h e mixed s l u r r y , which was then heated
andkneadedwitha k n e a d e r t o p r e p a r e a k n e a d e d p r o d u c t s u i t a b l e
f o r e x t r u s i o n molding. The kneaded product was then
extrusion-molded with a vacuum e x t r u s i o n molding machine,
thereby providing a honeycomb s t r u c t u r e having an e x t e r n a l
d i m e n s i o n o f a l e n g t h o f o n e edge i n t h e p l a n e o f 75mm, a l e n g t h
i n t h e p e n e t r a t i n g d i r e c t i o n of approximately 500 mm, an
a p e r t u r e (diameter of p e n e t r a t i n g holes i n a r e c t a n g u l a r
shape) of 6.7 mm, a t h i c k n e s s of walls of 0.75 mm, and an
a p e r t u r e r a t i o of 80%. The honeycomb s t r u c t u r e thus obtained
was d r i e d a t 60°C f o r 24 hours and baked a t 600°C f o r 3 hours,
t h e r e b y p r e p a r i n g a honeycomb c a t a l y s t f o r t r e a t i n g exhaust
gas (A) having a weight compositional r a t i o of t h e m e t a l l i c
elements contained i n t h e honeycomb s t r u c t u r e i n t e r m s of
oxides of TiO2/WO3/~,O5/GE = 89.8/4.73/0.50/5.00.
[0032]
Example 2
Titanium-containing Granular Powder (b) and Honeycomb
C a t a l y s t f o r t r e a t i n g Exhaust Gas (B)
(1) Titanium-containing Granular Powder (b)
Granular powder of a composite oxide (b') was obtained
in the same manner as in Example 1 except that the amount of
ammonium paratungstate added in the preparation of the
granular powder (af ) of a composite oxide obtained in Example
1 was changed to 0.845 kg.
Titanium-containing granular powder (b) was prepared in
the same manner as in Example 1 except that the amount of
ammonium paratungstate added as the additive to the granular
powder of a composite oxide (bf) was changed to 0.564 kg.
Thevalue Awas obtainedbydividingthemass of titanium
atoms, which were a metallic element constituting the
composite oxide, contained in the titanium-containing
granular powder (b) by the atomicweight thereof, andthevalue
B was obtained by dividing the mass of nitrogen atoms, which
were an element constituting the additive i f ammonium
paratungstate), by the atomic weight thereof. As a result,
the values A and B were 297 and 1.80, respectively, and the
ratio (B/A) was 6.06 x
The titanium-containing granular powder (b) was
subjected to X-ray diffractiometry as described above. As a
result, titanium oxide contained in the titanium-containing
granular powder had an anatase crystalline structure, and the
peak intensity ratio (pl/pO) was 0.95. The specific surface
area of the titanium-containing granular powder measured by
the method described above was 94 m2/g.
(2) Honeycomb Catalyst for treating Exhaust Gas (B)
A honeycomb catalyst for treating exhaust gas (B) formed
of the honeycomb structure was prepared in the same manner as
in Example 1 except that the titanium-containing granular
powder (b) was used instead of the titanium-containing
granular powder (a) described in Example 1. The weight
compositional ratio of the metallic elements contained in the
honeycomb structure in terms of oxides was Ti02/W03/V205/GF=
89.8/4.73/0.50/5.00.
[0033]
Example 3
Titanium-containing Granular Powder (c) and Honeycomb
Catalyst for treating Exhaust Gas (C)
(1) Titanium-containing Granular Powder (c)
Granular powder of a composite oxide (c' ) was obtained
in the same manner as in Example 1 except that the amount of
ammonium paratungstate added in the preparation of the
granular powder of a composite oxide (af ) obtained in Example
1 was changed to 0.281 kg.
Titanium-containing granular powder (c) was prepared in
the same manner as in Example 1 except that the amount of
ammonium paratungstate added as the additive to the granular
powder of a composite oxide (cf) was changed to 1.13 kg.
Thevalue Awas obtainedbydividingthemass of titanium
atoms, which were a metallic element constituting the
composite oxide, contained in the titanium-containing
granular powder (c) by the atomicweight thereof, andthevalue
B was obtained by dividing the mass of nitrogen atoms, which
were an element constituting the additive ( e , ammonium
paratungstate), by the atomic weight thereof. As a result,
the values A and B were 297 and 3.60, respectively, and the
ratio (B/A) was 1.21 x
The titanium-containing granular powder (c) was
subjected to X-ray diffractiometry as described above. As a
result, titanium oxide contained in the titanium-containing
granular powder had an anatase crystalline structure, and the
peak intensity ratio (p1/p0) was 0.96. The specific surface
area of the titanium-containing granular powder measured by
the method described above was 93 m2/g.
( 2 ) Honeycomb Catalyst for treating Exhaust Gas (C)
Ahoneycomb catalyst fortreatingexhaustgas (C) formed
of the honeycomb structure was prepared in the same manner as
in Example 1 except that the titanium-containing granular
powder (c) was used instead of the titanium-containing
granular powder (a) described in Example 1. The weight
compositional ratio ofthe metallic elements containedinthe
honeycomb structure in terms of oxides was Ti02/W03/V205/GF=
89.8/4.73/0.50/5.00.
[0034]
Example 4
Titanium-containing Granular Powder (d) and Honeycomb
Catalyst for treating Exhaust Gas (D)
(1) Titanium-containing Granular Powder (d)
Granular powder of a composite oxide (df ) was obtained
in the same manner as in Example 1 except that the amount of
themetatitanic acid slurry in the preparation ofthe granular
powder of a composite oxide (a') obtained in Example 1 was
changed to 22.5 kg in terms of titanium dioxide, and the amount
of ammonium paratungstate added therein was changed to 1.41
kg -
Titanium-containing granular powder (d) was prepared in
the same manner as in Example 1 except that the amount of
ammonium paratungstate added as the additive to the granular
powder of a composite oxide (d') was changed to 1.41 kg.
The value Awas obtainedbydividingthemass of titanium
atoms, which were a metallic element constituting the
composite oxide, contained in the titanium-containing
granular powder (d) by the atomic weight thereof, andthe value
B was obtained by dividing the mass of nitrogen atoms, which
were an element constituting the additive ( i f ammonium
paratungstate), by the atomic weight thereof. As a result,
the values A and B were 282 and 4.49, respectively, and the
ratio (B/A) was 1.60 x lo-*.
The titanium-containing granular powder (d) was
subjected to X-ray diffractiometry as described above. As a
result, titanium oxide contained in the titanium-containing
granular powder had an anatase crystalline structure, and the
peak intensity ratio (pl/pO) was 0.91. The specific surface
area of the titanium-containing granular powder measured by
the method described above was 88 m2/g.
(2) Honeycomb Catalyst for treating Exhaust Gas (D)
A honeycomb catalyst for treating exhaust gas (D) formed
of the honeycomb structure was prepared in the same manner as
in Example 1 except that the titanium-containing granular
powder (d) was used instead of the titanium-containing
granular powder (a) described in Example 1. The weight
compositional ratio ofthe metallic elements containedinthe
honeycomb structure in terms of oxides was Ti02/W03/V205/GF=
85.1/9.45/0.50/5.00.
[0035]
Example 5
Titanium-containing Granular Powder (e) and Honeycomb
Catalyst for treating Exhaust Gas (E)
(1) Titanium-containing Granular Powder (e)
Granular powder of a composite oxide (ef) was obtained
in the same manner as in Example 1 except that the amount of
themetatitanic acid slurry in the preparation ofthe granular
powder of a composite oxide (af) obtained in Example 1 was
changedto 20.0 kginterms oftitaniumdioxide, and the amount
of ammonium paratungstate added therein was changed to 2.81
kg
Titanium-containing granular powder (e) was prepared in
the same manner as in Example 1 except that the amount of
ammonium paratungstate added as the additive to the granular
powder of a composite oxide (el) was changed to 2.81 kg.
The value Awas obtainedbydividingthemass of titanium
atoms, which were a metallic element constituting the
composite oxide, contained in the titanium-containing
granular powder (e) by the atomic weight thereof, andthe value
B was obtained by dividing the mass of nitrogen atoms, which
were an element constituting the additive ( e . ammonium
paratungstate), by the atomic weight thereof. As a result,
the values A and B were 250 and 8.99, respectively, and the
ratio (B/A) was 3.59 x
The titanium-containing granular powder (e) was
subjectedto X-ray diffractiometry as described above. As a
result, titanium oxide contained in the titanium-containing
granular powder had an anatase crystalline structure, and the
peak intensity ratio (p1/p0) was 0.83. The specific surface
area of the titanium-containing granular powder measured by
the method described above was 76 m2/g.
(2) Honeycomb Catalyst for treating Exhaust Gas (E)
Ahoneycombcatalystfortreatingexhaustgas (E) formed
of the honeycomb structure was prepared in the same manner as
in Example 1 except that the titanium-containing granular
powder (e) was used instead of the titanium-containing
granular powder (a) described in Example 1. The weight
compositional ratio ofthe metallic elements contained in the
honeycomb structure in terms of oxides was T~o~/wO~/V~O=~ /GF
75.6/18.9/0.50/5.00.
[0036]
Example 6
Titanium-containing Granular Powder (f) and Honeycomb
Catalyst for treating Exhaust Gas (F)
(1) Titanium-containing Granular Powder (f)
Titanium-containinggranularpowder (f) was obtainedin
the same manner as in Example 1 except that the additive added
to the granular powder of a composite oxide (af) obtained in
Example 1 was changed to tungsten disulfide (addition amount:
0.267 kg) .
Thevalue Awas obtainedbydividingthemass of titanium
atoms, which were a metallic element constituting the
composite oxide, contained in the titanium-containing
granular powder (f) by the atomicweight thereof, and the value
C was obtained by dividing the mass of nitrogen atoms, which
were an element constituting the additive ( i e , tungsten
disulfide), by the atomic weight thereof. As a result, the
values A and C were 297 and 2.16, respectively, and the ratio
(C/A) was 7.26 x
The titanium-containing granular powder (f) was
subjected to X-ray diffractiometry as described above. As a
result, titanium oxide contained in the titanium-containing
granular powder had an anatase crystalline structure, and the
peak intensity ratio (p1/p0) was 0.95. The specific surface
area of the titanium-containing granular powder measured by
the method described above was 94 m2/g.
(2) Honeycomb Catalyst for treating Exhaust Gas (F)
Ahoneycomb catalyst fortreatingexhaustgas (I?) formed
of the honeycomb structure was prepared in the same manner as
in Example 1 except that the titanium-containing granular
powder (f) was used instead of the titanium-containing
granular powder (a) described in Example 1. The weight
compositional ratio ofthe metallic elements containedinthe
honeycomb structure in terms of oxides was Ti02/W03/V205/GF=
89.8/4.73/0.50/5.00.
[0037]
Example 7
Titanium-containing Granular Powder (g) and Honeycomb
Catalyst for treating Exhaust Gas (G)
(1) Titanium-containing Granular Powder (g)
Titanium-containing granular powder (g) was obtainedin
the same manner as in Example 1 except that the additive added
to the granular powder of a composite oxide (br) obtained in
Example 2 was changedto tungsten disu1fi.de (addition amount:
0.535 kg). The value A was obtained by dividing the mass of
titaniumatoms, which were ametallic elementconstitutingthe
composite oxide, contained in the titanium-containing
granularpowder (g) by the atomicweight thereof, andthevalue
C was obtained by dividing the mass of nitrogen atoms, which
were an element constituting the additive ( e . , tungsten
disulfide), by the atomic weight thereof. As a result, the
values A and C were 297 and 4.31, respectively, and the ratio
(C/A) was 1.45 x
The titanium-containing granular powder (g) was
subjected to X-ray diffractiometry as described above. As a
result, titanium oxide contained in the titanium-containing
granular powder had an anatase crystalline structure, and the
peak intensity ratio (pl/pO) was 0.95. The specific surface
area of the titanium-containing granular powder measured by
the method described above was 94 m2/g.
(2) Honeycomb Catalyst for treating Exhaust Gas (G)
Ahoneycomb catalyst for treating exhaust gas (G) formed
of the honeycomb structure was prepared in the same manner as
in Example 1 except that the titanium-containing granular
powder (g) was used instead of the titanium-containing
granular powder (a) described in Example 1. The weight
compositional ratio ofthe metallic elements contained in the
honeycomb structure in terms of oxides was Ti02/W03/V205/GF =
89.8/4.73/0.50/5.00.
LO0381
Example 8
Titanium-containing Granular Powder (h) and ~oneycomb
Catalyst for treating Exhaust Gas (H)
(1) Titanium-containing Granular Powder (h)
Titanium-containing granular powder (h) was obtainedin
the same manner as in Example 1 except that the additive added
to the granular powder of a composite oxide (c') obtained in
Example 3 was changed to tungsten disulfide (addition amount:
1.07 kg). The value A was obtained by dividing the mass of
titaniumatoms, which were ametallic element constitutingthe
composite oxide, contained in the titanium-containing
granularpowder (h) by the atomicweight thereof, andthevalue
C was obtained by dividing the mass of nitrogen atoms, which
were an element constituting the additive ( e . tungsten
disulfide), by the atomic weight thereof. As a result, the
values A and C were 297 and 8.63, respectively, and the ratio
(C/A) was 2.90 x lo-*.
The titanium-containing granular powder (h) was
subjected to X-ray diffractiometry as described above. As a
result, titanium oxide contained in the titanium-containing
granular powder had an anatase crystalline structure, and the
peak intensity ratio (pl/pO) was 0.97. The specific surface
area of the titanium-containing granular powder measured by
the method described above was 94 m2/g.
(2) Honeycomb Catalyst for treating Exhaust Gas (H)
A honeycomb catalyst for treating exhaust gas (H) formed
of the honeycomb structure was prepared in the same manner as
in Example 1 except that the titanium-containing granular
powder (h) was used instead of the titanium-containing
granular powder (a) described in Example 1. The weight
compositional ratio ofthe metallic elements containedinthe
honeycomb structure in terms of oxides was T~O~/WO~/V~O=~ /GF
89.8/4.73/0.50/5.00.
[0039]
Example 9
Titanium-containing Granular Powder (i) and Honeycomb
Catalyst for treating Exhaust Gas (I)
(1) Titanium-containing Granular Powder (i)
Titanium-containing granular powder (i) was obtained in
the same manner as in Example 1 except that the additive added
to the granular powder of a composite oxide (a') obtained in
Example 1 was changed to tungsten hexachloride (addition
amount: 0.43 kg). The value A was obtained by dividing the
mass of titanium atoms, which were a metallic element
constituting the composite oxide, contained in the
titanium-containing granular powder (i) by the atomic weight
thereof, and the value D was obtained by dividing the mass of
nitrogen atoms, which were an element constituting the
additive (i. e., tungsten hexachloride) , by the atomic weight
thereof. As a result, the values A and D were 297 and 6-47,
respectively, and the ratio (D/A) was 2.18 x lo-'.
The titanium-containing granular powder (i) was
subjected to X-ray diffractiometry as described above. As a
result, titanium oxide contained in the titanium-containing
granular powder had an anatase crystalline structure, and the
peak intensity ratio (pl/pO) was 0.97. The specific surface
area of the titanium-containing granular powder measured by
the method described above was 91 m2/g.
(2) Honeycomb Catalyst for treating Exhaust Gas (I)
Ahoneycombcatalyst for treating exhaust gas (I) formed
of the honeycomb structure was prepared in the same manner as
in Example 1 except that the titanium-containing granular
powder (i) was used instead of the titanium-containing
granular powder (a) described in Example 1. The weight
compositional ratio ofthe metallic elements containedinthe
honeycomb structure in terms of oxides was TiO2/WO3/V2O5/G=~
89.8/4.73/0.50/5.00.
[0040]
Example 10
Titanium-containing Granular Powder (j) and Honeycomb
Catalyst for treating Exhaust Gas (J)
(1) Titanium-containing Granular Powder (j)
Titanium-containing granular powder ( j ) was obtainedin
the same manner as in Example 1 except that the additive added
to the granular powder of a composite oxide (b') obtained in
Example 2 was changed to tungsten hexachloride (addition
amount: 0.86 kg). The value A was obtained by dividing the
mass of titanium atoms, which were a metallic element
constituting the composite oxide, contained in the
titanium-containing granular powder (j) by the atomic weight
thereof, and the value D was obtained by dividing the mass of
nitrogen atoms, which were an element constituting the
additive (i.e., tungsten hexachloride), by the atomic weight
thereof. As a result, the values A and D were 297 and 12.9,
respectively, and the ratio (D/A) was 4.35 x
The titanium-containing granular powder (j) was
subjected to X-ray diffractiometry as described above. As a
result, titanium oxide contained in the titanium-containing
granular powder had an anatase crystalline structure, and the
peak intensity ratio (pl/pO) was 0.96. The specific surface
area of the titanium-containing granular powder measured by
the method described above was 92 rn2/g.
(2) Honeycomb Catalyst for treating Exhaust Gas (J)
Ahoneycomb catalyst fortreatingexhaustgas (J) formed
of the honeycomb structure was prepared in the same manner as
in Example 1 except that the titanium-containing granular
powder (j) was used instead of the titanium-containing
granular powder (a) described in Example 1. The weight
compositional ratio ofthe metallic elements containedinthe
honeycomb structure in terms of oxides was T~O~/WO~/V~OF,=/ GF
89.8/4.73/0.50/5.00.
[0041]
Example 11
Titanium-containing Granular Powder (k) and ~oneycomb
Catalyst for treating Exhaust Gas (K)
(1) Titanium-containing Granular Powder (k)
Titanium-containinggranularpowder (k) was obtained in
the same manner as in Example 1 except that the additive added
to the granular powder of a composite oxide (c') obtained in
Example 3 was changed to tungsten hexachloride (addition
amount: 1.71 kg). The value A was obtained by dividing the
mass of titanium atoms, which were a metallic element
constituting the composite oxide, contained in the
titanium-containing granular powder (k) by the atomic weight
thereof, and the value D was obtained by dividing the mass of
nitrogen atoms, which were an element constituting the
additive (i.e., tungsten hexachloride), by the atomic weight
thereof. As a result, the values A and D were 297 and 25.9,
respectively, and the ratio (D/A) was 8.71 x
The titanium-containing granular powder (k) was
subjected to X-ray diffractiometry as described above. As a
result, titanium oxide contained in the titanium-containing
granular powder had an anatase crystalline structure, and the
peak intensity ratio (pl/pO) was 0.95. The specific surface
area of the titanium-containing granular powder measured by
the method described above was 94 m2/g.
(2) Honeycomb Catalyst for treating Exhaust Gas (K)
A honeycomb catalyst for treating exhaust gas (K) formed
of the honeycomb structure was prepared in the same manner as
in Example 1 except that the titanium-containing granular
powder (k) was used instead of the titanium-containing
granular powder (a) described in Example 1. The weight
compositional ratio ofthe metallic elements containedinthe
honeycomb structure in terms of oxides was Ti02/W03/V205/GF =
89.8/4.73/0.50/5.00.
[0042]
Example 12
Titanium-containing Granular Powder (1) and Honeycomb
Catalyst for treating Exhaust Gas (L)
(1) Titanium-containing Granular Powder (1)
Titanium-containing granular powder (1) was obtainedin
the same manner as in Example 1 except that the additive added
to the granular powder of a composite oxide (b') obtained in
Example 2 was changed to ammonium molybdate (addition amount:
0.613 kg) . The value A was obtained by dividing the mass of
titaniumatoms, whichwere ametallicelementconstitutingthe
composite oxide, contained in the titanium-containing
granularpowder (1) by the atomicweight thereof, andthevalue
B was obtained by dividing the mass of nitrogen atoms, which
were an element constituting the additive ( e , ammonium
molybdate), by the atomic weight thereof. As a result, the
values A and B were 297 and 2.98, respectively, and the ratio
(B/A) was 1.00 x
The titanium-containing granular powder (1) was
subjected to X-ray diffractiometry as described above. As a
result, titanium oxide contained in the titanium-containing
granular powder had an anatase crystalline structure, and the
peak intensity ratio (pl/pO) was 0.98. The specific surface
area of the titanium-containing granular powder measured by
the method described above was 93 mZ/g.
(2) Honeycomb Catalyst for treating Exhaust Gas (L)
Ahoneycomb catalyst fortreatingexhaustgas (L) formed
of the honeycomb structure was prepared in the same manner as
in Example 1 except that the titanium-containing granular
powder (1) was used instead of the titanium-containing
granular powder (a) described in Example 1. The weight
compositional ratio ofthe metallic elements containedinthe
honeycomb structure in terms of oxides was Ti02/W03/Mo03/V205/GF
= 89.8/2.84/1.89/0.500/5.00.
[0043]
Example 13
~itanium-containing Granular Powder (m) and Honeycomb
Catalyst for treating Exhaust Gas (M)
(1) Titanium-containing Granular Powder (m)
Titanium-containing granular powder (m) was obtained in
the same manner as in Example 1 except that the additive added
to the granular powder of a composite oxide (b') obtained in
Example 2 was changed to molybdenum disulfide (addition
amount: 0.562 kg) . The value A was obtained by dividing the
mass of titanium atoms, which were a metallic element
constituting the composite oxide, contained in the
titanium-containing granular powder (m) by the atomic weight
thereof, and the value C was obtained by dividing the mass of
nitrogen atoms, which were an element constituting the
additive (i.e., molybdenum disulfide), by the atomic weight
thereof. As a result, the values A and C were 297 and 6.95,
respectively, and the ratio (C/A) was 2.34 x
The titanium-containing granular powder (m) was
subjected to X-ray diffractiometry as described above. As a
result, titanium oxide contained in the titanium-containing
granular powder had an anatase crystalline structure, and the
peak intensity ratio (p1/p0) was 0.97. The specific surface
area of the titanium-containing granular powder measured by
the method described above was 92 m2/g.
(2) Honeycomb Catalyst for treating Exhaust Gas (M)
A honeycomb catalyst for treating exhaust gas (M) formed
of the honeycomb structure was prepared in the same manner as
in Example 1 except that the titanium-containing granular
powder (m) was used instead of the titanium-containing
granular powder (a) described in Example 1. The weight
compositional ratio ofthemetallic elements contained in the
honeycomb structure in terms of oxides was T~O~/WO~/MOO~/V~O~/GF
= 89.8/2.84/1.89/0.500/5.00.
[0044]
Example 14
Titanium-containing Granular Powder (n) and Honeycomb
Catalyst for treating Exhaust Gas (N)
(1) Titanium-containing Granular Powder (n)
Titanium-containinggranularpowder (n) was obtainedin
the same manner as in Example 1 except that the additive added
to the granular powder of a composite oxide (b') obtained in
Example 2 was changed to molybdenum pentachloride (addition
amount: 0.951 kg) . The value A was obtained by dividing the
mass of titanium atoms, which were a metallic element
constituting the composite oxide, contained in the
titanium-containing granular powder (n) by the atomic weight
thereof, and the value D was obtained by dividing the mass of
nitrogen atoms, which were an element constituting the
additive e molybdenum pentachloride), by the atomic
weight thereof. As a result, the values A and D were 297 and
17.4, respectively, and the ratio (D/A) was 5.84 x
The titanium-containing granular powder (n) was
subjected to X-ray diffractiometry as described above. As a
result, titanium oxide contained in the titanium-containing
granular powder had an anatase crystalline structure, and the
peak intensity ratio (pl/pO) was 0.98. The specific surface
area of the titanium-containing granular powder measured by
the method described above was 92 m2/g.
(2) Honeycomb Catalyst for treating Exhaust Gas (N)
Ahoneycomb catalyst for treating exhaust gas (N) formed
of the honeycomb structure was prepared in the same manner as
in Example 1 except that the titanium-containing granular
powder (n) was used instead of the titanium-containing
granular powder (a) described in Example 1. The weight
compositional ratio of the metallic elements containedinthe
honeycomb structure in terms of oxides was Ti02/W03/Mo03/V205/GF
= 89.8/2.84/1.89/0.500/5.00.
[0045]
Example 15
Titanium-containing Granular Powder (0) and Honeycomb
Catalyst for treating Exhaust Gas (0)
(1) Titanium-containing Granular Powder (0)
Titanium-containing granular powder (0) was obtainedin
the same manner as in Example 1 except that the additive added
to the granular powder of a composite oxide (d') obtained in
Example 4 was changed to ammonium molybdate (addition amount:
1.53 kg). The value A was obtained by dividing the mass of
titaniumatoms, whichwere ametallic elementconstitutingthe
composite oxide, contained in the titanium-containing
granular powder (0) by the atomic weight thereof, andthe value
B was obtained by dividing the mass of nitrogen atoms, which
were an element constituting the additive ( e ammonium
molybdate), by the atomic weight thereof. As a result, the
values A and B were 282 and 7.45, respectively, and the ratio
(B/A) was 2.64 x lo-*.
The titanium-containing granular powder (0) was
subjected to X-ray diffractiometry as described above. As a
result, titanium oxide contained in the titanium-containing
granular powder had an anatase crystalline structure, and the
peak intensity ratio (pl/pO) was 0.90. The specific surface
area of the titanium-containing granular powder measured by
the method described above was 85 m2/g.
(2) Honeycomb Catalyst for treating Exhaust Gas (0)
Ahoneycombcatalyst fortreatingexhaustgas (0) formed
of the honeycomb structure was prepared in the same manner as
in Example 1 except that the titanium-containing granular
powder (0) was used instead of the titanium-containing
granular powder (a) described in Example 1. The weight
compositional ratio ofthemetallic elements containedinthe
honeycomb structure in terms of oxides was Ti02/W03/Mo03/V205/GF
= 8 5 . 1 / 4 . 7 3 / 4 . 7 3 / 0 . 5 0 0 / 5 . 0 0 .
[0046]
Example 16
Titanium-containing Granular Powder (p) and Honeycomb
Catalyst for treating Exhaust Gas (P)
(1) Titanium-containing Granular Powder (p)
Titanium-containing granular powder (p) was obtainedin
the same manner as in Example 1 except that the additive added
to the granular powder of a composite oxide (el ) obtained in
Example 5 was changed to ammonium molybdate (addition amount:
3.07 kg). The value A was obtained by dividing the mass of
titaniumatoms, whichwere ametallicelementconstitutingthe
composite oxide, contained in the titanium-containing
granular powder (p) bythe atomicweight thereof, andthevalue
B was obtained by dividing the mass of nitrogen atoms, which
were an element constituting the additive ( i f ammonium
molybdate), by the atomic weight thereof. As a result, the
values A and B were 250 and 14.9, respectively, and the ratio
(B/A) was 5.95 x
The titanium-containing granular powder (p) was
subjected to X-ray diffractiometry as described above. As a
result, titanium oxide contained in the titanium-containing
granular powder had an anatase crystalline structure, and the
peak intensity ratio (pl/pO) was 0.83. The specific surface
area of the titanium-containing granular powder measured by
the method described above was 78 m2/g.
(2) Honeycomb Catalyst for treating Exhaust Gas (P)
Ahoneycomb catalyst for treating exhaust gas (P) formed
of the honeycomb structure was prepared in the same manner as
in Example 1 except that the titanium-containing granular
powder (p) was used instead of the titanium-containing
granular powder (a) described in Example 1. The weight
compositional ratio ofthe metallic elements containedinthe
honeycomb structure in terms of oxides was T~O~/WO~/MOO~/VZO~/GF
= 75.6/9.45/9.45/0.500/5.00.
Comparative Example 1
Granular Powder of Composite Oxide (q) and Honeycomb Catalyst
for treating Exhaust Gas (Q)
(1) Granular Powder of Composite Oxide (q)
Granular powder of a composite oxide (q) was obtained
in the same manner as in the granular powder of a composite
oxide (a' ) of Example 1 except that the amount of the
metatitanic acid slurry in the preparation of the granular
powder of a composite oxide (af) obtained in Example 1 was
changed to 23.6 kg in terms of titanium dioxide, and the amount
of ammonium paratungstate added therein was changed to 1.41
kg
The granular powder of a composite oxide (q) was
subjected to X-ray diffractiometry as described above. As a
result, titanium oxide contained in the granular powder of a
composite oxide had an anatase crystalline structure, and the
peak intensity ratio (pl/pO) was 0.97. The specific surface
area of the granular powder of a composite oxide measured by
the method described above was 92 m2/g.
(2) Honeycomb Catalyst for treating Exhaust Gas ( Q )
Ahoneycomb catalyst fortreatingexhaustgas (Q) formed
of the honeycomb structure was prepared in the same manner as
in Example 1 except that the granular powder of a composite
oxide (q) was usedinsteadofthetitanium-containinggranular
powder (a) described in Example 1. The weight compositional
ratio of the metallic elements contained in the honeycomb
structure in terms of oxides was T~o~/wO~/V~O~=/ GF
89.8/4.73/0.50/5.00.
[0047]
Comparative Example 2
Granular Powder of Titanium Dioxide andAmmonium Paratungstate
(r) and Honeycomb Catalyst for treating Exhaust Gas (R)
(1) Granular Powder of Titanium Dioxide and Ammonium
Paratungstate (r)
Granular powder of titanium dioxide (r') was prepared
in the same manner as in (a') of Example 1 except that ammonium
paratungstate was not added to the metatitanic acid slurry
(25.0 kg in terms of titanium dioxide) . 1.41 kg of ammonium
paratungstate was added to the granular powder of titanium
dioxide (r'), and they were mixed homogeneously to prepare
granular powder oftitaniumdioxide and ammoniumparatungstate
(r). The granular powder of titanium dioxide and ammonium
paratungstate thus prepared was pulverized with a ball mill
to provide granular powder of titanium dioxide and ammonium
paratungstate (r) containing the granular powder that had a
particle diameter of 45 pm or less in an amount of 99.9% by
weight or more based on the total amount thereof.
The value Awas obtainedbydividingthemass of titanium
atoms, which were a metallic element constituting the
composite oxide, contained in the granular powder of titanium
dioxide and ammonium paratungstate (r) by the atomic weight
thereof, and the value B was obtained by dividing the mass of
nitrogen atoms, which were an element constituting the
additive (i.e., ammoniurnparatungstate), by the atomic weight
thereof. As a result, the values A and B were 297 and 4.49,
respectively, and the ratio (B/A) was 1.51 x lo-*.
The granular powder of titanium dioxide and ammonium
paratungstate (r) was subjected to X-ray diffractiometry as
described above. As a result, titanium oxide contained in the
granularpowderoftitaniumdioxideandammoniumparatungstate
had an anatase crystalline structure, and the peak intensity
ratio (pl/pO) was 0.97. The specific surface area of the
granularpowderoftitaniumdioxideandammoniumparatungstate
measured by the method described above was 95 m2/g.
(2) Honeycomb Catalyst for treating Exhaust Gas (R)
A honeycomb catalyst for treating exhaust gas (R) formed
of the honeycomb structure was prepared in the same manner as
i n E x a m p l e 1 e x c e p t t h a t t h e g r a n u l a r p o w d e r o f t i t a n i u m d i o x i d e
and ammonium paratungstate (r) was used instead of the
titanium-containing granular powder (a) described in ~xample
1. The weight compositional ratio of the metallic elements
contained in the honeycomb structure in terms of oxides was
T~O~/WO~/V~O=~ 8/9G.F8/ 4.73/0.50/5.00.
[0048]
Comparative Example 3
Granular Powder of Composite Oxide (s) and Honeycomb Catalyst
for treating Exhaust Gas (S)
(1) Granular Powder of Composite Oxide (s)
Granular powder of a composite oxide (s) was obtained
in the same manner as in the granular powder of a composite
oxide (dl) of Example 4 except that the amount of ammonium
paratungstate addedinthe preparation ofthe granular powder
of a composite oxide (d') obtained in Example 4 was changed
to 2.81 kg.
The granular powder of a composite oxide (s) was
subjected to X-ray diffractiometry as described above. As a
result, titanium oxide contained in the granular powder of a
composite oxide had an anatase crystalline structure, and the
peak intensity ratio ($/PO) was 0.97. The specific surface
area of the titanium-containing granular powder measured by
the method described above was 92 m2/g.
(2) Honeycomb Catalyst for treating Exhaust Gas (S)
A honeycomb catalyst for treating exhaust gas (S) formed
of the honeycomb structure was prepared in the same manner as
in Example 1 except that the granular powder of a composite
oxide (s) was usedinsteadofthetitanium-containinggranular
powder (a) described in Example 1. The weight compositional
ratio of the metallic elements contained in the honeycomb
structure in terms of oxides was Ti02/W03/V205/GF =
Comparative Example 4
Granular Powder of TitaniumDioxideandAmmoniumParatungstate
(t) and Honeycomb Catalyst for treating Exhaust Gas (T)
(1) Granular Powder of Titanium Dioxide and Ammonium
Paratungstate (t)
Granular powder of titanium and ammoniumparatungstate
(t) was obtained in the same manner as in Comparative Example
2 except that ammonium paratungstate (2.18 kg) was mixed with
22.5 kg ofthe granular powder oftitaniumdioxide and ammonium
paratungstate (r) in Comparative Example 2.
The value Awas obtainedbydividingthemass of titanium
atoms, which were a metallic element constituting the
composite oxide, contained in the granular powder of titanium
and ammonium paratungstate (t) by the atomic weight thereof,
and the value B was obtained by dividing the mass of nitrogen
atoms, which were an element constituting the additive (i. e.,
ammonium paratungstate) , by the atomic weight thereof. As a
result, the values A and B were 282 and 8.99, respectively,
and the ratio (B/A) was 3.19 x lo-*.
The granular powder of titanium dioxide and ammonium
paratungstate (t) was subjected to X-ray diffractiometry as
described above. As a result, titanium oxide contained in the
granular powder oftitaniumdioxide andammoniumparatungstate
had an anatase crystalline structure, and the peak intensity
ratio (P'/P') was 0.92. The specific surface area of the
granular powder oftitaniumdioxide andammoniumparatungstate
measured by the method described above was 85 m2/g.
(2) Honeycomb Catalyst for treating Exhaust Gas (T)
Ahoneycomb catalyst for treating exhaust gas (T) formed
of the honeycomb structure was prepared in the same manner as
inExample1exceptthatthegranularpowderoftitaniumdioxide
and ammonium paratungstate (t) was used instead of the
titanium-containing granular powder (a) described in Example
1. The weight compositional ratio of the metallic elements
contained in the honeycomb structure in terms of oxides was
Ti02/W03/V205/GF = 85.1/9.45/0.50/5.00.
[0050]
Comparative Example 5
Granular Powder of Composite Oxide (u) and Honeycomb Catalyst
for treating Exhaust Gas (U)
(1) Granular Powder of Composite Oxide (u)
Granular powder of a composite oxide (u) was obtained
in the same manner as in the granular powder of a composite
oxide (e') of Example 5 except that the amount of ammonium
paratungstate added in the preparation ofthe granular powder
of a composite oxide (el) obtained in Example 5 was changed
to 5.63 kg.
The granular powder of a composite oxide (u) was
subjected to X-ray diffractiometry as described above. As a
result, titanium oxide contained in the granular powder of a
composite oxide had an anatase crystalline structure, and the
peak intensity ratio (pl/pO) was 0.86. The specific surface
area of the titanium-containing granular powder measured by
the method described above was 79 m2/g.
(2) Honeycomb Catalyst for treating Exhaust Gas (U)
Ahoneycomb catalyst fortreatingexhaustgas (U) formed
of the honeycomb structure was prepared in the same manner as
in Example 1 except that the granular powder of a composite
oxide (u) was usedinsteadofthetitanium-containinggranular
powder (a) described in Example 1. The weight compositional
ratio of the metallic elements contained in the honeycomb
structure in terms of oxides was TiO2/WO3/V2O5/GF =
75.6/18.9/0.50/5.00.
[0051]
Comparative Example 6
Granular Powder of Ti.taniumDioxi.de andAmmoniumParatungstate
(v) and Honeycomb Catalyst for treating Exhaust Gas (V)
(1) Granular Powder of Titanium Dioxide and Ammonium
Paratungstate (v)
Granular powder of titanium dioxide and ammonium
paratungstate (v) was obtained in the same manner as in
Comparative Example 2 exceptthatarnmoniumparatungstate (5.63
kg) was mixed with 20.0 kg of the granular powder of titanium
dioxide and arnmoniumparatungstate (r) in Comparative Example
2.
The value Awas obtainedbydividingthemass of titanium
atoms, which were a metallic element constituting the
composite oxide, contained in the granular powder of titanium
dioxide and ammonium paratungstate (v) by the atomic weight
thereof, and the value B was obtained by dividing the mass of
nitrogen atoms, which were an element constituting the
additive (i-e., arnmoniumparatungstate), by the atomic weight
thereof. As a result, the values A and B were 250 and 18.0,
respectively, and the ratio (B/A) was 7.18 x lo-*.
The granular powder of titanium dioxide and ammonium
paratungstate (v) was subjected to X-ray diffractiometry as
described above. As a result, titanium oxide contained in the
granularpowderoftitaniumdioxideandammoniumparatungstate
had an anatase crystalline structure, and the peak intensity
ratio (pl/pO) was 0.80. The specific surface area of the
granularpowderoftitaniumdioxideandammoniumparatungstate
measured by the method described above was 75 m2/g.
(2) Honeycomb Catalyst for treating Exhaust Gas (V)
Ahoneycomb catalyst fortreatingexhaustgas (V) formed
of the honeycomb structure was prepared in the same manner as
in Example 1 except that the granular powder of titanium and
ammonium paratungstate (v) was used instead of the
titanium-containing granular powder (a) described in ~xample
1. The weight compositional ratio of the metallic elements
contained in the honeycomb structure in terms of oxides was
Ti02/W03/V205/GF = 75.6/18.9/0.50/5.00.
[0052]
Comparative Example 7
Granular Powder of Composite Oxide (w) and Honeycomb Catalyst
for treating Exhaust Gas (W)
(1) Granular Powder of Composite Oxide (w)
Granular powder of a composite oxide (w) was obtained
in the same manner as in the granular powder of a composite
oxide (b' ) of Example 2 except that 0.61 kg of ammonium
molybdate was added simultaneously with ammonium
paratungstate in the preparation of the granular powder of a
composite oxide (bf) obtained in Example 2.
The granular powder of a composite oxide (w) was
subjected to X-ray diffractiometry as described above. As a
result, titanium oxide contained in the granular powder of a
composite oxide had an anatase crystalline structure, and the
peak intensity ratio (pl/pO) was 0.98. The specific surface
area of the titanium-containing granular powder measured by
the method described above was 94 m2/g.
(2) Honeycomb Catalyst for treating Exhaust Gas (W)
Ahoneycomb catalyst fortreatingexhaustgas (W) formed
of the honeycomb structure was prepared in the same manner as
in Example 1 except that the granular powder of a composite
oxide (w) was usedinsteadofthetitanium-containinggranular
powder (a) described in Example 1. The weight compositional
ratio of the metallic elements contained in the honeycomb
structure in terms of oxides was T~O~/WO~/MOO~/V~=O ~/GF
89.8/2.84/1.89/0.500/5.00.
lo0531
Comparative Example 8
Granular Powder of Composite Oxide (x) and Honeycomb Catalyst
for treating Exhaust Gas (X)
(1) Granular Powder of Composite Oxide (x)
Granular powder of a composite oxide (x) was obtained
in the same manner as in the granular powder of a composite
oxide (d' ) of Example 4 except that 1.53 kg of ammonium
molybdate was added simultaneously with ammonium
paratungstate in the preparation of the granular powder of a
composite oxide (df) obtained in Example 4.
The granular powder of a composite oxide (x) was
subjected to X-ray diffractiometry as described above. As a
result, titanium oxide contained in the granular powder of a
composite oxide had an anatase crystalline structure, and the
peak intensity ratio (pl/pO) was 0.95. The specific surface
area of the titanium-containing granular powder measured by
the method described above was 86 m2/g.
(2) Honeycomb Catalyst for treating Exhaust Gas (X)
Ahoneycomb catalyst fortreatingexhaustgas (X) formed
of the honeycomb structure was prepared in the same manner as
in Example 1 except that the granular powder of a composite
oxide (x) was usedinsteadofthetitanium-containinggranular
powder (a) described in Example 1. The weight compositional
ratio of the metallic elements contained in the honeycomb
structure in terms of oxides was T~o~/wo~/Moo~/v~O=~ /GF
89.8/2.84/1.89/0.500/5.00.
[0054]
Comparative Example 9
Granular Powder of Composite Oxide (y) and Honeycomb Catalyst
for treating Exhaust Gas (Y)
(1) Granular Powder of Composite Oxide (y)
Granular powder of a composite oxide (y) was obtained
in the same manner as in the granular powder of a composite
oxide (e' ) of Example 5 except that 3.07 kg of ammonium
molybdate was added simultaneously with ammonium
paratungstate in the preparation of the granular powder of a
composite oxide (e') obtained in Example 5.
The granular powder of a composite oxide (y) was
subjected to X-ray diffractiometry as described above. As a
result, titanium oxide contained in the granular powder of a
composite oxide had an anatase crystalline structure, and the
peak intensity ratio (p1/p0) was 0.87. The specific surface
area of the titanium-containing granular powder measured by
the method described above was 77 m2/g.
(2) Honeycomb Catalyst for treating Exhaust Gas (Y)
A honeycomb catalyst for treating exhaust gas (Y) formed
of the honeycomb structure was prepared in the same manner as
in Example 1 except that the granular powder of a composite
oxide (y) was usedinsteadofthetitanium-containing granular
powder (a) described in Example 1. The weight compositional
ratio of the metallic elements contained in the honeycomb
structure in terms of oxides was Ti02/W03/Mo03/V205/GF =
7 5 . 6 / 9 . 4 5 / 9 . 4 5 / 0 . 5 0 0 / 5 . 0 0 .
[0055]
Comparative Example 10
Titanium-containing Granular Powder (z) and Honeycomb
Catalyst for treating Exhaust Gas (Z)
(1) Titanium-containing Granular Powder ( 2 )
Granular powder of a composite oxide (2' ) was obtained
in the same manner as in Example 1 except that the amount of
themetatitanic acid slurry in the preparation ofthe granular
powder of a composite oxide (a') obtained in Example 1 was
changed to 15.0 kg in terms of titanium dioxide, and the amount
of ammonium paratungstate added therein was changed to 0.845
kg -
Titanium-containing granular powder (z) was prepared in
the same manner as in Example 1 except that the additive added
to the granular powder of a composite oxide ( z ' ) was changed
to 11.3 kg of ammonium molybdate.
Thevalue Awas obtainedbydividingthemass of titanium
atoms, which were a metallic element constituting the
composite oxide, contained in the titanium-containing
granularpowder (2) bythe atomicweight thereof, andthevalue
B was obtained by dividing the mass of nitrogen atoms, which
were an element constituting the additive ( e , ammonium
molybdate), by the atomic weight thereof. As a result, the
values A and B were 188 and 55.1, respectively, and the ratio
(B/A) was 2.93 x lo-'.
The granular powder of a composite oxide (2) was
subjected to X-ray diffractiometry as described above. As a
result, titanium oxide contained in the titanium-containing
granular powder had an anatase crystalline structure, and the
peak intensity ratio ( $ / P O ) was 0.75. The specific surface
area of the titanium-containing granular powder measured by
the method described above was 70 m2/g.
(2) Honeycomb Catalyst for treating Exhaust Gas (Z)
Ahoneycombcatalystfortreatingexhaustgas (Z) formed
of the honeycomb structure was prepared in the same manner as
in Example 1 except that the titanium-containing granular
powder (2) was used instead of the titanium-containing
granular powder (a) described in Example 1. The weight
compositional ratio ofthe metallic elements contained in the
honeycomb structure in terms of oxides was T~O~/WO~/MOO~/V~O~/GF
= 56.7/2.84/35.0/0.500/5.00.
[0056]
The values A to F of the titanium-containing granular
powder, the composite oxides, and the mixtures of titanium
powder and ammonium paratungstate (which are hereinafter
referred totally as titanium-containing granular powder,
etc.) (a) to (z) are shown in Table 1, and the specific surface
area (SA) and the peak intensity ratio (pl/pO) of the (101)
plane of the anatase crystal of the titanium-containing
granular powder, etc. (a) to (z) , and the specific surface area
(SA), the pore volume (PV) , the result of the moldability test,
the denitration rate, the abrasion rate, and the heat
resistance (the peak intensity ratio (pl'/pl) of the (101) plane
of the anatase crystal before and after the test) of the
honeycomb catalyst for treating exhaust gas (A) - (Z) are shown
in Table 2.
[Table 11

[0058]
According to the results shown in Table 2, the specific
surface areas (SA) of the composite oxides of titanium and
tungsten used as raw materials for the titanium-containing
granular powder (a) to (p) of Examples and the
titanium-containing granular powder, etc. (q) to (z) of
Comparative Examples are from 70 to 95 m2/g, all of which are
within the range of from 40 to 300 m2/g. The peak intensity
ratios (pl/pO) of the (101) plane of the anatase crystal of
the titanium-containing granular powder relative to the
standardpowder oftitaniumdioxide are in a range of from0.75
to 0.98, all of which are within the range of from 0.30 to 1.3.
Onpreparingthehoneycomb catalyst fortreatingexhaust
gas (A) to (P) of Examples 1 to 16 by using the
titanium-containing granular powder (a) to (p) as raw
materials, the first structure that suffers honeycomb damage
on extrusion molding is the tenth structure or later at the
earliest among 20 structures, and no honeycomb damage occurs
in Examples 2 to 5, 15 and 16. In Examples 1 to 3 where the
amount of ammonium paratungstate added is changed, Examples
4 and 5 and Examples 15 and 16 where the amounts of both the
titanium and the additive added are changed, Examples 6 to 8
where the amount of tungsten disulfide added is changed, and
Examples 9to11wheretheamountoftungstenhexachlorideadded
is changed, such a tendency is found that when the ratio B/A
(or C/A or D/A) is larger, honeycomb damage are much harder
to occur.
As for the denitration rate, the abrasion rate and the
heat resistance of the honeycomb catalysts for treating
exhaust gas, results that have no practical problem are
obtained. In these evaluation items, such a tendency is found
that when the ratio B/A (or C/A or D/A) is larger, the abrasion
resistanceisincreased, butthe heat resistance is decreased.
[0059]
On the other hand, the honeycomb catalysts for treating
exhaust gas of Comparative Examples 1, 3, 5 and 7 to 9 using
the composite oxides (q) , (s) , (u) and (w) to (y) having no
additive added thereto suffer honeycomb damage in the
honeycomb structures in the early stage, i.e., the fourth to
ninth structures. It is confirmedtherefromthatthe addition
of the additive, such as the tungsten compound and the
molybdenum compound, to the composite oxide shows the effect
of improving the moldability on extrusion molding.
The honeycomb catalysts for treating exhaust gas of
Comparative Examples 2, 4 and 6 using the mixtures containing
the sole titanium dioxide (r), (t) or (v) having the additive
(ammonium paratungstate) added thereto suffer no honeycomb
damage duringthe extrusionmolding test of 20 structures, and
thus are good in moldability on extrusion molding, but are
inferior in heat resistance to the other Examples and
Comparative Examples. It is understood therefrom that the
addition of the additive, such as the nitrogen compound, the
sulfur compound or the chlorine compound containing tungsten
or molybdenum, to the composite oxide containing tungsten or
molybdenumprovides a honeycomb catalyst for treating exhaust
gas that has good moldability on extrusion molding and high
heat resistance.
Comparative Example 10 where the value B/A is 6.34 x lo-',
which is far larger than the upper limit of the value B/A (2.78
x10-I) suffersnohoneycombdamageduringtheextrusionmolding
test of 20 structures, and thus are good in moldability on
extrusion molding, but provides the worst results in
denitration rate and heat resistance.
CLAIMS
[Claim 11
Titanium-containing granular powder for producing a
honeycomb catalyst for treating exhaust gas, comprising (X)
a composite oxide of metallic elements containing at least one
of tungsten and molybdenum, and titanium, and (Y) an additive
selected from (i) a tungsten-containing nitrogen compound,
(ii) a tungsten-containing sulfur compound, (iii) a
tungsten-containing chlorine compound, (iv) a
molybdenum-containing nitrogen compound, (v) a
molybdenum-containing sulfur compound and (vi) a
molybdenum-containing chlorine compound,
(1) in the case where the additive (Y) contains the
tungsten-containing nitrogen compound (i) or the
molybdenum-containing nitrogen compound (iv), a molar ratio
(B/A) being in a range of from 8.70 x to 2.78 x lo-', wherein
A represents a molar number of titanium atoms contained in the
titanium-containing granular powder, and B represents amolar
number of nitrogen atoms contained inthetitanium-containing
granular powder,
(2) in the case where the additive (Y) contains the
tungsten-containing sulfur compound (ii) or the
molybdenum-containing sulfur compound (v), amolarratio (C/A)
being in a range of from 6.96 x to 5.55 x lo-', wherein
A represents a molar number of titanium atoms contained in the
titanium-containing granular powder, and C represents amolar
number of sulfur atoms contained in the titanium-containing
granular powder, and
(3) in the case where the additive (Y) contains the
tungsten-containing chlorine compound (iii) or the
molybdenum-containing chlorine compound (vi), a molar ratio
(D/A) being in a range of from 6.96 x to 6.94 x lo-', wherein
A represents a molar number of titanium atoms contained in the
titanium-containing granular powder, and D represents amolar
number of chlorine atoms containedinthetitanium-containing
granular powder.
[Claim 21
The titanium-containing granular powder for producing
a honeycomb catalyst for treating exhaust gas according to
claiml, wherein onmeasuringthetitanium-containinggranular
powder by X-ray diffractiometry, titanium oxide contained in
the titanium-containing granular powder has an anatase
crystalline structure, a peak intensity ratio (pl/pO) is in
a range of from 0.30 to 1.3, wherein P' represents a peak
intensity of a (101) plane of the anatase crystal, and PO
represents a peak intensity of a (101) plane of an anatase
crystal of standard powder of titanium dioxide (MC-90,
produced by Ishihara Sangyo Kaisha, Ltd.), and
the titanium-containing granular powder has a specific
surface area in a range of from 40 to 300 m2/g.
[Claim 31
The titanium-containing granular powder for producing
a honeycomb catalyst for treating exhaust gas according to
claim 1, wherein the titanium-containing granular powder
contains the granular substance that has a particle diameter
of 45 pm or less in an amount of 99.9% by weight or more based
on the total amount thereof.
[Claim 41
The titanium-containing granular powder for producing
a honeycomb catalyst for treating exhaust gas according to
claiml, whereinthetungsten-containingnitrogen compound (i)
is at least one selectedfromammoniumparatungstate, ammonium
metatungstate, ammonium phosphotungstate and ammonium
tetrathiotungstate, and the molybdenum-containing nitrogen
compound (iv) is at least one selectedfromammoniummolybdate,
ammonium phosphomolybdate and ammonium tetrathiomolybdate.
[Claim 51
The titanium-containing granular powder for producing
a honeycomb catalyst for treating exhaust gas according to
claiml, wherein the tungsten-containing sulfur compound (ii)
is tungsten disulfide, and the molybdenum-containing sulfur
compound (v) is molybdenum disulfide.
[Claim 61
The titanium-containing granular powder for producing
a honeycomb catalyst for treating exhaust gas according to
claim 1, wherein the tungsten-containing chlorine compound
(iii) is tungsten hexachloride, andthemolybdenum-containing
chlorine compound (vi) is molybdenum pentachloride.
[Claim 71
A honeycomb catalyst for treating exhaust gas,
comprising the titanium-containing granular powder according
to claim 1 and an active ingredient, a content of the
titanium-containing granular powder being 60% by weight or
more.
[Claim 81
The honeycomb catalyst for treating exhaust gas
accordingto claim7, whereintheactive ingredient is vanadium
oxide.
[Claim 91
The honeycomb catalyst for treating exhaust gas
according to claim 7, wherein the honeycomb catalyst for
treating exhaust gas is a catalyst for removing nitrogen
oxides.
[Claim 101
A method for producing titanium-containing granular
powder for producing a honeycomb catalyst for treating exhaust
gas, comprising mixing (X) a composite oxide of metallic
elements containing at least one of tungsten and molybdenum,
and titanium, and (Y) an additive selected from (i) a
tungsten-containing nitrogen compound, (ii) a
tungsten-containing sulfur compound, (iii) a
tungsten-containing chlorine compound, (iv) a
molybdenum-containing nitrogen compound, (V a
molybdenum-containing sulfur compound and (vi) a
molybdenum-containing chlorine compound, in the following
ratio:
(1) in the case where the additive (Y) used is the
tungsten-containing nitrogen compound (i) or the
molybdenum-containing nitrogen compound (iv), the method
comprisingmixingthe composite oxide and the additive tomake
a molar ratio (B/A) in a range of from 8.70 x to 2.78 x
lo-', wherein A represents a molar number of titanium atoms
contained in the titanium-containing granular powder, and B
represents a molar number of nitrogen atoms contained in the
titanium-containing granular powder,
(2) in the case where the additive (Y) used is the
tungsten-containing sulfur compound (ii) or the
molybdenum-containing sulfur compound (v), the method
comprisingmixingthe composite oxide and the additive tomake
a molar ratio (C/A) in a range of from 6.96 x to 5.55 x
10-l~wh erein A represents a molar number of titanium atoms
contained in the titanium-containing granular powder, and C
represents a molar number of sulfur atoms contained in the
titanium-containing granular powder, and
(3) in the case where the additive (Y) used is the
tungsten-containing chlorine compound (iii) or the
molybdenum-containing chlorine compound (vi), the method
comprising mixing the composite oxide and the additive to make
a molar ratio (D/A) being in a range of from 6.96 x to 6.94
x lo-', wherein A represents a molar number of titanium atoms
contained in the titanium-containing granular powder, and D
represents a molar number of chlorine atoms contained in the
titanium-containing granular powder.
[Claim 111
The method for producing titanium-containing granular
powder forproducingahoneycomb catalyst fortreatingexhaust
gas according to claim 10, wherein the titanium-containing
granular powder is obtained by mixing the composite oxide (X)
of metallic elements and at least one of the additive (Y)
selected from (i) a tungsten-containing nitrogen compound,
(ii) a tungsten-containing sulfur compound, (iii) a
tungsten-containing chlorine compound, (iv) a
molybdenum-containing nitrogen compound, (v) a
molybdenum-containing sulfur compound and (vi) a
molybdenum-containing chlorine compound.
[Claim 121
Amethod forproducingahoneycomb catalyst for treating
exhaust gas, comprising
(1) mixing the titanium-containing granular powder for
producing a honeycomb c a t a l y s t f o r t r e a t i n g exhaust g a s
producedbytheproductionmethodaccordingto claim10, water,
and vanadium oxide or a p r e c u r s o r t h e r e o f t o prepare a s l u r r y
l i q u i d containing t h e s e i n g r e d i e n t s ,
( 2 ) kneading t h e s l u r r y l i q u i d and a s t r u c t u r a l
r e i n f o r c i n g m a t e r i a l t o prepare a mixture,
(3) extrusion-moldingthemixture toprepare ahoneycomb
s t r u c t u r e ,
( 4 ) drying t h e honeycomb s t r u c t u r e , and then baking t h e
honeycomb s t r u c t u r e under a t e m p e r a t u r e c o n d i t i o n o f from 400
t o 700°C.