CN1108214A - Method No.2 for synthesizing beta zeolite - Google Patents
Method No.2 for synthesizing beta zeolite Download PDFInfo
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- CN1108214A CN1108214A CN 94102213 CN94102213A CN1108214A CN 1108214 A CN1108214 A CN 1108214A CN 94102213 CN94102213 CN 94102213 CN 94102213 A CN94102213 A CN 94102213A CN 1108214 A CN1108214 A CN 1108214A
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Abstract
Silica gel particles of 20-200 mesh as silicon source is put in the solution composed of Al source, NaOH, tetraethylammonium cation and water then mixed uniformly and make the surface of silica gel particle be moistened by the solution. Then the crystallising reaction is undergone for 10-60 hr. under 140-170 deg.C needing no seed crystal. The molar ratios of said reaction system are: SiO2/Al2O3=10-100, Na2O/SiO2=0.01-0.1, TEAOH/SiO2=0.05-1.5, H2O/SiO2=1-3. Advantages are: low consumption of framework agent and water, fast the crystallizing speed, low cost and high yield.
Description
The invention relates to the synthetic method of crystal silicon-aluminate zeolite, specifically, is the synthetic method about the β zeolite.
The β zeolite is (USP3,308,069) that U.S. Mobile company synthesized with classical hydrothermal crystallization method first in 1967.This zeolite has unique three-dimensional (or two dimension) pore passage structure, have very high hydrocracking and hydro-isomerization catalytic activity, behind modification or some metal constituent element of load, can be used for refining of petroleum and petrochemical process such as hydrocracking, hydro-isomerization, hydrofining and Hydrodewaxing, diesel oil pour point depression.According to the disclosed method of this patent, the β zeolite is such synthetic: will contain Na
2O, Al
2O
3, TEAOH(is tetraethyl ammonium hydroxide), SiO
2Make slurries with the mixture of water, 75~200 ℃ of crystallizations are 3~60 days in autoclave.The molar ratio of this reaction system is SiO
2/ Al
2O
3=10~200, Na
2O/TEAOH=0.0~0.1, TEAOH/SiO
2=0.1~1.0, H
2O/TEAOH=20~75.Because the silicon source of adopting in this method is a silicate solutions, water content is big, thereby causes the increase of template tetraethyl ammonium hydroxide consumption.Because therefore the costliness of organic formwork agent price produces β zeolite cost height with this method, is unfavorable for large-scale industrial production.Simultaneously again since entire reaction solution bulky, crystallization time is long, thereby brought the low problem of production efficiency.
Exxon Corporation in 1986 have succeeded in developing a kind of technology (EP187,522) of synthetic β zeolite newly, i.e. " single solution is synthetic " technology.Its concrete grammar is: with SiO
2, Al
2O
3And Na
2Mix with tetraethyl ammonium hydroxide solution again after the solid material of the precursor of O mixes, under 75~150 ℃, the condition that has or do not have the β zeolite seed crystal to exist, carry out crystallization.The molar ratio of this reaction system is SiO
2/ Al
2O
3=10~200, Na
2O/TEA
2O=0.01~0.1, TEA
2O/SiO
2=0.01~0.1, H
2O/TEA
2O=25~150.Because having only tetraethyl ammonium hydroxide in the reaction system is that form with solution adds, and has avoided too much water to introduce system, thereby reduced the consumption of water and tetraethyl ammonium hydroxide in the building-up process, production cost and production efficiency all might be improved.Yet above-mentioned improvement is still not ideal enough, calculates according to the preferred example in this patent, and one ton of β zeolite of every production is 40% tetraethyl ammonium hydroxide solution with regard to the about 1 ton content of need consumption; And adopting the required crystallization time of this synthetic technology to reach 6~10 days, these shortcoming still make the β zeolite be difficult to carry out plant-scale production and application.
Mobile company proposed a kind of improved synthetic β zeolite technology (USP4 again in 1989,875,056), used a kind of silicon source special, that have certain particle size in this technology, this silicon source adds precipitation agent under certain condition by soluble silicon source solution and makes.In synthetic system of zeolite, then use tetraethylammonium bromide to be template, under the situation that crystal seed exists, carried out crystallization.Yet this technology is the problem of unresolved industrial-scale production also also, and this is owing to very easily produce the large usage quantity of mordenite and ZSM-5 stray crystal, tetraethylammonium bromide in the preparation process complexity in this silicon source, crystallization system, has only the TEA of working as
2O/SiO
2>0.14 is TEAOH/SiO
2>0.28 o'clock could reduce the growing amount of stray crystal.
Based on above-mentioned prior art situation, the object of the present invention is to provide a kind of novel synthesis of β zeolite, make the tetraethylammonium cation template agent still less to reduce cost; The consumption of water is still less to improve single-autoclave yield rate; Crystallization time is shorter in to enhance productivity.
Method provided by the invention is that solid-state aluminium source, sodium source are dissolved in the mixed solution of tetraethylammonium cation and water, uses this mixed solution will be wetting as the silica gel particle surface in silicon source then, finishes crystallization then under certain hydrothermal condition.Be enriched in the TEA of silica gel particle surface
+, OH
-Reach other reaction mass at first at silica gel particle surface generation crystallization, crystallization successively is deep into silica gel particle inside then, all is converted into the β zeolite until silica gel particle.
According to wetting crystallizing process for synthesizing provided by the invention, the β zeolite is such synthetic: solid-state aluminium source, sodium hydroxide are dissolved in tetraethyl ammonium hydroxide and the water form working solution, with granularity is that 20~200 purpose silica gel particles are the silicon source, silica gel mixed with working solution make silica gel particle surface wetting by working solution, need not under the condition of plus seed 140~170 ℃ of crystallizations 10~60 hours, isolate solid product, wash, be drying to obtain β zeolite finished product.The mol ratio that each raw material is formed in the reaction system is as follows: SiO
2/ Al
2O
3=10~100, best 10~80, Na
2O/SiO
2=0.01~0.1, TEAOH/SiO
2=0.05~0.15, H
2O/SiO
2=1~3.
Wherein used aluminium source is selected from pseudo-boehmite, SB aluminium hydroxide, aluminium hydroxide.Sodium ion in the used sodium hydroxide can be replaced by other basic metal or alkaline-earth metal ions that does not influence reaction.Used tetraethyl ammonium hydroxide can be replaced by etamon chloride, tetraethylammonium bromide, tetraethyl ammonium iodide and composition thereof.Used silica gel particle is any aperture, comprises the silica gel of gross porosity, mesopore, pore.
Method provided by the invention is that silicon source, working solution only are wetting silica gel particle surface crystallization at once owing to having adopted solid particulate silica gel, thereby has reduced the consumption of the organic formwork agent of reaction system under the identical conditions of mixture ratios, thereby has reduced cost.Only contain very a spot of water owing in the reaction system again, thereby improved output per single reactor greatly.Shortened crystallization time owing to present method simultaneously, thereby for realizing that industrial production β zeolite provides possibility efficiently.
The zeolite that makes with the method for the invention provides has the x-ray diffraction spectra of typical β zeolite, and the d value (nanometer) of its main spectral line is as follows:
1.14±0.02
0.74±0.02
0.67±0.02
0.425±0.01
0.397±0.01
0.30±0.01
0.22±0.01
With the β zeolite that the method for the invention provides makes, its grain size can be carried out modulation by changing reaction conditions, and the variation range of grain size is 0.1~10 micron.
Can also can use through the roasting removed template method after pickling transformation is a Hydrogen with the β zeolite that the invention provides the method preparation with forming Hydrogen through roasting again after the ammonium solution exchange.Can be by ion-exchange, dipping or other method with various metals or its compound, introduce wherein to make it to become the zeolite that contains various different metals as element such as basic metal, alkaline-earth metal, rare earth element, Pt, Pd, Re, Sn, Ni, W, Co or its compound; The compound that also can introduce elements such as different compounds such as P, Ga, Ti, B makes it to become the zeolite with special purpose; Can also make it to have higher silica alumina ratio by the part aluminium that methods such as pickling, chemical extracting are sloughed on the zeolite framework.Can be with present method synthetic β zeolite and modified version thereof as catalyzer, catalyst aid and the sorbent material etc. of multiple refining of petroleum and petrochemical process.
Accompanying drawing 1 and accompanying drawing 2 are to be respectively the x-ray diffraction spectra of the β zeolite that makes of aluminium source with pseudo-boehmite and aluminium hydroxide with method provided by the invention.Spectrogram obtains with CuK α radiation, Ni filtering.
Following example will give further instruction to method provided by the invention.
Comparative example 1~2
According to USP3, the disclosed method of example in 308,069 does not use crystal seed to prepare the β zeolite.
With 2 gram sodium aluminate (Shanghai reagent two factory's product, wherein Al
2O
345%, Na
2O55%) be dissolved in 30 milliliters of tetraethyl ammonium hydroxide solution (Beijing Chemical Plant's product, 2.958N) in, (produce in Beijing the 90, wherein SiO with 81 gram silicon sol again
2Content is 24.7 heavy %) to mix, high degree of agitation is made slurries.The mol ratio of each component is in these slurries: SiO
2/ Al
2O
3=37.8, Na
2O/SiO
2=0.053, TEAOH/SiO
2=0.266, H
2O/SiO
2=13.1.With above-mentioned slurries in reactor 150 ℃ down respectively crystallization take out cooling after two days and three days, after filtration, wash, 110 ℃ be drying to obtain the β zeolite.
With x-ray diffraction method record its relative crystallinity be respectively 60% and this sample of 100%(as standard substance).
Comparative example 3
According to USP3, the disclosed method of example in 308,069 uses crystal seed to prepare the β zeolite.
With 80~120 order silochroms (production of Qingdao silica gel factory), sodium aluminate (Shanghai reagent two factory's product, wherein Al
2O
354%, Na
2O40%) and the β zeolite seed crystal that accounts for system gross weight 0.2% mix, add tetraethyl ammonium hydroxide again and mix.The mol ratio of each component is in this reaction system: SiO
2/ Al
2O
3=62.4, Na
2O/SiO
2=0.04, TEAOH/SiO
2=0.18, H
2O/SiO
2=5.4.Above-mentioned slurries 150 ℃ of following crystallization in reactor are taken out cooling after 6 days, after filtration, the washing, 110 ℃ be drying to obtain the β zeolite.
Recording its relative crystallinity with x-ray diffraction method is 92.0%.
Example 1~5
By method provided by the invention, prepare the β zeolite for the aluminium source with the pseudo-boehmite.(Beijing Chemical Plant produces with industrial pseudo-boehmite (Shandong Aluminum Plant's production), sodium hydroxide, chemical pure) is dissolved in the tetraethyl ammonium hydroxide aqueous solution (Beijing Chemical Plant's product, 2.807N), add or do not add water, silica gel (production of Qingdao silica gel factory) joined in the above-mentioned working solution mix, make silica gel particle surface wetting, under 150 ℃, carry out crystallization by solution, isolate solid product, wash, be drying to obtain the β zeolite.
In each example in various raw material consumptions and the reaction system raw material constitutive molar ratio list in table 1.
The relative crystallinity of each the β zeolite sample that records with x-ray diffraction method also one is listed in table 1.
Prepared each β zeolite sample all has x-ray diffraction spectra as shown in Figure 1.
Table 1
Example | 1 | 2 | 3 | 4 | 5 |
Each raw material consumption pseudo-boehmite, gram sodium hydroxide, gram TEAOH, ml water, milliliter silica gel: weight, the gram particle degree, the order aperture | 1.5 1.5 13.0 4.0 20 80~120 is thick | 1.5 1.5 13.0 4.0 20 80~120 is thick | 1.05 1.5 14.8 0.0 27.3 40~60 is thin | 1.05 1.5 14.8 0.0 27.3 100~200 is thin | 1.05 1.5 14.8 0.0 21.9 40~60 is thick |
The crystallization time, hour | 40 | 60 | 24 | 24 | 29 |
Raw material is formed, mol ratio SiO 2/Al 2O 2Na 2O/SiO 2TEAOH/SiO 2H 2O/SiO 2 | 37.8 0.055 0.109 1.94 | 37.8 0.055 0.109 1.94 | 40 0.057 0.123 2.6 | 40 0.057 0.123 2.8 | 40 0.057 0.123 1.8 |
Relative crystallinity, % | 103.6 | 105.6 | 85.6 | 80.0 | 82.3 |
Example 6~8
By method provided by the invention, be that the aluminium source prepares the β zeolite with SB aluminium hydroxide.
SB aluminium hydroxide (German import), sodium hydroxide are dissolved in the tetraethyl ammonium hydroxide aqueous solution, add certain water gaging again, silica gel joined in the above-mentioned working solution mix, make silica gel particle surface wetting by solution, under 150 ℃, carry out crystallization, isolate solid product, wash, be drying to obtain the β zeolite.
In each example in various raw material consumptions and the reaction system raw material constitutive molar ratio list in table 2.
The relative crystallinity of each the β zeolite sample that records with x-ray diffraction method also one is listed in table 2.
Prepared each β zeolite sample all has x-ray diffraction spectra as shown in Figure 1.
Table 2
Example | 6 | 7 | 8 |
Each raw material consumption SB aluminium hydroxide, gram sodium hydroxide, gram TEAOH, ml water, milliliter silica gel: weight, the gram particle degree, the order aperture | 0.74 0.95 13.2 3.6 20 80~120 is thick | 1.0 1.3 10.8 5.1 20 80~120 is thick | 1.8 1.9 13.2 3.3 20 80~120 is thick |
The crystallization time, |
20 | 35 | 20 |
Raw material is formed, mol ratio SiO 2/Al 2O 2Na 2O/SiO 2TEAOH/SiO 2H 2O/SiO 2 | 62 0.04 0.122 2.2 | 46 0.054 0.100 2.2 | 25 0.079 0.122 2.6 |
Relative crystallinity, % | 102.0 | 95.4 | 94.2 |
Example 9~13
By method provided by the invention, prepare the β zeolite for the aluminium source with the industrial aluminium hydroxide.
Industrial aluminium hydroxide (Shandong Aluminum Plant's production), sodium hydroxide are dissolved in the tetraethyl ammonium hydroxide aqueous solution, add or do not add water, silica gel joined in the above-mentioned working solution mix, make silica gel particle surface wetting by solution, under 150 ℃, carry out crystallization, isolate solid product, wash, be drying to obtain the β zeolite.
In each example in various raw material consumptions and the reaction system raw material constitutive molar ratio list in table 3.
The relative crystallinity of each the β zeolite sample that records with x-ray diffraction method also one is listed in table 3.
Prepared each β zeolite sample all has x-ray diffraction spectra as shown in Figure 2.
Table 3
Example | 1 | 2 | 3 | 4 | 5 |
Each raw material consumption industrial aluminium hydroxide, gram sodium hydroxide, gram TEAOH, ml water, milliliter silica gel: weight, the gram particle degree, the order aperture | 1.4 1.5 13.0 4.0 20 80~120 is thick | 1.4 1.5 13.0 4.0 20 80~120 is thick | 0.9 1.3 13.2 3.7 20 80~120 is thick | 1.5 1.5 14.8 0.0 27.3 40~60 is thin | 1.5 1.5 14.8 0.0 27.2 100~200 is thin |
The crystallization time, hour | 35 | 60 | 29 | 24 | 24 |
Raw material is formed, mol ratio SiO 2/Al 2O 2Na 2O/SiO 2TEAOH/SiO 2H 2O/SiO 2 | 37.8 0.055 0.109 1.94 | 37.8 0.055 0.109 1.94 | 60.0 0.054 0.123 2.6 | 35.0 0.055 0.138 1.8 | 35.0 0.055 0.138 1.8 |
Relative crystallinity, % | 100.6 | 103.9 | 100.0 | 86.6 | 80.6 |
Example 14~16
By method provided by the invention, be that the aluminium source prepares the β zeolite with reagent aluminium hydroxide.
(chemical reagent two factories in Beijing produce, and contain 57.0%Al with reagent aluminium hydroxide
2O
3), sodium hydroxide is dissolved in the tetraethyl ammonium hydroxide aqueous solution, adds a certain amount of water, silica gel is joined in the above-mentioned working solution mix, make silica gel particle surface wetting by solution, under 150 ℃, carry out crystallization, isolate solid product, wash, be drying to obtain the β zeolite.
In each example in various raw material consumptions and the reaction system raw material constitutive molar ratio list in table 4.
The relative crystallinity of each the β zeolite sample that records with x-ray diffraction method also one is listed in table 4.
Prepared each β zeolite sample all has x-ray diffraction spectra as shown in Figure 2.
Table 4
Example | 14 | 15 | 16 |
Each raw material consumption reagent aluminium hydroxide, gram sodium hydroxide, gram TEAOH, ml water, milliliter silica gel: weight, the gram particle degree, the order aperture | 1.1 0.95 13.2 3.4 20.0 80~120 is thick | 2.1 1.3 10.8 4.8 20.0 80~120 is thick | 2.1 1.9 13.2 3.3 20.0 80~120 is thick |
The crystallization time, |
20 | 40 | 20 |
Raw material is formed, mol ratio SiO 2/Al 2O 2Na 2O/SiO 2TEAOH/SiO 2H 2O/SiO 2 | 62.0 0.04 0.122 2.2 | 25.0 0.048 0.09 2.0 | 25.0 0.071 0.11 2.0 |
Relative crystallinity, % | 102.3 | 100.0 | 96.8 |
Claims (6)
1, a kind of method of synthetic β zeolite, it is characterized in that making silica gel particle surface wetting by the reaction working solution of forming by aluminium source, sodium hydroxide, tetraethyl ammonium hydroxide, water, in 140~170 ℃ of following crystallizations 10~60 hours, this reaction system had following mol ratio and forms: SiO
2/ Al
2O
3=10~100, Na
2O/SiO
2=0.01~0.1, TEAOH/SiO
2=0.05~0.15, H
2O/SiO
2=1~3.
2, in accordance with the method for claim 1, it is characterized in that said silica gel particle is any aperture and has 20~200 purpose granularities.
3, in accordance with the method for claim 1, it is characterized in that said aluminium source is selected from pseudo-boehmite, SB aluminium hydroxide, aluminium hydroxide.
4, in accordance with the method for claim 1, it is characterized in that the sodium ion in the said sodium hydroxide can be replaced by other basic metal or alkaline-earth metal ions that does not influence reaction.
5, in accordance with the method for claim 1, it is characterized in that said tetraethyl ammonium hydroxide can be replaced by etamon chloride, tetraethylammonium bromide, tetraethyl ammonium iodide and composition thereof.
6, in accordance with the method for claim 1, it is characterized in that SiO in the said reaction system
2/ Al
2O
3=10~80.
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CN1041616C CN1041616C (en) | 1999-01-13 |
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Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN1051055C (en) * | 1996-01-11 | 2000-04-05 | 中国石油化工总公司 | Method for synthesis of beta-zeolite |
CN1123535C (en) * | 1998-11-18 | 2003-10-08 | 中国石油化工集团公司 | Preparation process of beta-zeolite |
CN104649296A (en) * | 2013-11-19 | 2015-05-27 | 中国石油天然气股份有限公司 | Preparation method of H beta molecular sieve capable of improving silicon-aluminum ratio |
RU2737895C1 (en) * | 2020-05-12 | 2020-12-04 | Общество С Ограниченной Ответственностью "Цеолитика" | Method of producing nanocrystalline zeolite bea (versions) and obtained zeolite bea (versions) |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE69417942T2 (en) * | 1993-02-02 | 1999-08-26 | Tosoh Corp. | Method of making beta zeolite |
DE4306226A1 (en) * | 1993-02-27 | 1994-09-01 | Abb Patent Gmbh | Arc extinguishing arrangement, in particular for a circuit breaker and contactors |
KR970011464B1 (en) * | 1993-03-12 | 1997-07-11 | 주식회사 유공 | Polypropylene resin component |
-
1994
- 1994-03-11 CN CN94102213A patent/CN1041616C/en not_active Expired - Lifetime
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN1051055C (en) * | 1996-01-11 | 2000-04-05 | 中国石油化工总公司 | Method for synthesis of beta-zeolite |
CN1123535C (en) * | 1998-11-18 | 2003-10-08 | 中国石油化工集团公司 | Preparation process of beta-zeolite |
CN104649296A (en) * | 2013-11-19 | 2015-05-27 | 中国石油天然气股份有限公司 | Preparation method of H beta molecular sieve capable of improving silicon-aluminum ratio |
RU2737895C1 (en) * | 2020-05-12 | 2020-12-04 | Общество С Ограниченной Ответственностью "Цеолитика" | Method of producing nanocrystalline zeolite bea (versions) and obtained zeolite bea (versions) |
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