Technical field
[0001]
The present invention, chabazite-type zeolite (hereinafter, also referred to as CHA-type zeolite.) And a manufacturing method thereof.
BACKGROUND
[0002]
CHA-type zeolite is a zeolite having CHA structure International Zeolite Association (IZA) defines. CHA-type zeolite is generally an organic structure directing agent as in Patent Document 1 (hereinafter, also referred to as SDA.) Is synthesized by the method used. Further, it is possible to also synthesized by a method that does not use the SDA as in Patent Document 2.
[0003]
　CHA zeolite, for example, the separation of gas, reduction of nitrogen oxides contained in the exhaust gas of an automobile, conversion to liquid fuel lower alcohols and other oxygen-containing hydrocarbons, and a catalyst for the production of dimethylamine it can be used as. In these applications, for utilizing the pores derived from the crystal structure of CHA-type zeolite, there is a need for a high crystallinity CHA-type zeolite.
[0004]
　Furthermore, the CHA-type zeolite, there is a problem that when exposed to a high temperature in the presence of moisture the crystal structure is destroyed (hydrothermal resistance). For example, when used for removal of harmful components in exhaust gas discharged from the reduction and factories of nitrogen oxides contained in the exhaust gas of an automobile, CHA-type zeolite low hydrothermal resistance, since the crystal structure during use is corrupt, You can not influence the performance of the product.
CITATION
Patent Document
[0005]
Patent Document 1: JP 2010-163349
Patent Document 2: JP 2015-101506
Summary of the Invention
Problems that the Invention is to Solve
[0006]
　An object of the present invention is that the crystallinity and hydrothermal resistance provides a high CHA-type zeolite.
Means for Solving the Problems
[0007]
　Silica-alumina ratio and crystallinity are described below CHA-type zeolite in the range of the following (4) By heating in a steam atmosphere conditions with the arrangement (5) (steaming), crystallinity and the hydrothermal resistance is high CHA type zeolite is obtained (hereinafter also referred to as the production method of the present invention.).
　5 ≦ silica-alumina ratio
　100% ≦ crystallinity
Effect of the invention
[0008]
　According to the present invention, it is possible crystallinity and hydrothermal resistance provides a high CHA-type zeolite.
DESCRIPTION OF THE INVENTION
[0009]
[Production process of the present invention]
　the production method of the present invention, a silica-alumina ratio and degree of crystallinity (the CHA-type zeolite before being subjected to the following steaming, also referred to as precursor.) CHA-type zeolite in the range of the steam the processed to crystallinity and hydrothermal resistance is higher CHA-type zeolite (hereinafter the CHA-type zeolite obtained by the process of the present invention, also referred to as zeolites of the present invention.) a method of obtaining. When the CHA-type zeolite to a steam treatment, the crystal structure of CHA-type zeolite, a part of Al is removed. Some from the crystal structure of CHA-type zeolite Al is removed CHA zeolite, the hydrothermal resistance is increased. However, when a portion from the crystal structure of CHA-type zeolite Al is removed, the crystalline structure for damage, crystallinity of the resulting CHA-type zeolite is reduced. Accordingly, by silica-alumina ratio and crystallinity is steamed under specific conditions the CHA-type zeolite in the predetermined range as a precursor, it is possible crystallinity and hydrothermal resistance obtain high CHA-type zeolite. Hereinafter, the manufacturing method of the present invention will be described in detail.
[0010]
　Aforementioned precursor, having the CHA structure. When the above-mentioned precursor has no CHA structure, even if it was steaming, it can not be obtained zeolite of the present invention.
　Incidentally, the presence or absence of the CHA structure can be determined from X-ray diffraction pattern of the above-mentioned precursor. Specifically, if there is a diffraction peaks derived from CHA structure X-ray diffraction pattern of the above-mentioned precursor it can be judged to have a CHA structure. Detailed measurement conditions and the like will be described later.
[0011]
　Silica-alumina ratio of the above-mentioned precursor is in the range below.
　　5 ≦ silica-alumina ratio
　also silica-alumina ratio of the above-mentioned precursor is preferably in the range below. If a silica-alumina ratio is less than 7, since the crystallinity of the zeolite of the present invention obtained by steam treatment is undesirably reduced. Further, if the silica-alumina ratio greater than 15, the hydrothermal resistance is not so improved even if the steam treatment.
　　7 ≦ silica-alumina ratio ≦ 15
　Further, silica-alumina ratio of the aforementioned precursor, and particularly preferably in the range below. When a silica-alumina ratio is steaming the aforementioned precursor in this range, the hydrothermal resistance is further improved.
　　7 ≦ silica-alumina ratio <10
　Note, silica-alumina ratio of the above-mentioned precursors can be calculated from the contents of Si and Al in the aforementioned precursor. Specifically, the weight percent concentration of Si and Al precursors SiO respectively 2 and Al 2 O 3 in terms of molar concentration of, SiO 2 molar concentration of Al 2 O 3 calculated by dividing the molar concentration of It is. Detailed measurement conditions and the like will be described later.
[0012]
　Crystallinity of the foregoing precursors is in the range below.
　　100% ≦ crystallinity
　The crystal of the aforementioned precursor is preferably in the range below.
　　200% ≦ crystallinity
　when crystallinity is steaming less than 100% precursor, the crystallinity of the zeolite of the present invention obtained to become bad. Zeolite lower invention crystallinity degree, since the pores derived from the CHA structure is not sufficiently developed, when used in the catalytic reaction or adsorption reaction utilizing the pores is not preferred because each performance is degraded . Specifically, when used in catalytic reaction utilizing the pores, the catalytic activity and selectivity are lowered. When used for the adsorption reactions utilizing the pores, it may not be selectively adsorb specific chemical adsorption amount is lowered. On the other hand, when steaming the crystallinity is high above the precursor, since the higher the crystallinity of the zeolite of the present invention to be obtained.
　The crystal of the aforementioned precursor is calculated from the X-ray diffraction pattern of the precursor and the standard sample of the present invention. More specifically, of the International Zeolite Association HP (http://www.iza-online.org/synthesis/) or WERIFIED SYNTHESES OF ZEOLITIC MATERIALS "H.Robson ed., KPLillerud XRD Figure: 2001 issue, the second edition, the CHA-type zeolite synthesized based on the method of synthesizing Chabazite to that described in page 123, second page 125 as a standard sample, from the ratio of the height of a particular peak in X-ray diffraction pattern of a standard sample aforementioned precursor It is calculated. Detailed measurement conditions will be described later.
[0013]
　The size of the primary particles of the above precursor is preferably in the range below.
　　Size ≦ 10 [mu] m of 0.05 .mu.m ≦ primary particle
　when the size of the primary particles of the aforementioned precursors 0.05 .mu.m smaller, there is a possibility that the crystallinity of the aforementioned precursor is lower than 100% is not preferable. Further, since the steaming crystals of the aforementioned precursor tends to be destroyed, undesirably may crystallinity of the zeolite of the present invention obtained decreases. If the primary particle size of the above-mentioned precursor is greater than 10 [mu] m, since crystallinity tends to increase preferred. However, the precursor size is 10μm larger than the foregoing primary particles, it is difficult to synthesize.
　The size of the primary particles of the aforementioned precursor, more preferably in the range below.
　　Size ≦ 5 [mu] m of 0.1 [mu] m ≦ primary particle
　aforementioned precursors size of the primary particles is in the above range, the crystal even if the steam treatment is not easily destroyed, high crystallinity of the zeolite of the present invention obtained It preferred to be.
　The size of the aforementioned primary particles is calculated by observing the primary particles with an electron microscope. Specifically, the 10 primary particles from electron micrographs extracted at random, the average value of the major axis of the primary particle size of the primary particles. Detailed measurement conditions and the like will be described later.
[0014]
　The content of alkali metals such as sodium and potassium contained in the above-mentioned precursor is preferably in the range below.
　　0 ppm ≦ alkali metal ≦ 5000 ppm
　alkali metals contained in the aforementioned precursor, be derived from a raw material of the aforementioned precursors are present in a state in which many of ion-exchanged cation site of the CHA-type zeolite ing. Doing the above precursor steam treatment in a state that contains many alkali metal skeleton of the CHA-type zeolite contained in, the reason is not clear, the effect of the steam treatment is small.
　These alkali metals, the precursors of the above H and NH 3 can be removed by ion exchange. Specifically, HCl and NH 4 NO 3 by immersing the precursor of the aforementioned aqueous solution or the like is dissolved, can remove the alkali metal. In the production method of the present invention, NH precursors of the aforementioned 4 NO 3 it is preferred to ion-exchange with an aqueous solution are dissolved. NH 4 NO 3 when the is above an aqueous solution obtained by dissolving the precursor ion exchange, without reducing the crystallinity of the aforementioned precursor, can remove the alkali metal.
[0015]
　Aforementioned precursor preferably contains no P substantially in its crystal structure. Therefore, such SAPO-34 which is one of CHA-type zeolite containing P in the crystal structure is preferably not included in the precursor of the above. Also, P included in the composite material or the like, in some cases remain in the precursor described above. In such a case, if the content of approximately 1000ppm or less, may be interpreted as it is substantially free.
[0016]
　Steaming the foregoing is a process in which the content of water is heated to above the precursor in an atmosphere of 50% or more of the saturated water vapor content.
　　Content of 50% ≦ moisture
　content of the above water is preferably in the range below.
　　Content ≦ 100% of 50% ≦ moisture
　the content of water perform the steam treatment in a state where the range described above, without unduly disrupt the crystal structure of CHA-type zeolite contained in the precursor of the above, the crystal a part of Al can be removed from the structure. The content of water is lower than 50% of the saturated water vapor amount, hardly Al is removed from the crystal structure of CHA-type zeolite contained in the precursor of the above, it is difficult to improve the hydrothermal resistance of the zeolite of the present invention obtained undesirable since. On the other hand, when the content of water is higher than the saturated water vapor content (i.e., if the content of water exceeds 100%), depending on the heating temperature, Al from the crystal structure of CHA-type zeolite contained in the precursor of the above rapidly removed crystal structure is damaged, since the crystallinity of the zeolite of the present invention obtained may be reduced undesirably.
[0017]
　Treatment temperature of the aforementioned steam treatment is in the range below.
　　450 ° C. ≦ treatment temperature ≦ 800 ° C.
　above the processing temperature is preferably in the range below.
　　500 ° C. ≦ treatment temperature ≦ 675 ° C.
　When the above-described treatment temperature to perform steaming in a state where the range described above, without unduly disrupt the crystal structure of CHA-type zeolite contained in the precursor described above, the crystal structure a part of the Al can be removed. Unfavorable treatment temperature described above is lower than 450 ° C., less likely Al is removed from the crystal structure of CHA-type zeolite contained in the precursor of the above, since the hydrothermal resistance of the zeolite of the invention obtained is hardly improved . On the other hand, if the treatment temperature mentioned above is higher than 800 ° C., depending on the content of the above water, the crystal structure is damaged from the crystal structure of CHA-type zeolite Al is rapidly removed to be included in the precursor of the above receiving, since crystallinity of the zeolite of the present invention obtained may be reduced undesirably. The aforementioned content and moisture, to control the appropriate range processing time described later, by slowly removing the Al, it is possible to maintain the crystallinity of the CHA-type zeolite.
[0018]
　The processing time in the above steam treatment is preferably in the range below.
　　0.1 hr ≦ processing time ≦ 48 hr
　aforementioned processing time is shorter than 0.1 hr, Al can not be sufficiently removed from the crystal structure of CHA-type zeolite contained in the precursor of the aforementioned zeolites of the present invention obtained It is not preferable because the hydrothermal resistance is less likely to be improved. On the other hand, the heating time of the aforementioned be longer than 48 hr, it does not change significantly the removal amount of Al from the crystalline structure of CHA-type zeolite contained in the precursor of the above.
　The processing time of the steam treatment in the present invention and is intended to refer to the retention time from reaching the heating temperature.
[0019]
　Atmosphere in the above steam treatment may be conducted under atmospheric, it may be carried out under an inert atmosphere such as nitrogen. Further, in order to keep these atmospheres may perform steam treatment in a closed vessel, it may be performed steam treatment under circulation of air or inert gas. Furthermore, a method of adding moisture to the atmosphere described above, a method of water was vaporized and mixed with the gas, a method of charging the pre-water to the reaction vessel, and a method of charging in a state moistened with water in the precursor, the water or as long as it is a method that can be added.
[0020]
　Steaming the foregoing, muffle furnace, tube furnace, can be carried out by a known method such as kiln, it can be similarly steaming using either.
[0021]
　Foregoing precursors may be obtained by a conventional manufacturing method. For example, as described in Patent Document 1 described above, Si raw material, Al material and an organic structure directing agent an aqueous solution containing (SDA) can be obtained by a method of hydrothermal treatment. Further, as in Patent Document 2 described above, it is also possible to obtain an aqueous solution containing a FAU-type zeolite and potassium compound in a way that hydrothermal treatment. The latter method, in that it does not use the SDA, excellent economy.
[0022]
　Zeolites of the present invention, Al removed from the crystal structure by steam treatment, remaining outside of the crystal structure. Although either Al is present in any state it is unknown, Al 2 O 3 , Al (OH) 3 is believed to be present in the form of compounds such as. Al remaining outside of such a crystal structure, for example by methods such as acid treatment, can be removed if necessary. Specifically, by dipping the zeolite of the present invention in an acid solution, it is possible to remove the Al remaining outside of the crystal structure.
[0023]
[Zeolites of the present invention]
　zeolites of the present invention is obtained by the aforementioned method of the present invention. Hereinafter, the zeolite of the present invention will be described in detail.
[0024]
　Zeolites of the present invention comprises a CHA-type zeolite. Also, the zeolite of the present invention, since a part of the crystal structure of CHA-type zeolite Al is removed by steam treatment, high hydrothermal resistance. Also, the zeolite of the present invention, since the silica-alumina ratio and crystallinity are obtained by steaming a precursor in the range described above, a high crystallinity.
[0025]
　CHA-type zeolite contained in the zeolite of the present invention, since the comparison from the crystal structure and Si is part of the ionic radius larger Al has been removed, as compared to the pre-steaming, the lattice constant becomes smaller. Specifically, the lattice constant of the zeolite of the present invention is in the range below.
　　13.74A ≦ lattice constant
　The lattice constant of the zeolite of the present invention is preferably in the range below.
　　13.50A ≦ lattice constant ≦ 13.72A
　zeolite lattice constant 13.74Å larger than the present invention is not preferable because there is a possibility that hydrothermal resistance is low. CHA-type zeolite low hydrothermal resistance, the catalyst (eg, NH used in high-temperature, high-humidity environment 3 NO by x for removing reaction: NH 3 . Also called -SCR reaction) is used in, CHA structure is destroyed Runode, the catalytic activity tends to decrease.
　On the other hand, zeolite lattice constant 13.50Å less present invention, although the hydrothermal resistance is high, since the degree of crystallinity is likely to be low is not preferable. Also, if the lattice constant is to use a zeolite of 13.50Å smaller the present invention as an adsorbent, for crystallization took considerably contracted state is not preferable because the compound to be adsorbed is less likely to diffuse into the crystal structure. Moreover, the zeolite of the present invention, the need, the cationic site there is a case to be replaced by cations such as Cu and Fe, the lattice constant and 13.50Å smaller, these cations within the crystal structure to become less likely to spread, which is not preferable.
　Incidentally, the lattice constant of the zeolite of the present invention can be calculated from the X-ray diffraction pattern. Specifically, look for the diffraction peaks from the X-ray diffraction pattern of the zeolite of the present invention is attributed to the (2-10) (3-1-1) plane of the CHA structure, is calculated from the values of 2θ of the peak . Detailed measurement conditions and the like will be described later.
[0026]
　Zeolites of the present invention include Si and Al. The content of Si and Al of the zeolite of the present invention, in terms of oxide (Si is SiO 2 conversion, Al is Al 2 O 3 equivalent) in, preferably in the range below.
　　80.5 wt% ≦ Si content ≦ 90
　　wt% of the content of ≦ 19.5 wt% of 10 wt% ≦ Al
　The content of Si and Al of the zeolite of the present invention is measured by ICP emission spectrometry can do. Detailed measurement method will be described later.
[0027]
　Zeolites of the present invention preferably contains no P substantially in its crystal structure. Therefore, such SAPO-34 which is one of CHA-type zeolite containing P in the crystal structure is preferably not included in the zeolite of the present invention. However, the need, if carrying the P outside the crystal structure is. Also, P included in the composite material or the like, sometimes remaining in the zeolite of the present invention. In such a case, if the content of approximately 1000ppm or less, may be interpreted as it is substantially free.
[0028]
　Silica-alumina ratio of the zeolite of the present invention is preferably in the range below.
　　7 ≦ silica-alumina ratio <15
　zeolite of the present invention in which silica-alumina ratio is within the above range, NH 3 when used in -SCR reaction, excellent in catalytic activity and durability. The method of measuring the silica-alumina ratio of the zeolite of the present invention will be described later.
[0029]
　Crystallinity of the zeolite of the present invention is in the range below.
　140% ≦ crystallinity
　when crystallinity of the zeolite of the present invention is too low, because CHA structure is not fully developed, is not preferable because the catalytic activity is lowered when used as a catalyst. Moreover, crystallinity of the zeolite of the invention, more preferably in the range below.
　200% ≦ crystallinity of ≦ 300%
if the crystallinity of the zeolite of the present invention is in the above range, the catalytic activity is particularly excellent when used as a catalyst.
[0030]
　Pore volume of the zeolite of the present invention (PV) is preferably in the range below.
　　0.2 ml / g ≦ pore volume ≦ 0.4 ml / g
　zeolite of the present invention that the pore volume is in the above range, when used as an adsorbent is preferable because the adsorption amount increases. Even when used as a catalyst, excellent catalytic activity and selectivity.
　Incidentally, the pore volume is calculated from the adsorption isotherm obtained by nitrogen adsorption measurements. Detailed measurement conditions will be described later.
[0031]
　The specific surface area of the zeolite of the present invention is preferably in the range below.
　　350 meters 2 / g ≦ specific surface area ≦ 600 meters 2 / g
　when a specific surface area is too low is not preferable because the catalytic activity is lowered. A specific surface area of 600 meters 2 zeolites of the present invention over a / g, the synthesis is difficult.
　The specific surface area is calculated from the adsorption isotherm obtained by nitrogen adsorption measurements. Detailed measurement conditions will be described later.
[0032]
　Zeolites of the present invention, as described above, since the porous by steam treatment tends to external surface area is increased. External surface area of the zeolite of the present invention is preferably in the range below.
　　7m 2 / g ≦ outside surface area ≦ 20 m 2 / g
　outside zeolite surface area is large present invention, when used as a catalyst, excellent catalytic activity.
　The outer surface area is calculated from the adsorption isotherm obtained by nitrogen adsorption measurements. Detailed measurement conditions will be described later.
[0033]
　The size of the primary particles of the zeolite of the present invention is preferably in the range below.
　　Size ≦ 10 [mu] m of 0.05 .mu.m ≦ primary particles
　because the size of the primary particles of the zeolite of the present invention may 0.05 .mu.m smaller, the crystallinity of the zeolite of the present invention may become less than 100% is not preferable. The size is small CHA-type zeolite primary particles, because they tend hydrothermal resistance is low, that is preferably larger primary particle size as possible. However, zeolites of the present invention the size of the primary particles than 10μm are difficult to synthesize.
　The size of the primary particles of the zeolite of the invention, more preferably in the range below.
　　Size ≦ 5 [mu] m of 0.1 [mu] m ≦ primary particle
　zeolite of the present invention the size of the primary particles is in the above range is preferable because crystallinity and hydrothermal resistance is increased.
　The size of the aforementioned primary particles is calculated by observing the primary particles with an electron microscope. Specifically, the 10 primary particles from electron micrographs extracted at random, the average value of the major axis of the primary particle size of the primary particles. Detailed measurement conditions and the like will be described later.
[0034]
　When using the zeolite of the present invention the adsorbent and a catalyst such as, Sr, Cr, Mn, Fe , Co, Ce, Ni, Cu, Zn, Ga, Mo, Ru, Rh, Pd, Ag, In, Sn, Re , Ir, and Pt or the like (additional element) may contain in the following ranges.
　　2 mass% ≦ additional element ≦ 10 wt%
　Also, additional elements described above, may be supported on the surface of the zeolite of the present invention, the ion exchange sites of the zeolite of the present invention may be ion-exchanged. Additive elements mentioned above, the zeolite applications of the invention are suitably selected from the additive elements described above. For example, when used in catalysts for the reduction of the zeolite nitrogen oxides contained in the exhaust gas of an automobile of the present invention preferably contains Cu or Fe, Cu and Fe ion exchange of the zeolite of the present invention it is more preferable that the ion-exchange sites. Zeolites of the present invention Cu and Fe was ion-exchanged to the ion-exchange sites, excellent reducing activity of nitrogen oxides. As a method of zeolite carrying the additional element of the present invention may be a conventionally known ion-exchange methods. Further, after the zeolite of the present invention was immersed in a solution containing an additive element described above, it is also possible to use a method of evaporation to dryness. Furthermore, after the zeolite of the present invention was immersed in a solution containing an additive element described above, it is also possible to use a method of spray drying.
Example
[0035]
　Will be described in further detail by examples present invention, the present invention is not limited to these examples.
[0036]
[Precursor (1) a step of preparing
　a] Al 2 O 3 concentration of 22 wt%, Na 2 O concentration of 17 mass% of aqueous sodium aluminate solution 0.168kg, NaOH concentration 21.65% by weight aqueous sodium hydroxide 1 It added and dissolved while stirring .35Kg, and cooled to 30 ° C.. While stirring the solution, SiO 2 concentration of 24 wt%, Na 2 were added to the O concentration 7.7 wt% aqueous solution of sodium silicate 1.361Kg. The composition of the solution at this time, an oxide molar
　ratio, Na 2 O / Al 2 O 3 =
　16 SiO 2 / Al 2 O 3 = 15
　H 2 O / Al 2 O 3 = 330
was. It was then prepared aluminosilicate solution the solution 15 hours standing to at 30 ° C. The.
[0037]
　SiO 2 concentration of 24 wt%, Na 2 O concentration of 7.7% by weight of water 5.66kg sodium silicate solution 22.78kg and SiO 2 concentration of 30 wt% silica sol (JGC Catalysts and Chemicals Ltd.: Cataloid SI-30: average particle diameter 10 nm) and 18.97Kg, the aluminosilicate solution 2.88kg was added and stirred for mixing. This, Al 2 O 3 concentration of 22 wt%, Na 2 O-concentration of 17 wt% aqueous sodium 10.03kg aluminate added and aged for 3 hours at room temperature, the mixture hydrogel slurry was prepared. Composition of the mixed hydrogel slurry at this time, an oxide molar
　ratio, Na 2 O / Al 2 O 3 =
　2.80 SiO 2 / Al 2 O 3 = 8.70
　H 2 O / Al 2 O 3 = 108
in there were.
[0038]
　The mixture hydrogel slurry 60.3kg at crystallization vessel, 35 hours at 95 ° C., and treated hydrothermally. After cooling to 70 ° C., to obtain a cake 29.5kg of Na-Y type zeolite was filtered. The resulting cake of Na-Y type zeolite, and further washed, filtered to prepare a Na-Y type zeolite was dried.
[0039]
　Na-Y zeolite 500 g, an aqueous solution 5000g comprising ammonium sulfate 280g was heated to 80 ° C., after stirring for 2 hours while ion exchange, filtered, washed, dried, and calcined 5 hours at 550 ° C.. Further, ion-exchanged with the above conditions, filtration, washing, an operation of drying performed twice, NH 4 ion exchange ratio 95% 0.95 (NH 4 ) 2 O · 0.05Na 2 O · Al 2 O 3 · 5SiO 2 zeolite (NH 4 (95) also referred to as a Y-type zeolite.) was prepared.
[0040]
　NH 4 (95) filled with a Y-type zeolite in the reaction vessel, the water content in the reaction vessel was added water to give 100% saturated steam amount. Then, after the temperature was raised to 600 ° C., by holding for 2 hours to prepare a super stability FAU type zeolite.
[0041]
　This ultra stable FAU type zeolite 500 g, concentration 25% by weight of 495g sulfuric performed dropwise to dealumination treatment with 0.5 hours to prepare a FAU type zeolite silica-alumina ratio 9.0.
[0042]
　The concentration of the FAU-type zeolite is prepared FAU type zeolite slurry is 20 wt%, a bead mill (Ashizawa Fine Tech Co., Ltd.: LMZ015) at was pulverizing treatment. Refining conditions at this time, zirconia beads 0.5 mm, peripheral speed 10 m / s, bead loading was 85% in terms of volume. Mixing the finely divided FAU type zeolite slurry 95g of water 60 g, followed by mixing KOH5.5g concentration 95.5 wt%, was synthesized slurry was prepared. The synthesis slurry was heat treated for 48 hours water at 0.99 ° C.. Then, take out the synthesis slurry hydrothermal treatment, filtration, washing and drying to prepare a CHA-type zeolite.
[0043]
　The resulting CHA-type zeolite 100 g, was added to the aqueous solution 1000g comprising ammonium sulfate 100 g, it was heated to 60 ° C., after 1 hour the ion-exchange with stirring, filtered, washed and dried. Further, ion-exchanged with the above conditions, filtration, washing, an operation of drying performed twice, NH 4 was prepared ion exchange rate of 99% of the CHA-type zeolite, was this the precursor (1).
[0044]
　The obtained precursor (1) was measured the presence of CHA structure in the following manner. The results are shown in Table 1.
[Presence of CHA structure]
obtained precursor for (1), the X-ray diffraction measurement under the following conditions, to determine the presence or absence of CHA structure from criteria below.

device MiniFlex (manufactured by Rigaku Corporation)
operating shaft 2 [Theta] / theta
-ray source CuKα
measurement method continuous
voltage 40kV
current 15mA
start angle 2 [Theta] = 5 °
end angle 2 [Theta] = 50 °
sampling width 0.020 °
Scanning speed 10.000 ° / min

　X-ray diffraction pattern obtained by the above measurement, (100), (200), (20-1), (21-1), (211), (3-1 -1), (310), it is determined that the case has a CHA structure having all of the peak attributed to Miller index (3-1-2).
[0045]
　The resulting precursor for (1) was measured silica-alumina ratio in the following manner. Further, combined also measured content of alkali metal and P to. The results are shown in Table 1.
[Measurement method of silica-alumina ratio]
　Si, Al, the content of the alkali metal and P was measured by the following conditions. The content of each component was calculated in% by weight in terms of the respective oxides (Si is SiO 2 conversion, Al is Al 2 O 3 in terms of the alkali metal M 2 O in terms of: M = an alkali metal, P is P 2 O 5 equivalent). Further, SiO calculated 2 and Al 2 O 3 in terms of the content of the molar ratio, silica-alumina ratio (SiO 2 / Al 2 O 3 were calculated).

Measurement method: ICP emission spectrometry
apparatus: ICP730-ES (Ltd. VARIAN)
Sample dissolved: acid dissolution
[0046]
　The obtained precursor (1) was measured crystallinity in the following manner. The results are shown in Table 1.
[Measurement method of crystallinity]
　was synthesized based on the method of synthesizing Chabazite described in HP (http://www.iza-online.org/synthesis/) of the International Zeolite Association. Specifically, the addition of HY type zeolite 25.0g of silica-alumina ratio of 5.2 ion exchange water and 45 weight percent KOH solution 198.2ml in 26.8ml mixed solution was stirred for 30 seconds. The slurry was 96 hours crystallize at 95 ° C.. The resulting slurry was washed twice with water 500 ml, and dried to obtain a standard substance.
　For standard precursor (1) obtained by the above method, X-ray diffraction measurement was carried out under the following conditions.

device MiniFlex (manufactured by Rigaku Corporation)
operating shaft 2 [Theta] / theta
-ray source CuKα
measurement method continuous
voltage 40kV
current 15mA
start angle 2 [Theta] = 5 °
end angle 2 [Theta] = 50 °
sampling width 0.020 °
Scanning speed 10.000 ° / min
　from X-ray diffraction pattern obtained by X-ray diffraction measurement described above, the Miller index (100), (20-1), high in the peak attributed to (3-1-1) seeking the total value was determined crystallinity by the following equation.
Crystallinity [%] = H / H R　× 100
H: Sum of the precursor (1) above each peak height of
H R : Sum of each peak height of the standard substance
[0047]
　The obtained precursor (1) was measured for the primary particle size under the following conditions. The results are shown in Table 1.
[Primary particle size measuring conditions]
　The obtained precursor (1) was subjected to electron microscopic observation under the following conditions. Incidentally, the magnification if the magnification size of the primary particles can be confirmed, may not necessarily under the following conditions. From the obtained image was measured the size of the primary particles.

　measuring apparatus JEOL JEOL JSM-7600
　accelerating voltage 1.0kV
　magnification of 20,000 times

　randomly extracts ten primary particles from an electron microscope image, the the average value of the long diameter of the primary particle was the size of the primary particles.
[0048]
[Example 1]
　Precursor (1) was filled with 100g in the reaction vessel, the water content in the reaction vessel was added water to give 100% saturated steam amount. Then, after the temperature was raised to 800 ° C., and held for 20 minutes to obtain a CHA-type zeolite
[0049]
　For CHA-type zeolite obtained in Example 1, under the conditions described above, the presence or absence of chabazite structure, silica-alumina ratio was measured the size and crystallinity of the primary particles. The results are shown in Table 2.
[0050]
　For CHA-type zeolite obtained in Example 1 was measured to measure the lattice constants under the following conditions. The results are shown in Table 2.
[Measurement method for the lattice
constant]
　standard sample titanium oxide (anatase)
　mixing ratio CHA-type zeolite of the standard sample: titanium oxide = 5: 1
　device MiniFlex (manufactured by Rigaku Corporation)
　operating shaft 2 [Theta] / theta
　-ray source CuKα
　measurement method continuous
　voltage 40kV
　current 15mA
　start angle 2 [Theta] = 5 °
　end angle 2 [Theta] = 50 °
　sampling width 0.020 °
　scanning speed 10.000 ° / min

　Rigaku integrated X-ray powder analysis software PDXL to thereby read the measurement data, the data processing was performed in the default condition. Then, specify a space group attributed to a chabazite structure was calculated lattice constants (size of a-axis) using a Miller index (2-10) (3-1-1). Incidentally, the lattice constant of the foregoing, the titanium oxide as a standard sample was calculated by correcting the angle.
[0051]
　For CHA-type zeolite obtained in Example 1, it was subjected to pore volume and external surface area measured under the following conditions. The results are shown in Table 2.
[Pore volume and external surface area measurement method]
　Measurement method nitrogen adsorption method
　measuring device BEL SORP-miniII (manufactured by Microtrac Bell Inc.)
　Sample weight: about 0.05g
　pretreatment 300 ° C., 2 hours (under vacuum)
　relative pressure range 0-1.0
　method of calculating the total pore volume: 0.990
　　　　　　　specific surface area, external surface area: t-plot method
[0052]
　For CHA-type zeolite obtained in Example 1 was evaluated in hydrothermal resistance under the following conditions. Specifically, the CHA-type zeolite obtained in Example 1 was steamed, Miller index of X-ray diffraction pattern before and after steam treatment (100), (20-1), (3-1-1) by comparing the sum of the height of the peak attributed to, and evaluated by calculating the crystallinity retention. Table 2 shows the results
[Evaluation method of hydrothermal resistance]
　The CHA-type zeolite obtained in Example 1 was steamed under the following conditions.

　apparatus annular furnace
　temperature 700 ° C.
　3 hours time
　gas H 2 to O at a rate of 1 ml / min, flow in a tube furnace
　for CHA-type zeolite after steaming in the same way as the above-mentioned measurement method of crystallinity , Miller indices of CHA-type zeolite obtained in example 1 (100), (20-1) to calculate the total value Hsteam the height of each peak attributed to (3-1-1).

　H after the aforementioned steaming the H obtained by the measurement of the crystallinity of the foregoing embodiments 1 ? Steam was used to calculated from the following equation.
Crystallinity retention [%] = H ? Steam / H × 100
[0053]
Example 2
　Precursor (1) was filled with 100g in the reaction vessel, the water content in the reaction vessel was added water to give 100% saturated steam amount. Then, after the temperature was raised to 750 ° C., and held for 20 minutes to obtain a CHA-type zeolite. Further, the obtained CHA-type zeolite, was evaluated in the same manner as in Example 1. The results are shown in Table 2.
[0054]
Example 3
　Precursor (1) was filled with 100g in the reaction vessel, the water content in the reaction vessel was added water to give 100% saturated steam amount. Then, after the temperature was raised to 700 ° C., and held for 20 minutes to obtain a CHA-type zeolite. Further, the obtained CHA-type zeolite, was evaluated in the same manner as in Example 1. The results are shown in Table 2.
[0055]
Example 4
　precursor (1) was filled with 100g in the reaction vessel, the water content in the reaction vessel was added water to give 100% saturated steam amount. Then, after the temperature was raised to 650 ° C., and held for 20 minutes to obtain a CHA-type zeolite. Further, the obtained CHA-type zeolite, was evaluated in the same manner as in Example 1. The results are shown in Table 2.
[0056]
[Example 5]
　Precursor (1) was filled with 100g in the reaction vessel, the water content in the reaction vessel was added water to give 100% saturated steam amount. Then, after the temperature was raised to 600 ° C., and held for 20 minutes to obtain a CHA-type zeolite. Further, the obtained CHA-type zeolite, was evaluated in the same manner as in Example 1. The results are shown in Table 2.
[0057]
Example 6
　Precursor (1) was filled with 100g in the reaction vessel, the water content in the reaction vessel was added water to give 100% saturated steam amount. Then, after the temperature was raised to 550 ° C., and held for 20 minutes to obtain a CHA-type zeolite. Further, the obtained CHA-type zeolite, was evaluated in the same manner as in Example 1. The results are shown in Table 2.
[0058]
Example 7
　Precursor (1) was filled with 100g in the reaction vessel, the water content in the reaction vessel was added water to give 100% saturated steam amount. Then, after the temperature was raised to 500 ° C., and held for 20 minutes to obtain a CHA-type zeolite.
[0059]
[Comparative Example 1]
　As a comparative example a precursor (1) was evaluated in the same manner as in Example 1. The results are shown in Table 2.
[0060]
[NH 3 -SCR reaction Evaluation
　zeolite of the present invention as an example of using the catalytic reaction, NH 3 was -SCR reaction evaluation. More specifically, the CHA-type zeolite obtained in Example 6, was supported Cu under the following conditions.
[0061]
　It raised the CHA-type zeolite 10g obtained in suspended 80 ° C. to copper nitrate trihydrate solution 100g of 1 mol / L in Example 6, after 1 hour the ion-exchange with stirring, filtered and washed. This operation is repeated until the amount of supported Cu is 2 mass% to obtain a Cu-CHA-type zeolite. The Cu-CHA-type zeolite by using a conventionally known extruder to obtain a cylindrical shape extruded and molded body (pellet) or granular molded catalyst.
[0062]
　Next, the shaped catalyst body obtained above, NH under the following conditions 3 was -SCR reaction evaluation. The results are shown in Table 3.

reactor atmospheric pressure fixed bed flow reactor
catalyst bodies 10cc
reaction gas NO: 500 ppm, NH 3 : 500 ppm, O 2 : 10%, N 2 : balance
reaction gas flow 6000 cc / min
the reaction temperature of 0.99 ° C., 200 ° C., 300 ° C.

　in each reaction temperature, NO of the reaction tube inlet at the time when the steady state x concentration C in , NO outlet of the reaction tube x concentration C out as it was calculated from the following equation.
NO x removal rate [%] = {(C in -C out ) / C in } × 100
[0063]
[Table 1]

[0064]
[Table 2]

[0065]
[table 3]

The scope of the claims
[Requested item 1]
Following (a), step method for producing a chabazite-type zeolite having a (b).
(A) below (1) (2) Step of preparing a precursor having the structure of (3)
　　　(1) having a chabazite structure
　　　(2) 5 ≦ silica-alumina ratio
　　　(3) 100% ≦ crystallinity
(b) described above the precursor (4) below the step of steam treatment under conditions including a structure of (5)
　　　(4) content of 50% ≦ water
　　　(5) 450 ° C. ≦ treatment temperature ≦ 800 ° C.
[Requested item 2]
　Following (1) to (4) type zeolite having the structure of.
(1) having a chabazite structure
(2) containing Si and Al
(3) lattice constant
13.74A ≦ (4) 140% ≦ crystallinity