CN1073968C - Process for preparing fine-grain octahedra zeolite - Google Patents
Process for preparing fine-grain octahedra zeolite Download PDFInfo
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- CN1073968C CN1073968C CN98101495A CN98101495A CN1073968C CN 1073968 C CN1073968 C CN 1073968C CN 98101495 A CN98101495 A CN 98101495A CN 98101495 A CN98101495 A CN 98101495A CN 1073968 C CN1073968 C CN 1073968C
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- reaction mixture
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- sio
- molecular sieve
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Abstract
The present invention provides a method for preparing a fine crystal grain Y type zeolite. A reaction mixture used for synthesizing the Y type zeolite is prepared from a faujasite guiding agent, a silicon source, an aluminum source, water and acids or alkali with a the prior art method; the reaction mixture is hydrothermally crystallized on the conventional conditions. The method is characterized in that the reaction mixture contains rare earth ions, and the quantity of the rare earth ions is 0.005 to 0.5 time of the mole number of Al2O3 in the reaction mixture. The average crystal grain size of the Y type molecular sieve synthesized with the method of the present invention is smaller than 300 nanometers, and under the preferable condintions, the average crystal grain size of the Y type molecular sieve is smaller than 100 nanometers; the framework silica alumina ratio of products is generally larger than 5.0, and the crystallinity degree is generally more than 80%.
Description
The invention relates to a kind of fine-grain octahedra zeolite, particularly the synthetic method of Y type faujusite.
As everyone knows, the main application of molecular sieve in commercial run is two aspects: catalysis and selective adsorption substantially.In these processes, be adsorbed molecule and pass the hole of molecular sieve crystal and the diffusion size of cage, show importantly, be conclusive effect sometimes.For reactant shape selective catalysis aspect, have only when the reactant molecule size less than the molecular sieve aperture and overcome molecular sieve crystal surface energy barrier, just can diffuse in the molecular sieve pore passage, specific catalyzed reaction takes place.And those sizes are greater than the conversion of reactant molecule on catalyzer in molecular sieve aperture, then can only depend on the active sites on the molecular sieve crystal outside surface, at this moment the size of molecular sieve outer surface and reactant molecule diffusion on the outer surface then seems even more important, the size of zeolite crystal plays an important role, compare with big crystal grain, little or even molecular sieve ultra micro has more outer surface area, and better therefore diffusion more helps the generation of said process.
Because active higher, molecular sieve generally is to be dispersed in than in the inert matrix, as silica gel, aluminum oxide or alumino silica gel, uses with the compound state form.But the zeolite crystal degree of ordinary method preparation is bigger, be unfavorable for homodisperse in matrix, caused the fluctuation of each position molecular sieve excessive concentration in the matrix, only there are some active centre few in number in the catalyzer, reduce its service efficiency (molecular sieve fails to contact fully with reactant molecule and the product molecule can not be left away fast), and shortened life of catalyst (easily coking and deactivation).And if use little or even molecular sieve ultra micro, will overcome above-mentioned drawback.In addition, heaviness and poor qualityization along with refinery feedstock require catalyzer to have higher anti-sulphur, anti-nitrogen and preventing from heavy metal ability.For the macrobead molecular sieve, can disperse more ultramicron molecular sieve in the catalyzer, therefore, for the pollution of sulphur, nitrogen and heavy metal etc., the catalyzer that contains the ultra micro molecular sieve will have more remaining activity, thereby have the higher life-span.
There are some hydrocarbon processing processes to use the metal catalyst of molecular sieve and supported carrier, for example hydrocracking, hydroisomerizing, reformation etc.Useful load amount and the dispersing property of metal component on carrier is the principal element of this class catalyst catalytic performance of decision.The useful load amount of metal component is high more, and dispersing property is good more, and then the efficient of catalyzer is high more.Usually, on big zeolite crystal, the content of metal component has a limit, surpasses this limit, and metal component then is present in the surface or is piled up in the aperture with the agglomerate form, has reduced activity of such catalysts and selectivity.And on the ultra micro molecular sieve, the dispersity of metal component and effective content all are improved, thereby can increase activity of such catalysts, selectivity and keep longer catalyst life.
The faujusite grain size has report for catalytic cracking reaction performance and optionally influence in the document.K.Rajagopalan, people such as A.W.Peters and G.C.Edwards [Applied Catalysis, 23 (1986) 69～80 pages] to have reported in grain fineness number be on the Y zeolite of 50 nanometers, has higher activity and better choice for the cracking of heavy gas oil.
There are some patent documentations once the method that reduces the zeolite crystal degree to be reported.In US3864282 and US3528615, described with behind the hot crushing technology processing faujusite, can make grain fineness number be decreased to 100 nanometers.US4587115 and EP0435625A2 report is higher than 3000 rev/mins high shear force to synthetic system and stirs before crystallization, the prepared faujusite grain fineness number that goes out is 100～50 nanometers.The preparation method that US3755538 reported adds a small amount of B in alumino silica gel, V, and P, Mo, W, Ge or Ga element, the faujusite that is synthesized has the grain fineness number of 200～600 nanometers.
Changing the liquid phase synthesis condition also is one of effective way that reduces the zeolite crystal degree.Synthesis condition is generally high basicity, high silica alumina ratio, dilute solution and lower temperature.By in synthetic system, introducing the organic solvent that can dissolve each other with water, also can reduce the grain fineness number of the faujusite that synthesized effectively.The US3516786 report, before synthetic system intensification crystallization steps, to synthetic system add on a small quantity can be miscible with water organic solvent, as: methyl alcohol, ethanol, dimethyl sulfone, N, dinethylformamide, tetrahydrofuran (THF), acetone etc., the faujusite that synthesizes has the grain fineness number of 10～100 nanometers.And in US4372931,, synthesized faujusite with 40～60 nanocrystalline granularities then by adding monose or polysaccharide.But add the molecular sieve that synthesizes behind organic solvent or the carbohydrate and generally have lower framework si-al ratio, generally be lower than 2.5, that is to say and can not synthesize Y zeolite and can only synthesize X type molecular sieve, and organic solvent is easy to volatilization under the hydrothermal crystallizing condition.
The synthetic method that the purpose of this invention is to provide a kind of close grain y-type zeolite makes the y-type zeolite that is synthesized have average crystal grain size less than 300 nanometers, also has higher framework si-al ratio and higher degree of crystallinity simultaneously.
The synthetic method of y-type zeolite provided by the present invention is a kind of faujusite directed agents, silicon source, aluminium source, water and acid or alkali to be prepared into a kind of mole according to the method for prior art consist of SiO
2/ Al
2O
3=8～30, Na
2O/SiO
2=0.2～0.6, H
2O/Na
2O=25～80, preferred group becomes SiO
2/ Al
2O
3=8～15, Na
2O/SiO
2=0.3～0.5, H
2O/Na
2The reaction mixture of O=35～50, condition hydrothermal crystallizing routinely is characterized in that containing rare earth ion in the said reaction mixture then, and the amount of this rare earth ion (mole number) is Al in the said reaction mixture
2O
30.005～0.5 times of mole number, preferred 0.01～0.4 times.Na wherein
2O represents the basicity of mixture.
Said reaction mixture preferably mixes various raw materials and prepares in the method provided by the present invention under 0～10 ℃ temperature, can further reduce the grain size of gained molecular sieve like this.
Said faujusite directed agents is an existing faujusite directed agents in the prior art in the method provided by the present invention, and its mole composition is generally (11～18) Na
2O: Al
2O
3: (10～17) SiO
2: (100～350) H
2O, this directed agents can prepare by the whole bag of tricks of preparation faujusite directed agents in the prior art, for example according to USP3,639,099, USP3,671,191, USP4,166,099, the method for preparing directed agents that is proposed among CN85102733A and the CN1081425A prepares.Contained Al in this directed agents
2O
3Mole number should be Al in the said reaction mixture
2O
3Total mole number 1～30%, preferred 5～20%.
Said silicon source preferably water glass or silicon sol in the method provided by the present invention, said aluminium source is Tai-Ace S 150 preferably.
Said rare earth element is at least a or two or more mixture in them in the elements such as La, Ce, Nb, Pr, Sm, Gd in the method provided by the present invention, or from the prepared lucium of rare-earth mineral.
Said hydrothermal crystallizing condition generally is a crystallization 6～60 hours under 80～120 ℃ temperature in the method provided by the present invention, preferably crystallization 10～48 hours under 90～110 ℃ temperature.
In the method provided by the present invention owing in synthesis reaction mixture, added rare earth ion, this rare earth ion can promote the nucleation and the crystalline growth of molecular sieve, thereby the grain fineness number of gained molecular sieve is obviously reduced, and the framework si-al ratio of product and degree of crystallinity do not reduce.The Y zeolite that synthesizes according to method provided by the present invention generally has the mean grain size less than 300 nanometers, can have mean grain size in the preferred case less than 100 nanometers, the framework si-al ratio of product is generally greater than 5.0, and degree of crystallinity is generally more than 80%.
Fig. 1 is transmission electron microscope (TEM) photo (magnification is 27K) of embodiment 3 products obtained therefrom molecular sieves.
The following examples will the present invention is described further.In each embodiment and Comparative Examples, the mean grain size of gained zeolite product is measured with transmission electron microscopy (TEM), specific surface area is measured with CNS GB/T5816-1995 method, relative crystallinity (is seen " petrochemical complex analytical procedure " according to the RIPP146-90 standard method, Yang Cui waits volume surely, Science Press, nineteen ninety publishes) measure framework si-al ratio (SiO
2/ Al
2O
3) measuring method be the unit cell parameters a that determines earlier molecular sieve according to RIPP145-90 standard method (the same)
0, then according to formula S iO
2/ Al
2O
3=(25.248-a
0) * 2 ÷ 0.245 calculates.
Embodiment 1
The preparation of the faujusite directed agents that present embodiment explanation the present invention is used.
With 45.1 gram Tai-Ace S 150 (Al
2(SO
4)
318H
2O, the analytical pure commercial reagent, down with), (Changhong chemical plant, Beijing produces 235.2 gram silicon sol, contains 25.9 heavy %SiO
2With 0.2 heavy %Na
2O, down with), 105.9 gram sodium hydroxide (analytical pure commercial reagent, down with) and 189.8 gram deionized waters, under room temperature (25 ℃) and stirring condition, mix, at room temperature still aging then 24 hours, the reaction mixture that obtains was as directed agents.
Comparative Examples 1
This Comparative Examples illustrates the preparation of conventional y-type zeolite.
Under room temperature and stirring condition, with 26.65 gram sodium hydroxide, 148.2 gram silicon sol, 45.1 gram Tai-Ace S 150,38.0 gram deionized waters, and the directed agents that makes among the embodiment 1 of 64.0 grams mix mutually, continue to stir more than 0.5 hour fast, then the gained mixture is packed in the stainless steel sealed reactor, 90 ℃ of following hydrothermal crystallizings 48 hours.Product after the crystallization after filtration and be washed with water to filtrate PH＜10, the gained filtering medium is 100 ℃ of oven dry down.X-ray diffraction (XRD) analysis revealed products therefrom is a Y zeolite, SiO
2/ Al
2O
3=5.11, relative crystallinity is 90%.Tem analysis shows that the mean grain size of products molecule sieve is 850 nanometers.It is 750m that the BET method records its specific surface area
2/ g.
Embodiment 2
Under room temperature (25 ℃) and stirring condition, with 28.5 gram sodium hydroxide, 148.1 gram silicon sol, 45.1 gram Tai-Ace S 150,37.1 gram deionized waters, and the directed agents that makes among the embodiment 1 of 64.0 grams mix, add 3.8 gram rare earth chloride mixture (Baotou rare earth company products then, wherein the weight percent in oxide compound consists of: 46%Ce, 26%La, 17%Nb, 6%Pr, 3%Sm and 2%Gd, down together), continue to stir 0.5 hour.Then the gained mixture is packed in the stainless steel sealed reactor, 100 ℃ of following hydrothermal crystallizings 24 hours.Product after the crystallization after filtration and be washed with water to filtrate PH＜10, the gained filtering medium is 100 ℃ of oven dry down.X-ray diffraction (XRD) analysis revealed products therefrom is Y zeolite (XRD diffraction peak position and intensity see Table 1), SiO
2/ Al
2O
3=5.55, relative crystallinity is 85%.Tem analysis shows that the mean grain size of products molecule sieve is 110 nanometers.It is 760m that the BET method records its specific surface area
2/ g.
Table 1
| 2θ | h 2+k 2+l 2 | d | I/I 0 |
| 6.22 10.17 11.94 15.71 18.75 20.43 22.87 23.74 25.87 27.14 27.87 29.73 30.85 31.51 32.57 33.19 34.21 34.8 38.03 | 3 8 11 19 27 32 40 43 51 56 59 67 72 75 80 83 88 91 108 | 14.19 8.688 7.407 5.635 4.729 4.344 3.885 3.747 3.441 3.283 3.199 3.002 2.896 2.837 2.747 2.697 2.619 2.576 2.364 | 100 15 24 41 23 35 13 47 9 37 8 14 20 48 21 7 19 11 13 |
Embodiment 3
Under 0 ℃ and stirring condition, with 30.5 gram sodium hydroxide, 166.7 gram silicon sol, 50.7 gram Tai-Ace S 150,42.7 gram deionized waters, and the directed agents that makes among the embodiment 1 of 72.0 grams mix, add 1.1 gram rare earth chlorides then, continue to stir 0.5 hour.Then the gained mixture is packed in the stainless steel sealed reactor, 90 ℃ of following hydrothermal crystallizings 24 hours.Product after the crystallization after filtration and be washed with water to filtrate PH＜10, the gained filtering medium is 100 ℃ of oven dry down.X-ray diffraction (XRD) analysis revealed products therefrom is Y zeolite (XRD diffraction peak position and intensity and table 1 is basic identical), SiO
2/ Al
2O
3=5.83, relative crystallinity is 80%.Tem analysis shows that the mean grain size of products molecule sieve is 70 nanometers.It is 755m that the BET method records its specific surface area
2/ g.
Embodiment 4
Under 10 ℃ and stirring condition, with 27.6 gram sodium hydroxide, 148.1 gram silicon sol, 45.1 gram Tai-Ace S 150,37.1 gram deionized waters, and the directed agents that makes among the embodiment 1 of 64.0 grams mix, add 1.9 gram rare earth chlorides then, continue to stir 0.5 hour.Then the gained mixture is packed in the stainless steel sealed reactor, 90 ℃ of following hydrothermal crystallizings 24 hours.Product after the crystallization after filtration and be washed with water to filtrate PH＜10, the gained filtering medium is 100 ℃ of oven dry down.X-ray diffraction (XRD) analysis revealed products therefrom is Y zeolite (XRD diffraction peak position and intensity and table 1 is basic identical), SiO
2/ Al
2O
3=5.76, relative crystallinity is 85%.Tem analysis shows that the mean grain size of products molecule sieve is 90 nanometers.It is 762m that the BET method records its specific surface area
2/ g.
Embodiment 5
Under 0 ℃ and stirring condition, with 26.8 gram sodium hydroxide, 148.1 gram silicon sol, 45.1 gram Tai-Ace S 150,37.8 gram deionized waters, and the directed agents that makes among the embodiment 1 of 64.0 grams mix, add 0.3 gram rare earth chloride then, continue to stir 0.5 hour.Then the gained mixture is packed in the stainless steel sealed reactor, 90 ℃ of following hydrothermal crystallizings 20 hours.Product after the crystallization after filtration and be washed with water to filtrate PH＜10, the gained filtering medium is 100 ℃ of oven dry down.X-ray diffraction (XRD) analysis revealed products therefrom is Y zeolite (XRD diffraction peak position and intensity and table 1 is basic identical), SiO
2/ Al
2O
3=5.69, relative crystallinity is 86%.Tem analysis shows that the mean grain size of products molecule sieve is 80 nanometers.It is 770m that the BET method records its specific surface area
2/ g.
Embodiment 6
Under room temperature (25 ℃) and stirring condition, with 32.8 gram sodium hydroxide, 205.9 gram silicon sol, 50.7 gram Tai-Ace S 150,38.3 gram deionized waters, and the directed agents that makes among the embodiment 1 of 72.0 grams mix, add 4.3 gram rare earth chlorides then, continue to stir 0.5 hour.Then the gained mixture is packed in the stainless steel sealed reactor, 100 ℃ of following hydrothermal crystallizings 20 hours.Product after the crystallization after filtration and be washed with water to filtrate PH＜10, the gained filtering medium is 100 ℃ of oven dry down.X-ray diffraction (XRD) analysis revealed products therefrom is Y zeolite (XRD diffraction peak position and intensity and table 1 is basic identical), SiO
2/ Al
2O
3=5.75, relative crystallinity is 90%.Tem analysis shows that the mean grain size of products molecule sieve is 100 nanometers.It is 770m that the BET method records its specific surface area
2/ g.
Claims (9)
1. the synthetic method of a y-type zeolite comprises that a kind of faujusite directed agents, silicon source, aluminium source, water and acid or alkali are prepared into a kind of mole consists of SiO
2/ Al
2O
3=8～30, Na
2O/SiO
2=0.2～0.6, H
2O/Na
2The reaction mixture of O=25～80, condition hydrothermal crystallizing routinely is characterized in that containing rare earth ion in the said reaction mixture then, and the consumption of this rare earth ion is Al in the said reaction mixture
2O
30.005～0.5 times of mole number.
2. according to the method for claim 1, it is characterized in that said reaction mixture is that said various raw materials are mixed and prepare under 0～10 ℃ temperature.
3. according to the process of claim 1 wherein that said faujusite directed agents consists of (11～18) Na for its mole
2O: Al
2O
3: (10～17) SiO
2: (100～350) H
2O, contained Al in this directed agents
2O
3Mole number be Al in the said reaction mixture
2O
3Total mole number 5～20%.
4. according to the process of claim 1 wherein that said silicon source is water glass or silicon sol, said aluminium source is a Tai-Ace S 150.
5. according to the process of claim 1 wherein that said rare earth metal is to be selected from least a among La, Ce, Nb, Pr, Sm, the Gd or the two or more mixture in them, or from the prepared lucium of rare-earth mineral.
6. according to the method for claim 5, wherein said rare earth metal is from the prepared lucium of rare-earth mineral.
7. according to the process of claim 1 wherein that the mole of said reaction mixture consists of: SiO
2/ Al
2O
3=8～15, Na
2O/SiO
2=0.3～0.5, H
2O/Na
2O=35～50, rare earth ion/Al
2O
3=0.01～0.4.
8. according to the process of claim 1 wherein that said hydrothermal crystallizing condition is a crystallization 6～60 hours under 80～120 ℃ temperature.
9. according to the method for claim 8, wherein said hydrothermal crystallizing condition is a crystallization 10～48 hours under 90～110 ℃ temperature.
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|---|---|---|---|
| CN98101495A CN1073968C (en) | 1998-06-04 | 1998-06-04 | Process for preparing fine-grain octahedra zeolite |
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|---|---|---|---|
| CN98101495A CN1073968C (en) | 1998-06-04 | 1998-06-04 | Process for preparing fine-grain octahedra zeolite |
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| Publication Number | Publication Date |
|---|---|
| CN1238306A CN1238306A (en) | 1999-12-15 |
| CN1073968C true CN1073968C (en) | 2001-10-31 |
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Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1133585C (en) * | 2000-12-20 | 2004-01-07 | 太原理工大学 | Process for preparing nm zeolite |
| CN100544822C (en) * | 2006-09-15 | 2009-09-30 | 杨加炎 | The preparation method of catalyst and cracking of hydrocarbon and institute's Y-shaped molecular sieve containing rare earth |
| CN110562995B (en) * | 2018-06-06 | 2021-05-28 | 中国石油化工股份有限公司 | Synthesis method of nano Y zeolite, synthesized nano Y zeolite and application |
| WO2022148394A1 (en) * | 2021-01-07 | 2022-07-14 | 中国石油化工股份有限公司 | Y-type molecular sieve and synthesis method therefor |
| CN116119680B (en) * | 2023-01-17 | 2024-09-24 | 西南科技大学 | Method for solidifying nonferrous metal tailings by using 4A zeolite and solidified body thereof |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4372931A (en) * | 1980-05-30 | 1983-02-08 | Air Products And Chemicals, Inc. | Microcrystalline synthetic faujasite |
| CN1160676A (en) * | 1996-03-21 | 1997-10-01 | 中国石油化工总公司 | Preparation process of fine-grain NaY zeolite |
-
1998
- 1998-06-04 CN CN98101495A patent/CN1073968C/en not_active Expired - Lifetime
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4372931A (en) * | 1980-05-30 | 1983-02-08 | Air Products And Chemicals, Inc. | Microcrystalline synthetic faujasite |
| CN1160676A (en) * | 1996-03-21 | 1997-10-01 | 中国石油化工总公司 | Preparation process of fine-grain NaY zeolite |
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|---|---|
| CN1238306A (en) | 1999-12-15 |
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