w 1
DESCRIPTION
CATALYST FOR PRODUCING MONOCYCLIC AROMATIC HYDROCARBON
AND PRODUCTION METHOD OF MONOCYCLIC AROMATIC HYDROCARBON
5
TECHNICAL FIELD
[0001]
The present invention relates to a catalyst for producing monocyclic aromatic
hydrocarbon that is for producing monocyclic aromatic hydrocarbon from oil containing
10 a large amount of poly cyclic aromatic hydrocarbon and a production method of
monocyclic aromatic hydrocarbon.
Priority is claimed on Japanese Patent Application No. 2010-294185, filed
December 28, 2010, the content of which is incorporated herein by reference.
15 BACKGROUND ART
! [0002]
Light Cycle Oil (hereinafter, called "LCO") as cracked light oil that is generated
by a fluidized catalytic cracking contains a large amount of polycyclic aromatic
hydrocarbon and is used as light oil or heavy oil. However, in recent years,
20 investigations have been conducted to obtain, from LCO, monocyclic aromatic
|
hydrocarbons having 6 to 8 carbon numbers (for example, benzene, toluene, xylene,
j
ethylbenzene and the like), which can be utilized as high octane value gasoline base
materials or petrochemical feedstocks and have a high added value.
For example, Patent Documents 1 to 3 suggest methods for producing
25 monocyclic aromatic hydrocarbons from polycyclic aromatic hydrocarbons that are
^jj 2
contained in LCO and the like in a large amount, by using a zeolite catalyst.
However, Patent Documents 1 to 3 do not disclose that the yield of monocyclic
aromatic hydrocarbon having 6 to 8 carbon number produced by the method is
sufficiently high.
5 [0003]
When monocyclic aromatic hydrocarbon is produced from heavy crude oil
containing polycyclic aromatic hydrocarbon, catalyst regeneration for removing a
carbonaceous substance needs to be performed with a high frequency since a large
amount of carbonaceous substance is precipitated on the catalyst and rapidly decreases
10 the activity. Moreover, when a circulating fluidized bed for performing a process of
efficiently repeating reaction-catalyst regeneration is employed, the temperature for
catalyst regeneration needs to be higher than the reaction temperature, so the temperature
environment of the catalyst becomes more severe.
i
When a zeolite catalyst is used as a catalyst under such a severe condition,
15 hydrothermal deterioration of the catalyst continues, and the reaction activity decreases
over time. Accordingly, the improvement of hydrothermal stability is required for the
catalyst. However, for the zeolite catalyst disclosed in Patent Documents 1 to 3, a
measure for improving hydrothermal stability was not taken, and the practical usefulness
thereof was extremely low.
20 [0004]
As the method for improving hydrothermal stability, a method using zeolite
having a high Si/Al ratio, a method of stabilizing a catalyst by performing hydrothermal
treatment in advance, such as USY-type zeolite, a method of adding phosphorus to
zeolite, a method of adding a rare-earth metal to zeolite, a method of improving a
25 structure directing agent at the time of zeolite synthesis, and the like are known.
Among these, addition of phosphorus is known to have effects that improve not
only the hydrothermal stability but also the selectivity resulting from inhibiting the
precipitation of a carbonaceous substance during fluidized catalytic cracking, abrasion
resistance of a binder, and the like. Accordingly, phosphorus is frequently added to
5 catalysts for a catalytic cracking reaction.
The catalysts for catalytic cracking that are obtained by adding phosphorus to
zeolite are disclosed in, for example, Patent Documents 4 to 6.
That is, Patent Document 4 discloses a method of producing olefin from naphtha
by using a catalyst containing ZSM-5 to which phosphorus, gallium, germanium, and tin
10 has been added. Patent Document 4 aims to improve the selectivity in generating olefin
by inhibiting generation of methane or an aromatic fraction by method of adding
phosphorus, and to improve the yield of olefin by securing high activity with a short
contact time.
Patent Document 5 discloses a method of producing olefin from heavy
15 hydrocarbon with a high yield, by using a catalyst in which phosphorus is supported on
I ZSM-5 containing zirconium and a rear-earth metal and a catalyst which contains USY
zeolite, REY zeolite, kaolin, silica, and alumina.
Patent Document 6 discloses a method of producing ethylene and propylene
with a high yield, by converting hydrocarbon by using a catalyst containing ZSM-5
20 supporting phosphorus and a transition metal.
[0005]
As described above, addition of phosphorus to zeolite is disclosed in Patent
Documents 4 to 6. However, all of the methods mainly aimed to improve the yield of
olefin, and failed to produce monocyclic aromatic hydrocarbon having 6 to 8 carbon
25 number with a high yield. For example, Table 2 of Patent Document 6 discloses the
% 4
yield of olefin (ethylene and propylene) and BTX (benzene, toluene, and xylene). In the
table, while the yield of olefin is 40 mass%, the yield of BTX is as low as about 6
mass%.
Accordingly, a catalyst for producing monocyclic aromatic hydrocarbon that
5 makes it possible to produce monocyclic aromatic hydrocarbon having 6 to 8 carbon
number with a high yield from oil feedstock containing polycyclic aromatic hydrocarbon
and to prevent the reduction in the yield of the monocyclic aromatic hydrocarbon over
time has practically not been known.
10 Prior art documents
Patent documents
[0006]
[Patent Document 1] Japanese Unexamined Patent Application, First
Publication No. H3-2128
15 [Patent Document 2] Japanese Unexamined Patent Application, First
Publication No. H3-52993
[Patent Document 3] Japanese Unexamined Patent Application, First
Publication No. H3-26791
[Patent Document 4] Published Japanese Translation No. 2002-525380 of the
20 PCT International Publication
[Patent Document 5] Japanese Unexamined Patent Application, First
Publication No. 2007-190520
[Patent Document 6] Published Japanese Translation No. 2007-530266 of the
PCT International Publication
25
$ 5
DISCLOSURE OF INVENTION
Problems to be solved by the invention
[0007]
The present invention aims to provide a catalyst for producing monocyclic
5 aromatic hydrocarbon that makes it possible to produce monocyclic aromatic
hydrocarbon having 6 to 8 carbon number with a high yield from oil feedstock containing
polycyclic aromatic hydrocarbon and to prevent the reduction in the yield of the
monocyclic aromatic hydrocarbon having 6 to 8 carbon number caused over time, and a
production method of monocyclic aromatic hydrocarbon.
10
Means to solve the problems
[0008]
[1] A catalyst for producing aromatic hydrocarbon that is for producing
monocyclic aromatic hydrocarbon having 6 to 8 carbon number from oil feedstock
15 having a 10 volume% distillation temperature of 140°C or higher and a 90 volume%
distillation temperature of 380°C or lower, the catalyst includes crystalline
aluminosilicate and phosphorus, in which a molar ratio (P/Al ratio) between phosphorus
contained in the crystalline aluminosilicate and aluminum of the crystalline
aluminosilicate is from 0.1 to 1.0.
20 [2] The catalyst for producing monocyclic aromatic hydrocarbon according to
[1], in which the phosphorus content is 0.1 to 10 mass% based on the catalyst weight.
[3] The catalyst for producing monocyclic aromatic hydrocarbon according to
[1] or [2], in which the crystalline aluminosilicate is medium pore size zeolite.
j [4] The catalyst for producing monocyclic aromatic hydrocarbon according to
I 25 any one of [1] to [3], in which the crystalline aluminosilicate is MFI-type zeolite.
j
[5] A production method of monocyclic aromatic hydrocarbon having 6 to 8
carbon number, including bringing oil feedstock having a 10 volume% distillation
temperature of 140°C or higher and a 90 volume% distillation temperature of 380°C or
lower into contact with the catalyst for producing monocyclic aromatic hydrocarbon
5 according to any one of [1] to [4].
[6] The production method of monocyclic aromatic hydrocarbon having 6 to 8
carbon number according to [5], in which the oil feedstock includes light cycle oil
generated from a fluidized catalytic cracking.
[7] The production method of a monocyclic aromatic hydrocarbon having 6 to 8
10 carbon number according to [5] or [6], further including bringing the oil feedstock into
contact with the catalyst for producing monocyclic aromatic hydrocarbon by using a
fluidized-bed reaction equipment.
Effect of the invention
15 [0009]
According to the catalyst for producing monocyclic aromatic hydrocarbon and
the production method of monocyclic aromatic hydrocarbon having 6 to 8 carbon number
of the present invention, monocyclic aromatic hydrocarbon having 6 to 8 carbon number
may be produced with a high yield from oil feedstock containing polycyclic aromatic
20 hydrocarbon, and the reduction in the yield of the monocyclic aromatic hydrocarbon
having 6 to 8 carbon number over time may be prevented.
BEST MODE FOR CARRYING OUT THE INVENTION
[0010]
I 25 Hereinafter,, an embodiment of a catalyst for producing monocyclic aromatic
hydrocarbon and a production method of monocyclic aromatic hydrocarbon of the
present invention will be described.
[0011]
(Catalyst for producing monocyclic aromatic hydrocarbon)
.5 The catalyst for producing monocyclic aromatic hydrocarbon of the present
embodiment (hereinafter, abbreviated to a "catalyst") is for producing monocyclic
aromatic hydrocarbon having 6 to 8 carbon number (hereinafter, abbreviated to
"monocyclic aromatic hydrocarbon") from oil feedstock containing polycyclic aromatic
hydrocarbon and saturated hydrocarbon, and contains crystalline aluminosilicate and
10 phosphorus.
[0012]
[Crystalline aluminosilicate]
The crystalline aluminosilicate is not particularly limited, but is preferably,
pentasil type zeolite or medium pore size zeolite. As the medium pore size zeolite,
15 zeolites having an MFI, MEL, TON, MTT, MRE, FER, AEL, or EUO type crystal
structure are more preferable. Moreover, zeolites having an MFI and/or MEL type
crystal structure are particularly preferable since they further increase the yield of
monocyclic aromatic hydrocarbon.
The zeolites of MFI type, MEL type, and the like belong to zeolites having
20 known types of structures that are publicly introduced by The Structure Commission of
the International Zeolite Association (Atlas of Zeolite Structure Types, W. M. Meiyer and
D. H. Olson (1978), Distributed by Polycrystal Book Service, Pittsburgh, PA, USA).
Provided that the total amount of the catalyst (total weight of the catalyst) is 100
mass%, the content of the crystalline aluminosilicate in the catalyst is preferably 10 to 95
25 mass%, more preferably 20 to 80 mass%, and particularly preferably 25 to 70 mass%.
I
fe 8
When the content of the crystalline aluminosilicate is from 10 to 95 mass%, a sufficiently
high degree of catalytic activity is obtained.
[0013]
[Phosphorus]
5 A molar ratio (P/Al ratio) between phosphorus contained in the crystalline
aluminosilicate and aluminum contained in the crystalline aluminosilicate is from 0.1 to
1.0. When the P/Al ratio exceeds 1.0, the yield of monocyclic aromatic hydrocarbon
decreases. Accordingly, the P/Al ratio is 1.0 or lower, preferably 0.95 or lower, and
more preferably 0.9 or lower.
10 When the P/Al ratio is lower than 0.1, the yield of monocyclic aromatic
hydrocarbon in a static state decreases. Accordingly, the P/Al ratio is 0.1 or higher,
preferably 0.15 or higher, and even more preferably 0.2 or higher.
[0014]
Provided that the total mass of the crystalline aluminosilicate is 100 mass%, the
15 content of phosphorus contained in the crystalline aluminosilicate in the catalyst of the
present embodiment is preferably 0.1 to 3.5 mass%. Moreover, the lower limit of the
content is more preferably 0.2 mass% or more, and the upper limit thereof is more
preferably 3.0 mass% or less and particularly preferably 2.8 mass% or less. When the
content of phosphorus supported on the crystalline aluminosilicate is 0.1 mass% or more,
20 the reduction in the yield of monocyclic aromatic hydrocarbon caused over time can be
prevented, and when it is 3.5 mass% or less, the yield of monocyclic aromatic
hydrocarbon can be increased.
In addition, the upper limit of the content of phosphorus in the catalyst of the
present embodiment is far lower than the upper limit of the content of phosphorus in the
25 catalyst disclosed in Patent Documents 4 to 6. It is considered that this is because the
i
^ 9
oil feedstock of the reaction to which the catalyst of the present embodiment is applied
contains a large amount of polycyclic aromatic hydrocarbon and exhibits low reactivity.
In the present embodiment, when the amount of phosphorus added is too large, this
makes it more difficult for the oil feedstock to react, and a degree of aromatization
5 activity is lowered. Accordingly, the yield of monocyclic aromatic hydrocarbon is
reduced. On the other hand, the oil feedstock in Patent Documents 4 to 6 (for example,
vacuum gas oil or the like that is used as oil feedstock of a fluidized catalytic cracking) is
heavy, has a large molecular weight, and is easily adsorbed onto a catalyst.
Consequently, this oil is more easily cracked than a fraction of LCO or the like.
10 Furthermore, because this oil is easily cracked into light olefin, a big problem does not
arise even if a large amount of phosphorus is supported, and a degree of aromatization
activity is lowered.
[0015]
The method of adding phosphorus to the catalyst of the present embodiment is
15 not particularly limited, and examples thereof include a method of causing phosphorus to
be supported on crystalline aluminosilicate by ion exchange, impregnation, or the like, a
method of replacing a portion of the inside of the crystalline aluminosilicate skeleton
with phosphorus by adding a phosphorus compound during zeolite synthesis, a method of
using phosphorus-containing crystallization accelerator during zeolite synthesis, or the
20 like. An aqueous phosphate ion-containing solution used at this time is not particularly
limited, and it is possible to preferably use solutions that are prepared by dissolving
phosphoric acid, diammonium hydrogen phosphate, ammonium dihydrogen phosphate,
other water-soluble phosphoric acid salts, or the like in water at any concentration.
[0016]
25 The catalyst of the present embodiment is obtained by baking (baking
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temperature of 300 to 900°C) the above phosphorus-containing crystalline
aluminosilicate.
[0017]
[Shape]
5 The catalyst of the present embodiment is shaped into, for example, powder,
granules, pellets, or the like, according to the reaction mode.
For example, the catalyst is shaped into powder in the case of a fluidized bed
and shaped into granules or pellets in the case of a fixed bed. An average particle size
of the catalyst used in a fluidized bed is preferably 30 to 180 urn, and more preferably 50
10 to 100 urn. Moreover, a bulk density of the catalyst used in a fluidized bed is preferably
0.4 to 1.8 g/cc, and more preferably 0.5 to 1.0 g/cc.
The average particle size indicates a size of particles accounting for 50 mass% in
a particle size distribution obtained by classification performed by sieving, and the bulk
density is a value measured by the method of JIS standard R9301-2-3.
15 In order to obtain a catalyst having a granule or pellet shape, an inactive oxide as
a binder or the like may be optionally mixed in crystalline aluminosilicate or a catalyst,
and then the resultant may be molded using various molding machines. Examples of
the inactive oxide include silica, alumina, zirconia, titania, a mixture of these, or the like.
[0018]
20 When the catalyst of the present embodiment contains an inorganic oxide such
as a binder, those containing phosphorus as a binder may be used. Examples of the
inorganic oxide such as a binder include silica, alumina, zirconia, titania, a mixture of
these, and the like. When the catalyst contains the inorganic oxide such as a binder, the
amount of binder is preferably 10 to 80 mass%, and more preferably 25 to 75 mass%,
25 based on the total weight of the catalyst.
% 11
Moreover, when the catalyst contains an inorganic catalyst such as a binder, the
catalyst may be produced by mixing the binder or the like with crystalline
aluminosilicate and then adding phorphorus thereto.
When the catalyst contains the inorganic oxide such as a binder, the content of
5 phosphorus is preferably 0.1 to 10 mass%, based on the total weight of the catalyst. In
addition, the lower limit of the content is preferably 0.5 mass% or more, and the upper
limit thereof is preferably 9 mass% or less and particularly preferably 8 mass% or less.
When the content of phosphorus based on the total weight of the catalyst is 0.1 mass% or
more, the reduction in the yield of monocyclic aromatic hydrocarbon caused over time
10 can be prevented, and when it is 10 mass% or less, the yield of monocyclic aromatic
hydrocarbon can be increased.
[0019]
(Production method of monocyclic aromatic hydrocarbon)
The production method of monocyclic aromatic hydrocarbon of the present
15 embodiment is a method of bringing oil feedstock into contact with the catalyst to cause
a reaction.
The reaction is a method in which the oil feedstock is caused to come into
I contact with an acid point of the catalyst to cause various reactions such as cracking,
dehydrogenation, cyclization, and hydrogen transfer, whereby polycyclic aromatic
20 hydrocarbon undergoes ring opening and is converted into monocyclic aromatic
hydrocarbon.
[0020]
[Oil feedstock]
•
The oil feedstock used in the present embodiment is oil having a 10 volume%
I
! 25 distillation temperature of 140°C or higher and a 90 volume% distillation temperature of
1!
^ 12
380°C or lower. When oil having a 10 volume% distillation temperature of lower than
140°C is used, BTX is produced from light oil, and this does not fit for the main object of
the present embodiment. Accordingly, the 10 volume% distillation temperature of the
oil is preferably 140°C or higher, and more preferably 150°C or higher. Moreover,
5 when oil feedstock having a 90 volume% distillation temperature of higher than 380°C is
used, the amount of coke deposited onto the catalyst increases, whereby the catalytic
activity tends to be rapidly reduced. Accordingly, the 90 volume% distillation
temperature of the oil feedstock is preferably 380°C or lower, and more preferably 360°C
or lower.
10 In addition, the 10 volume% distillation temperature, 90 volume% distillation
temperature, and endpoint described herein are values measured based on JIS K2254
"Petroleum products-Determination of distillation characteristics".
Examples of the oil feedstock having a 10 volume% distillation temperature of
140°C or higher and a 90 volume% distillation temperature of 380°C or lower include
15 Light Cycle Oil (LCO) generated by a fluidized catalytic cracking, coal-liquefied oil,
hydrocracked and refined heavy oil, straight-run kerosene, straight-run light oil, coker
kerosene, coker light oil, hydrocracked and refined sand oil, and the like. Among these,
Light Cycle Oil (LCO) generated by a fluidized catalytic cracking is preferably included
in the oil feedstock.
20 When the oil feedstock contains a large amount of polycyclic aromatic
hydrocarbon, the yield of monocyclic aromatic hydrocarbon having 6 to 8 carbon number
decreases. Accordingly, the content of polycyclic aromatic hydrocarbon (polycyclic
aromatic fraction) in the oil feedstock is preferably 50 volume% or less, and more
preferably 30 volume% or less.
CJ 13
In addition, the polycyclic aromatic fraction described herein refers to the sum
of the content of bicyclic aromatic hydrocarbon (bicyclic aromatic fraction) and the
content of aromatic hydrocarbon having three or more rings (aromatic fraction having
three or more rings) that are measured based on JPI-5S-49 "Petroleum
5 products-Determination of hydrocarbon types-High performance liquid
chromatography".
[0021]
[Reaction mode]
As the reaction mode at the time when the oil feedstock is brought into contact
10 with the catalyst and reacted, a fixed bed, a moving bed, a fluidized bed, or the like can
be used. In the present embodiment, a heavy fraction is used as oil feedstock.
Accordingly, a fluidized bed that makes it possible to continuously remove the coke
component attached to the catalyst and to stably carry out the reaction is preferable.
Particularly, a continuously regenerative type fluidized bed in which a catalyst is
15 circulated between a reactor and a regenerator so that reaction-regeneration can be
! continuously repeated, is particularly preferred. It is preferable that the oil feedstock to
; be brought into contact with the catalyst be in a gaseous state.
i
Moreover, the oil feedstock may be optionally diluted with gas, and when
unreacted oil is generated, this may be optionally recycled.
20 [0022]
[Reaction temperature]
The reaction temperature at the time when the oil feedstock is brought into
contact with the catalyst and reacted is not particularly limited, but is preferably 350 to
700°C. The lower limit of the temperature is more preferably 450°C or higher since
25 sufficient reaction activity is obtained. On the other hand, the upper limit thereof is
# 14
more preferably 650°C or lower since this temperature is advantageous in view of energy
and makes it possible to easily regenerate the catalyst.
[0023]
[Reaction pressure]
5 The reaction pressure at the time when the oil feedstock is brought into contact
with the catalyst and reacted is preferably 1.5 MPaG or lower, and more preferably 1.0
MPaG or lower. When the reaction pressure is 1.5 MPaG or lower, it is possible to
prevent light gas from being additionally generated and to diminish pressure resistance of
the reaction device. Though not particularly limited, the lower limit of the reaction
! 10 pressure is preferably equal to or higher than normal pressure in view of cost and the
like.
[0024]
[Contact time]
The time for which the oil feedstock comes into contact with the catalyst is not
15 particularly limited as long as a substantially desired reaction is caused. For example,
the contact time is preferably 1 to 300 sec in terms of the time required for gas on the
catalyst to pass. The lower limit of the contact time is more preferably 5 sec or longer,
and the upper limit thereof is more preferably 150 sec or shorter. When the contact time .
is 1 sec or longer, the reaction can be caused reliably, and when it is 300 sec or shorter, it
20 is possible to inhibit a carbonaceous substance from being accumulated onto the catalyst
I by coking or the like and to suppress the amount of light gas generated by cracking.
I [0025]
I In the production method of monocyclic aromatic hydrocarbon of the present
I embodiment, the oil feedstock is brought into contact with an acid point of the catalyst to
i
| 25 cause various reactions such as cracking, dehydrogenation, cyclization, and hydrogen
I
!
i
% 15
transfer and cause ring opening of polycyclic aromatic hydrocarbon, thereby obtaining
monocyclic aromatic hydrocarbon.
In the present embodiment, the yield of monocyclic aromatic hydrocarbon is
preferably 15 mass% or more, more preferably 20 mass% or more, and even more
5 preferably 25 mass% or more. If the yield of monocyclic aromatic hydrocarbon is less
than 15 mass%, this is not preferable since the concentration of the target substance in
the product decreases, and collecting efficiency is lowered.
[0026]
The production method of the present embodiment described above uses the
10 catalyst described above. Accordingly, with this method, it is possible to produce
monocyclic aromatic hydrocarbon with a high yield and to prevent the reduction in the
yield of monocyclic aromatic hydrocarbon caused over time.
Example
[0027]
15 Hereinafter, the present invention will be described in more detail based on
I examples and comparative examples, but the present invention is not limited to these
I examples.
[0028]
(Example 1)
20 A solution (A) containing 1706.1 g of sodium silicate (J sodium silicate No. 3,
SiCh: 28 to 30 mass%, Na: 9 to 10 mass%, balance: water, manufactured by Nippon
chemical industrial Co., LTD.) and 2227.5 g of water and a solution (B) containing 64.2 g
of Ai2(S04)3-14 to 18 H2O (special grade chemical, manufactured by Wako Pure
Chemical Industries, Ltd.), 369.2 g of tetrapropylammonium bromide, 152. 1 g of H2SO4
25 (97 mass%), 326.6 g of NaCl, and 2975.7 g of water were prepared respectively.
}
S
[0029]
i
I Subsequently, while the solution (A) was being stirred at room temperature, the
solution (B) was slowly added to the solution (A).
The obtained mixture was vigorously stirred with a mixer for 15 minutes to
5 crack the gel, whereby the mixture was put in the state of a homogenous fine emulsion.
Thereafter, the mixture was put in a stainless steel autoclave and subjected to
crystallization operation under a self-pressure in natural course of events, a temperature
of 160°C and a stirring speed of 100 rpm for 72 hours. After the crystallization
operation ended, the product was filtered to collect a solid product, and the operation in
10 which the solid product was washed with about 5 L of deionized water and filtered was
repeated 5 times. The solid content separated and obtained by filtration was dried at
120°C and baked for 3 hours at 550°C under an air flow.
[0030]
X-ray diffraction analysis (name of instrument: Rigaku RINT-2500V) was
15 performed on the obtained baked product, and as a result, it was confirmed that the
product has an MFI structure. Moreover, a SiCVAkCb ratio (molar ratio) confirmed by
X-ray fluorescence analysis (name of instrument: Rigaku ZSXIOle) was 64.8. In
addition, the content of aluminum element contained in the lattice skeleton that was
calculated from the above result was 1.32 mass%.
20 A 30 mass% aqueous ammonium nitrate solution was added to the obtained
baked product in such a ratio that 5 mL of the solution was added to 1 g of the product.
The mixture was heated for 2 hours at 100°C and stirred, followed by filtration and
washing with water. This operation was repeated 4 times, and then the resultant was
I dried for 3 hours at 120°C, thereby obtaining ammonium-type crystalline aluminosilicate.
!
Thereafter, baking was performed for 3 hours at 780°C, thereby obtaining proton-type
crystalline aluminosilicate.
[0031]
Subsequently, the obtained proton-type crystalline aluminosilicate is
5 impregnated with 30 g of an aqueous diammonium hydrogen phosphate solution such
that 0.2 mass% (value calculated when the total weight of the catalyst is regarded as
being 100 mass%) of phosphorus was contained in 30 g of the proton-type crystalline
! aluminosilicate, followed by drying at 120°C. Thereafter, the resultant was baked for 3
j hours at 780°C under an air flow, thereby obtaining a catalyst containing crystalline
10 aluminosilicate and phosphorus.
In the obtained catalyst, a molar ratio (P/Al ratio) between phosphorus contained
in the crystalline aluminosilicate and aluminum of the crystalline aluminosilicate was
0.14, and the content of phosphorus based on the total weight of the catalyst was 0.2
mass%.
15 [0032]
A pressure of 39.2 MPa (400 kgf) was applied to the obtained catalyst to form
tablets, and the resultant was coarsely pulverized to have a size of 20 to 28 mesh, thereby
obtaining a granular catalyst 1 (hereinafter, called a "granulated catalyst 1").
[0033]
20 (Example 2)
A granular catalyst 2 (hereinafter, called a "granulated catalyst 2") was obtained
in the same manner as in Example 1, except that the concentration of an aqueous
diammonium hydrogen phosphate solution was adjusted such that 0.7 mass% (value
calculated when the total weight of the catalyst is regarded as being 100 mass%) of
25 phosphorus was contained in 30 g of proton-type crystalline aluminosilicate, and the
f
% 18
proton-type crystalline aluminosilicate was impregnated with 30 g of the aqueous
solution.
In the obtained catalyst, a molar ratio (P/Al ratio) between phosphorus contained
in crystalline aluminosilicate and aluminum of crystalline aluminosilicate was 0.50, and
5 the content of phosphorus based on the total weight of the catalyst was 0.7 mass%.
[0034]
(Example 3)
A granular catalyst 3 (hereinafter, called a "granulated catalyst 3") was obtained
in the same manner as in Example 1, except that the concentration of an aqueous
10 phosphoric acid solution was adjusted such that 1.2 mass% (value calculated when the
total weight of the catalyst is regarded as being 100 mass%) of phosphorus is added to 30
g of proton-type crystalline aluminosilicate, and the proton-type crystalline
aluminosilicate is impregnated with 30 g of the aqueous solution.
In the obtained catalyst, a molar ratio (P/Al ratio) between phosphorus contained
15 in the crystalline aluminosilicate and aluminum of the crystalline aluminosilicate was
0.86, and the content of phosphorus based on the total weight of the catalyst was 1.2
mass%.
[0035]
(Example 4)
20 Fumed silica was impregnated with 30 g of an aqueous diammonium hydrogen
phosphate solution such that 16.2 mass% of phosphorus was contained in 18 g of the
fumed silica, followed by drying at 120°C. Thereafter, the resultant was baked for 3
hours at 780°C under an air flow, thereby obtaining phosphorus-containing fumed silica.
18 g of the phosphorus-containing fumed silica was mixed with 12 g of the catalyst 2
25 prepared in Example 2, and a pressure of 39.2 MPa (400 Kgf) was applied to the
^ 19
obtained catalyst to form tablets. The resultant was coarsely pulverized to have a size
of 20 to 28 mesh, thereby obtaining a granular catalyst 4 (hereinafter, called a
"granulated catalyst 4").
In the obtained catalyst, a molar ratio (P/Al ratio) between phosphorus contained
5 in the crystalline aluminosilicate and aluminum of the crystalline aluminosilicate was
0.50, and the content of phosphorus based on the total weight of the catalyst was 10
mass%.
[0036]
(Example 5)
I 10 A mixed solution containing 106 g of sodium silicate (J sodium silicate No. 3,
Si02: 28 to 30 mass%, Na: 9 to 10 mass%, balance: water, manufactured by Nippon
| chemical industrial Co., LTD.) and pure water was added dropwise to diluted sulfuric
I acid, thereby preparing an aqueous silica sol solution (SiCh concentration of 10.2%). In
j addition, distilled water was added to 20.4 g of the catalyst 2 that was prepared in
i
! 15 Example 2 and contained crystalline aluminosilicate and phosphorus, thereby preparing
zeolite slurry. The zeolite slurry was mixed with 300 g of the aqueous silica sol solution,
and the thus prepared slurry was spray-dried at 250°C, thereby obtaining a spherical
catalyst. Thereafter, the catalyst was baked for 3 hours at 600°C, thereby obtaining a
catalyst 5 having a powder shape (hereinafter, called a "powdery catalyst 5") that had an
20 average particle size of 84 urn and a bulk density of 0.74 g/cc.
In the obtained catalyst, a molar ratio (P/Al ratio) between phosphorus contained
in the crystalline aluminosilicate and aluminum of the crystalline aluminosilicate was
0.50, and the content of phosphorus based on the total weight of the catalyst was 0.28
mass%.
.25 [0037]
S
^ 20
(Comparative example 1)
A granular catalyst 6 (hereinafter, called a "granulated catalyst 6") was obtained
in the same manner as in Example 1, except that the concentration of an aqueous
diammonium hydrogen phosphate solution was adjusted such that 2.0 mass% (value
5 calculated when the total weight of the catalyst is regarded as being 100 mass%) of
phosphorus was contained in 30 g of proton-type crystalline aluminosilicate, and the
crystalline aluminosilicate was impregnated with 30 g of the aqueous solution.
In the obtained catalyst, a molar ratio (P/Al ratio) between phosphorus contained
in the crystalline aluminosilicate and aluminum of the crystalline aluminosilicate was
10 1.43, and the content of phosphorus based on the total weight of the catalyst was 2.0
mass%.
[0038]
(Comparative example 2)
A granular catalyst 7 (hereinafter, called a "granulated catalyst 7") was obtained
15 in the same manner as in Example 1, except that proton-type crystalline aluminosilicate
was used as it was.
[0039]
The catalytic activity of the obtained granulated catalyst at the initial stage of
reaction and after hydrothermal deterioration was evaluated as below.
20 [0040]
[Evaluation of catalytic activity at the initial stage of reaction: Evaluation 1]
By using a circulation-type reaction device including a reactor filled with the
granulated catalysts 1 to 4, 6, and 7(10 ml) respectively, the oil feedstock having
properties shown in Table 1 was brought into contact with the granulated catalyst and
25 reacted, at a reaction temperature of 550°C and a reaction pressure of 0 MPaG. At this
• 21
time, nitrogen as a diluent was introduced into the device such that oil feedstock came
into contact with the granulated catalyst for 7 seconds.
The reaction was caused for 30 minutes under the above conditions, thereby
producing monocyclic aromatic hydrocarbon having 6 to 8 carbon number. By using an
5 FID gas chromatograph directly connected to the reaction device, the composition of the
product was analyzed to evaluate the catalytic activity at the initial stage of the reaction.
The evaluation results are shown in Table 2 A to 2C.
In Table 2A to 2C a heavy fraction in the product refers to hydrocarbon that is
not included in monocyclic aromatic hydrocarbon having 6 to 8 carbon number and has 6
10 or more carbon number, light naphtha refers to hydrocarbon having 5 to 6 carbon number,
liquefied petroleum gas refers to hydrocarbon having 3 to 4 carbon number, and cracked
gas refers to hydrocarbon having 2 or less carbon number.
[0041]
[Evaluation of catalytic activity after hydrothermal deterioration: Evaluation 2]
15 Each of the granulated catalysts 1 to 4 and 7 was subjected to hydrothermal
treatment at a treatment temperature of 650°C for a treatment time of 6 hours in an
environment of 100 mass% of water vapor, thereby preparing pseudo-deteriorated
catalysts 1 to 4 and 7 that were caused to undergo pseudo-hydrothermal deterioration.
The oil feedstock was reacted in the same manner as in Evaluation 1, except that
20 the pseudo-deteriorated catalysts 1 to 4 and 7 were used respectively instead of the
granulated catalysts 1 to 4 and 7. The composition of the thus obtained products was
analyzed to evaluate the catalytic activity after hydrothermal deterioration. The
evaluation results are shown in Table 2A to 2C.
[0042]
25 [Evaluation of yield of monocyclic aromatic hydrocarbon at the initial stage of
It* 22
reaction: Evaluation 3]
By using a circulation-type reaction device including a reactor filled with the
powdery catalyst 5 (400 g), the oil feedstock having properties shown in Table 1 was
brought into contact with the powdery catalyst 5 and reacted, at a reaction temperature of
5 550°C and a reaction pressure of 0.1 MPaG. At this time, the powdery catalyst was
filled in a reaction tube having a diameter of 60 mm. As a diluent, nitrogen was
introduced into the device such that the oil feedstock came into contact with the powdery
catalyst for 10 seconds.
The reaction was caused for 10 minutes under the above condition, thereby
10 producing monocyclic aromatic hydrocarbon having 6 to 8 carbon number. By using an
FID gas chromatograph directly connected to the reaction device, the composition of the
product was analyzed to evaluate the catalytic activity at the initial stage of the reaction.
The evaluation results are shown in Table 2B.
In Table 2B, a heavy fraction in the product refers to hydrocarbon that is not
15 included in monocyclic aromatic hydrocarbon having 6 to 8 carbon number and has 6 or
more carbon number, light naphtha refers to hydrocarbon having 5 to 6 carbon number,
liquefied petroleum gas refers to hydrocarbon having 3 to 4 carbon number, and cracked
gas refers to hydrocarbon having 2 or less carbon number.
[0043]
20 [Evaluation of catalytic activity after hydrothermal deterioration: Evaluation 4]
The powdery catalyst 5 was subjected to hydrothermal treatment at a treatment
temperature of 650°C for a treatment time of 6 hours in an environment of 100 mass% of
water vapor, thereby preparing pseudo-deteriorated catalyst 5 that was caused to undergo
pseudo-hydrothermal deterioration.
25 The oil feedstock was reacted in the same manner as in Evaluation 3, except that
# 23
the pseudo-deteriorated catalyst 5 was used instead of the powdery catalyst 5. The.
composition of the thus obtained product was analyzed to evaluate the catalytic activity
after hydrothermal deterioration. The evaluation results are shown in Table 2B.
[0044]
5 [Catalyst deterioration]
A value of the amount (mass%) of monocyclic aromatic hydrocarbon having 6
to 8 carbon number in the evaluation (Evaluation 2 or 4) of catalytic activity after
hydrothermal deterioration with respect to a value of the amount (mass%) of monocyclic
aromatic hydrocarbon having 6 to 8 carbon number in the evaluation (Evaluation 1 or 3)
10 of catalytic activity at the initial stage of the reaction ([amount (mass%) of monocyclic
aromatic hydrocarbon having 6 to 8 carbon number in Evaluation 2 (or 4)] / [amount
(mass%) of monocyclic aromatic hydrocarbon having 6 to 8 carbon number in
Evaluation 1 (or 3)]) was calculated to determine the degree of catalyst deterioration.
The results are also shown in Table 2A to 2C. The larger value means that the catalyst
15 hard to deteriorate. In addition, the amount of monocyclic aromatic hydrocarbon
having 6 to 8 carbon number will be abbreviated to the amount of monocyclic aromatic
hydrocarbon in some cases.
^ 24
[0045]
[Table 1]
Properties of raw material Method of
analysis
Density (measured at 15°C) I g/cm3 I 0.908 JISK2249
Kinetic viscosity (measured at 30°C) mm2/s 3.645 JIS K 2283
Distillation I Initial boiling point °C 177.5 JIS K 2254
properties 10 volume% distillation °C 226.5
temperature
50 volume% distillation °C 276.0
temperature
90 volume% distillation °C 350.0
temperature
Final point °_C 377.0
Composition Saturated fraction volume% 34 JPI-5S-49
analysis Olefin fraction volume% 8
Total aromatic fraction volmae% 58
Monocyclic aromatic volume% 23
fraction
Bicyclic aromatic volume% 26
fraction
Aromatic fraction volume% 9
having 3 or more rings
# 25
[0046]
| [Table 2A]
! Method of preparing „ . , „ . „ „ , .
i i f i 4. Example 1 Example 2 Example 3
granular catalyst
Phosphorus contained in
crystalline
aluminosilicate/aluminum
of crystalline 0.14 0.5 0.86
aluminosilicate
(P/Al ratio)
(molar ratio)
Content of phosphorus
based on weight of
catalyst °-2 °-7 !-2
(mass%)
Evaluation _ . . . Evaluation _ . . _ Evaluation „ . . -
. Evaluation 2 . Evaluation 2 1 Evaluation 2
„ , . , Pseudo „ . . , Pseudo „ . . , Pseudo
„ . . . Granulated , ^ . . , Granulated , . . ^ , Granulated , ^ . ^ , Catalyst . . . , -deteriorated . . . _ -deteriorated . . . J catalyJ st 1 ca.t al, yst. ,1 catalyst 2 ca.t al,y st. .2, catalJy st 3_ c-adt,ea tl,ey rsiot ,r3a, ted
" e a ^ y 46 53 47 50 52 52
traction
Monocyclic
aromatic
Generated hydrocarbon 3g ^ ^ 3Q 22 ^
amount having 6 to
8 carbon
number
(mass%) Llg!", 1 1 1 1 2 1
v ' naphtha .
Liquefied
petroleum 4 9 8 8 14 13
gas
Cracked gas 8 9 9 9 11 11
Hydrogen 1 1 1 1 0 0
Amount (mass%) of
monocyclic aromatic
hydrocarbon in
Evaluation 2 (or 4) /
amount (mass%) of 0.69 0.9 1.06
monocyclic aromatic
hydrocarbon in
Evaluation 1 (or 3)
(mass%)
^ 26
[Table 2B]
Method of preparing _ . . „ , „
. f, . Example 4 Example 5
granular catalyst r r
Phosphorus contained in
crystalline
aluminosilicate/aluminum
of crystalline 0.5 0.5
aluminosilicate
(P/Al ratio)
(molar ratio)
Content of phosphorus
based on weight of
catalyst 10 °-28
(mass%)
Evaluation „ . ,. „ Evaluation _ , ^.
. Evaluation 2 . Evaluation 4
„ . Granulated Pseudo-deteriorated Powdered Pseudo-deteriorated
catalyst 4 catalyst 4 catalyst 5 catalyst 5
" e a 7 50 53 48 50
fraction
Monocyclic
aromatic
Generated hydrocarbon .. »- ,, 00
i • ^ . 25 22 j I 2o
amount having 6 to
8 carbon
number
(mass%) Llg^ , 1 1 11
naphtha
Liquefied
petroleum 15 14 9 10
gas ;
Cracked gas 11 10 - 11 11
Hydrogen 1 1 11
Amount (mass%) of
monocyclic aromatic
hydrocarbon in
Evaluation 2 (or 4) /
amount (mass%) of 0.96 0.9
monocyclic aromatic
hydrocarbon in
Evaluation 1 (or 3)
(mass%)
^t? 27
[Table 2C]
i ill* Comparative example 1 Comparative example 2
granular catalyst r r r r
Phosphorus contained in
crystalline
aluminosilicate/aluminum
of crystalline \ 43 0.0
aluminosilicate
(P/Al ratio)
(molar ratio)
Content of phosphorus
based on weight of
catalyst 2-° °-°
(mass%)
Evaluation Evaluation Evaluation _ , ,.
. . . Evaluation 2
„ . Granulated Granulated Pseudo-deteriorated
y catalyst 6 catalyst 7 catalyst 7
| " e a 7 58 - 46 62
fraction
Monocyclic
aromatic
Generated hydrocarbon ,„ -
amount having 6 to
8 carbon
number
(mass%) Llg^ . 6 - 1 4
v y naphtha
Liquefied
petroleum 21 - 5 15
gas
Cracked gas 10 - .9 9
Hydrogen 0 - 1 0
Amount (mass%) of
monocyclic aromatic
hydrocarbon in
Evaluation 2 (or 4) /
amount (mass%) of . Q 26
monocyclic aromatic
hydrocarbon in
Evaluation 1 (or 3)
(mass%)
[0047]
[Result]
5 In Examples 1 to 5 using the granulated catalysts 1 to 4 and powdery catalyst 5,
the amount of monocyclic aromatic hydrocarbon having 6 to 8 carbon number generated
at the initial stage of the reaction was 39 mass%, 34 mass%, 22 mass%, 23 mass%, and
tO 28
31 mass% respectively, and the amount of monocyclic aromatic hydrocarbon having 6 to
8 carbon number generated after hydrothermal deterioration was 27 mass%, 30 mass%,
23 mass%, 22 mass%, and 28 mass% respectively. In addition, the degree of catalyst
deterioration ([amount (mass%) of monocyclic aromatic hydrocarbon in Evaluation 2 (or
5 4)/ amount (mass%) of monocyclic aromatic hydrocarbon in Evaluation 1 (or 3)]) was
0.69, 0.90, 1.06, 0.96, and 0.90 respectively.
It was found that in Examples 1 to 5 using the granulated catalysts 1 to 4 and
powdery catalyst 5, both the catalytic activity at the initial stage of the reaction and the
catalytic activity after hydrothermal deterioration were excellent, and monocyclic
10 aromatic hydrocarbon having 6 to 8 carbon was obtained with an excellent yield at the
initial stage of the reaction and after hydrothermal deterioration, as the object of the
present application.
On the other hand, it was found that in Comparative example 1 using the
granulated catalyst 6 having a high P/Al ratio, the amount of monocyclic aromatic
15 hydrocarbon having 6 to 8 carbon number generated at the initial stage of the reaction
was 5 mass%, and when a large amount of phosphorus was added, the yield of
monocyclic aromatic hydrocarbon having 6 to 8 carbon number in the product markedly
decreased even at the initial stage of the reaction.
In Comparative example 2 using the granulated catalyst 7 having a P/Al ratio of
20 0, the amount of monocyclic aromatic hydrocarbon having 6 to 8 carbon number
generated at the initial stage of the reaction was 38 mass%, the amount of monocyclic
aromatic hydrocarbon having 6 to 8 carbon number generated after hydrothermal
deterioration was 10 mass%, and the degree of catalyst deterioration ([amount (mass%)
of monocyclic hydrocarbon in Evaluation 2 / [amount (mass%) of monocyclic aromatic
25 hydrocarbon in Evaluation 1]) was 0.26. Accordingly, it was found that when a catalyst
# 29
not containing phosphorus is used, though the yield of monocyclic aromatic hydrocarbon
having 6 to 8 carbon number at the initial stage of the reaction is excellent, the yield
decreases after hydrothermal deterioration, and the catalyst deteriorates markedly, so the
catalyst is not practical.
5 [0048]
So far, preferable embodiments of the present invention have been described,
but the present invention is not limited to the above embodiments. Within a scope that
is not extrinsic to the object of the present invention, the constitutional elements can be
added, omitted, substituted, and modified in another way. The present invention is
10 restricted not by the above description but only by the claims attached.

i
I
+ 30
CLAIMS
i
| LA catalyst for producing monocyclic aromatic hydrocarbon that is for producing
i monocyclic aromatic hydrocarbon having 6 to 8 carbon number from oil feedstock
5 having a 10 volume% distillation temperature of 140°C or higher and a 90 volume%
distillation temperature of 380°C or lower, the catalyst comprising:
crystalline aluminosilicate; and
phosphorus,
wherein a molar ratio (P/Al ratio) between phosphorus contained in the
10 crystalline aluminosilicate and aluminum of the crystalline aluminosilicate is from 0.1 to
1.0.
2. The catalyst for producing monocyclic aromatic hydrocarbon according to Claim 1,
wherein the phosphorus content is 0.1 to 10 mass% based on the catalyst weight.
15
3. The catalyst for producing monocyclic aromatic hydrocarbon according to Claim 1
or 2,
wherein the crystalline aluminosilicate is medium pore size zeolite.
20 4. The catalyst for producing monocyclic aromatic hydrocarbon according to any one
of Claims 1 to 3,
wherein the crystalline aluminosilicate is MFI-type zeolite.
5. A production method of monocyclic aromatic hydrocarbon having 6 to 8 carbon
i 25 number,- comprising bringing oil feedstock having a 10 volume% distillation temperature
[
• 31
of 140°C or higher and a 90 volume% distillation temperature of 380°C or lower into
contact with the catalyst for producing monocyclic aromatic hydrocarbon according to
| any one of Claims 1 to 4.
5 6. The production method of monocyclic aromatic hydrocarbon having 6 to 8 carbon
number according to Claim 5,
wherein the oil feedstock includes light cycle oil generated from a fluidized
catalytic cracking.
I 10 7. The production method of a monocyclic aromatic hydrocarbon having 6 to 8 carbon
| number according to Claim 5 or 6, further comprising bringing the oil feedstock into
contact with the catalyst for producing monocyclic aromatic hydrocarbon by using a
fluidized-bed reaction equipment.