CN101468803B - Method for synthesizing fine grain NaY molecular sieve - Google Patents
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- 238000000034 method Methods 0.000 title claims abstract description 53
- 239000002808 molecular sieve Substances 0.000 title claims abstract description 46
- URGAHOPLAPQHLN-UHFFFAOYSA-N sodium aluminosilicate Chemical compound [Na+].[Al+3].[O-][Si]([O-])=O.[O-][Si]([O-])=O URGAHOPLAPQHLN-UHFFFAOYSA-N 0.000 title claims abstract description 46
- 230000002194 synthesizing effect Effects 0.000 title abstract description 10
- 239000003795 chemical substances by application Substances 0.000 claims abstract description 50
- 238000002425 crystallisation Methods 0.000 claims abstract description 45
- 230000008025 crystallization Effects 0.000 claims abstract description 44
- 239000000654 additive Substances 0.000 claims abstract description 22
- 230000000996 additive effect Effects 0.000 claims abstract description 22
- 238000010189 synthetic method Methods 0.000 claims abstract description 13
- 229920001542 oligosaccharide Polymers 0.000 claims abstract description 12
- 150000002482 oligosaccharides Chemical class 0.000 claims abstract description 12
- 229920002101 Chitin Polymers 0.000 claims abstract description 11
- PNEYBMLMFCGWSK-UHFFFAOYSA-N Alumina Chemical compound [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 29
- 229910004298 SiO 2 Inorganic materials 0.000 claims description 25
- 238000011084 recovery Methods 0.000 claims description 4
- 235000010469 Glycine max Nutrition 0.000 claims description 3
- 244000068988 Glycine max Species 0.000 claims description 3
- RQFQJYYMBWVMQG-IXDPLRRUSA-N chitotriose Chemical group O[C@@H]1[C@@H](N)[C@H](O)O[C@H](CO)[C@H]1O[C@H]1[C@H](N)[C@@H](O)[C@H](O[C@H]2[C@@H]([C@@H](O)[C@H](O)[C@@H](CO)O2)N)[C@@H](CO)O1 RQFQJYYMBWVMQG-IXDPLRRUSA-N 0.000 claims description 3
- PVXPPJIGRGXGCY-DJHAAKORSA-N 6-O-alpha-D-glucopyranosyl-alpha-D-fructofuranose Chemical compound O[C@@H]1[C@@H](O)[C@H](O)[C@@H](CO)O[C@@H]1OC[C@@H]1[C@@H](O)[C@H](O)[C@](O)(CO)O1 PVXPPJIGRGXGCY-DJHAAKORSA-N 0.000 claims description 2
- GUBGYTABKSRVRQ-QKKXKWKRSA-N Lactose Natural products OC[C@H]1O[C@@H](O[C@H]2[C@H](O)[C@@H](O)C(O)O[C@@H]2CO)[C@H](O)[C@@H](O)[C@H]1O GUBGYTABKSRVRQ-QKKXKWKRSA-N 0.000 claims description 2
- MUPFEKGTMRGPLJ-RMMQSMQOSA-N Raffinose Natural products O(C[C@H]1[C@@H](O)[C@H](O)[C@@H](O)[C@@H](O[C@@]2(CO)[C@H](O)[C@@H](O)[C@@H](CO)O2)O1)[C@@H]1[C@H](O)[C@@H](O)[C@@H](O)[C@@H](CO)O1 MUPFEKGTMRGPLJ-RMMQSMQOSA-N 0.000 claims description 2
- UQZIYBXSHAGNOE-USOSMYMVSA-N Stachyose Natural products O(C[C@H]1[C@@H](O)[C@H](O)[C@H](O)[C@@H](O[C@@]2(CO)[C@H](O)[C@@H](O)[C@@H](CO)O2)O1)[C@@H]1[C@H](O)[C@@H](O)[C@@H](O)[C@H](CO[C@@H]2[C@@H](O)[C@@H](O)[C@@H](O)[C@H](CO)O2)O1 UQZIYBXSHAGNOE-USOSMYMVSA-N 0.000 claims description 2
- MUPFEKGTMRGPLJ-UHFFFAOYSA-N UNPD196149 Natural products OC1C(O)C(CO)OC1(CO)OC1C(O)C(O)C(O)C(COC2C(C(O)C(O)C(CO)O2)O)O1 MUPFEKGTMRGPLJ-UHFFFAOYSA-N 0.000 claims description 2
- 210000000232 gallbladder Anatomy 0.000 claims description 2
- 239000008101 lactose Substances 0.000 claims description 2
- -1 oligoisomaltose Chemical compound 0.000 claims description 2
- MUPFEKGTMRGPLJ-ZQSKZDJDSA-N raffinose Chemical compound O[C@H]1[C@H](O)[C@@H](CO)O[C@@]1(CO)O[C@@H]1[C@H](O)[C@@H](O)[C@H](O)[C@@H](CO[C@@H]2[C@@H]([C@@H](O)[C@@H](O)[C@@H](CO)O2)O)O1 MUPFEKGTMRGPLJ-ZQSKZDJDSA-N 0.000 claims description 2
- UQZIYBXSHAGNOE-XNSRJBNMSA-N stachyose Chemical compound O[C@H]1[C@H](O)[C@@H](CO)O[C@@]1(CO)O[C@@H]1[C@H](O)[C@@H](O)[C@H](O)[C@@H](CO[C@@H]2[C@@H]([C@@H](O)[C@@H](O)[C@@H](CO[C@@H]3[C@@H]([C@@H](O)[C@@H](O)[C@@H](CO)O3)O)O2)O)O1 UQZIYBXSHAGNOE-XNSRJBNMSA-N 0.000 claims description 2
- GUBGYTABKSRVRQ-XLOQQCSPSA-N Alpha-Lactose Chemical compound O[C@@H]1[C@@H](O)[C@@H](O)[C@@H](CO)O[C@H]1O[C@@H]1[C@@H](CO)O[C@H](O)[C@H](O)[C@H]1O GUBGYTABKSRVRQ-XLOQQCSPSA-N 0.000 claims 1
- 235000021255 galacto-oligosaccharides Nutrition 0.000 claims 1
- 150000003271 galactooligosaccharides Chemical class 0.000 claims 1
- 229910018072 Al 2 O 3 Inorganic materials 0.000 abstract 1
- CSDREXVUYHZDNP-UHFFFAOYSA-N alumanylidynesilicon Chemical compound [Al].[Si] CSDREXVUYHZDNP-UHFFFAOYSA-N 0.000 abstract 1
- 238000001879 gelation Methods 0.000 abstract 1
- 239000000047 product Substances 0.000 description 30
- 239000000126 substance Substances 0.000 description 30
- 239000003054 catalyst Substances 0.000 description 29
- 239000000243 solution Substances 0.000 description 29
- 241000196324 Embryophyta Species 0.000 description 28
- 238000007670 refining Methods 0.000 description 28
- 239000011734 sodium Substances 0.000 description 28
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 description 21
- 235000019353 potassium silicate Nutrition 0.000 description 16
- ANBBXQWFNXMHLD-UHFFFAOYSA-N aluminum;sodium;oxygen(2-) Chemical compound [O-2].[O-2].[Na+].[Al+3] ANBBXQWFNXMHLD-UHFFFAOYSA-N 0.000 description 14
- 229910001388 sodium aluminate Inorganic materials 0.000 description 14
- 239000013078 crystal Substances 0.000 description 11
- 238000003756 stirring Methods 0.000 description 11
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 10
- 239000000203 mixture Substances 0.000 description 10
- 239000010457 zeolite Substances 0.000 description 10
- 229910021536 Zeolite Inorganic materials 0.000 description 9
- DIZPMCHEQGEION-UHFFFAOYSA-H aluminium sulfate (anhydrous) Chemical compound [Al+3].[Al+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O DIZPMCHEQGEION-UHFFFAOYSA-H 0.000 description 9
- HNPSIPDUKPIQMN-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Al]O[Al]=O HNPSIPDUKPIQMN-UHFFFAOYSA-N 0.000 description 9
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 9
- 238000013019 agitation Methods 0.000 description 8
- 239000008367 deionised water Substances 0.000 description 8
- 229910021641 deionized water Inorganic materials 0.000 description 8
- 239000013081 microcrystal Substances 0.000 description 8
- 238000002441 X-ray diffraction Methods 0.000 description 7
- 238000002156 mixing Methods 0.000 description 7
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 6
- 238000002360 preparation method Methods 0.000 description 6
- 229910052708 sodium Inorganic materials 0.000 description 6
- 239000004115 Sodium Silicate Substances 0.000 description 5
- 239000002253 acid Substances 0.000 description 5
- 230000032683 aging Effects 0.000 description 5
- 239000000377 silicon dioxide Substances 0.000 description 5
- 229910052911 sodium silicate Inorganic materials 0.000 description 5
- 230000015572 biosynthetic process Effects 0.000 description 4
- 239000002245 particle Substances 0.000 description 4
- 238000003786 synthesis reaction Methods 0.000 description 4
- 239000003513 alkali Substances 0.000 description 3
- 239000003153 chemical reaction reagent Substances 0.000 description 3
- 238000007796 conventional method Methods 0.000 description 3
- 238000002834 transmittance Methods 0.000 description 3
- PEDCQBHIVMGVHV-UHFFFAOYSA-N Glycerine Chemical compound OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 2
- 229920002472 Starch Polymers 0.000 description 2
- LPQOADBMXVRBNX-UHFFFAOYSA-N ac1ldcw0 Chemical compound Cl.C1CN(C)CCN1C1=C(F)C=C2C(=O)C(C(O)=O)=CN3CCSC1=C32 LPQOADBMXVRBNX-UHFFFAOYSA-N 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- 239000004411 aluminium Substances 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 238000009792 diffusion process Methods 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- 239000003292 glue Substances 0.000 description 2
- 230000007062 hydrolysis Effects 0.000 description 2
- 238000006460 hydrolysis reaction Methods 0.000 description 2
- 229910052710 silicon Inorganic materials 0.000 description 2
- 239000010703 silicon Substances 0.000 description 2
- PUZPDOWCWNUUKD-UHFFFAOYSA-M sodium fluoride Chemical compound [F-].[Na+] PUZPDOWCWNUUKD-UHFFFAOYSA-M 0.000 description 2
- 239000008107 starch Substances 0.000 description 2
- 235000019698 starch Nutrition 0.000 description 2
- 230000003068 static effect Effects 0.000 description 2
- WGTYBPLFGIVFAS-UHFFFAOYSA-M tetramethylammonium hydroxide Chemical compound [OH-].C[N+](C)(C)C WGTYBPLFGIVFAS-UHFFFAOYSA-M 0.000 description 2
- 238000005406 washing Methods 0.000 description 2
- 235000016068 Berberis vulgaris Nutrition 0.000 description 1
- 241000335053 Beta vulgaris Species 0.000 description 1
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
- 244000166124 Eucalyptus globulus Species 0.000 description 1
- 241000967320 Gentianella quinquefolia Species 0.000 description 1
- WQZGKKKJIJFFOK-GASJEMHNSA-N Glucose Natural products OC[C@H]1OC(O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-GASJEMHNSA-N 0.000 description 1
- 229920002683 Glycosaminoglycan Polymers 0.000 description 1
- AYRXSINWFIIFAE-SCLMCMATSA-N Isomaltose Natural products OC[C@H]1O[C@H](OC[C@@H](O)[C@@H](O)[C@H](O)[C@@H](O)C=O)[C@@H](O)[C@@H](O)[C@@H]1O AYRXSINWFIIFAE-SCLMCMATSA-N 0.000 description 1
- 108091005804 Peptidases Proteins 0.000 description 1
- 239000004365 Protease Substances 0.000 description 1
- 102100037486 Reverse transcriptase/ribonuclease H Human genes 0.000 description 1
- 230000001133 acceleration Effects 0.000 description 1
- AZDRQVAHHNSJOQ-UHFFFAOYSA-N alumane Chemical class [AlH3] AZDRQVAHHNSJOQ-UHFFFAOYSA-N 0.000 description 1
- 159000000013 aluminium salts Chemical class 0.000 description 1
- 229910000329 aluminium sulfate Inorganic materials 0.000 description 1
- 238000004523 catalytic cracking Methods 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 239000008139 complexing agent Substances 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 238000009833 condensation Methods 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 235000012343 cottonseed oil Nutrition 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 230000029087 digestion Effects 0.000 description 1
- 150000002016 disaccharides Chemical class 0.000 description 1
- 239000002270 dispersing agent Substances 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 239000012013 faujasite Substances 0.000 description 1
- 238000009472 formulation Methods 0.000 description 1
- 229930182830 galactose Natural products 0.000 description 1
- 239000008103 glucose Substances 0.000 description 1
- 235000011187 glycerol Nutrition 0.000 description 1
- 235000020256 human milk Nutrition 0.000 description 1
- 210000004251 human milk Anatomy 0.000 description 1
- 239000000413 hydrolysate Substances 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 239000004615 ingredient Substances 0.000 description 1
- 238000003780 insertion Methods 0.000 description 1
- 230000037431 insertion Effects 0.000 description 1
- DLRVVLDZNNYCBX-RTPHMHGBSA-N isomaltose Chemical compound O[C@@H]1[C@@H](O)[C@H](O)[C@@H](CO)O[C@@H]1OC[C@@H]1[C@@H](O)[C@H](O)[C@@H](O)C(O)O1 DLRVVLDZNNYCBX-RTPHMHGBSA-N 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 229920005615 natural polymer Polymers 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- TZMFJUDUGYTVRY-UHFFFAOYSA-N pentane-2,3-dione Chemical compound CCC(=O)C(C)=O TZMFJUDUGYTVRY-UHFFFAOYSA-N 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 239000012266 salt solution Substances 0.000 description 1
- 239000001509 sodium citrate Substances 0.000 description 1
- 239000011775 sodium fluoride Substances 0.000 description 1
- 235000013024 sodium fluoride Nutrition 0.000 description 1
- 229960000414 sodium fluoride Drugs 0.000 description 1
- 235000019795 sodium metasilicate Nutrition 0.000 description 1
- ZNCPFRVNHGOPAG-UHFFFAOYSA-L sodium oxalate Chemical compound [Na+].[Na+].[O-]C(=O)C([O-])=O ZNCPFRVNHGOPAG-UHFFFAOYSA-L 0.000 description 1
- 229940039790 sodium oxalate Drugs 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 229920002994 synthetic fiber Polymers 0.000 description 1
- HRXKRNGNAMMEHJ-UHFFFAOYSA-K trisodium citrate Chemical compound [Na+].[Na+].[Na+].[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O HRXKRNGNAMMEHJ-UHFFFAOYSA-K 0.000 description 1
- 229940038773 trisodium citrate Drugs 0.000 description 1
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- Silicates, Zeolites, And Molecular Sieves (AREA)
Abstract
一种NaY分子筛的合成方法，包括合成导向剂、合成凝胶、晶化、回收的步骤，其特征在于，在合成凝胶或晶化过程中引入一种与凝胶中Al2O3的重量比为0.1-3∶1的添加剂，所述添加剂为甲壳素和/或寡糖。本发明方法可合成高硅铝比的小晶粒NaY分子筛。A kind of synthetic method of NaY molecular sieve, comprises the steps of synthesizing directing agent, synthesizing gel, crystallization, reclaiming, it is characterized in that, in synthesizing gel or crystallization process, introduce a kind of weight with Al 2 O 3 in gel An additive with a ratio of 0.1-3:1, said additive being chitin and/or oligosaccharides. The method of the invention can synthesize small-grain NaY molecular sieves with high silicon-aluminum ratio.
Description
Technical field
The present invention relates to a kind of synthetic method of NaY molecular sieve.
Background technology
By the molecular sieve modified Y zeolite that obtains of NaY is the main active component of catalytic cracking catalyst, and its grain size has bigger influence to the cracking performance of FCC catalyzer.Because the restriction of interior diffusion, big molecule is difficult to go deep in the hole of larger crystal molecular sieve in a lot of situations, so the accessibility in its activated centre is poor.Small crystal grain molecular sieve has bigger outer surface area and Geng Duo outside surface active centre, and internal diffusion path, hole is shorter, and the active centre accessibility is higher, and the utilization ratio of internal surface active sites improves.
In the use of FCC catalyzer, the thermal and hydric environment of revivifier can make the framework dealumination of Y zeolite, reduces the stability of catalyzer.Studies show that the hydrothermal stability of molecular sieve and its framework si-al ratio are closely related, framework si-al ratio height, the good hydrothermal stability of molecular sieve.
The directing agent method that the method for present industrial production NaY molecular sieve adopts U.S. Grace company to propose in US3639099 and US3671191 mostly.This method at first is that the preparation mole consists of (15-17) Na
2O: Al
2O
3: (14-16) SiO
2: (285-357) H
2The directed agents of O, the nucleus diamter of directed agents be usually less than 0.05 micron, again with raw materials such as directed agents and waterglass, sodium metaaluminate, aluminum sulfate according to mol ratio (3-6) Na
2O: Al
2O
3: (8-12) SiO
2: (120-200) H
2The ratio of O is mixed with gel, then with this gel 100 ℃ of left and right sides crystallization.This method synthetic NaY framework of molecular sieve silica alumina ratio about 5.0, generally is lower than 5.2 usually, and grain size is generally 500-800nm.
The method of existing synthesizing small-grain NaY molecular sieve comprises following several:
1. change system basicity.
EP 0435625A2 has disclosed by changing the method for synthetic system basicity and high speed shear synthesizing small-grain NaY molecular sieve.
2. change directed agents character.
US 3755538 has disclosed metals such as introducing B, V, P, Co in directed agents or has changed the method that directed agents is come synthesizing small-grain NaY by factors such as control digestion time, temperature.
CN 1033503C provides a kind of method that the directed agents technology prepares small crystal grain NaY molecular sieve of improving that adopts.Its preparation process is: at first sodium silicate solution is joined in the conventional directed agents of transmittance＜30%, make a kind of mole and consist of (12-180) Na
2O: Al
2O
3: (17-210)) SiO
2: (160-3100) H
2The improvement directed agents solution of O, transmittance＞75%, will improving directed agents then, to be used for the NaY hydro-thermal of different ingredients synthetic, makes the small crystal grain NaY molecular sieve product according to the preparation method of conventional NaY molecular sieve.
CN 1176848A provides a kind of method of synthetic small granular NaY molecular sieve, its preparation process is to prepare earlier conventional directed agents, alcohol solvent is joined in the conventional directed agents then, so that directed agents concentrates, after aging 2-20 hour, make a kind of light transmittance of high concentration＞30%, mole consists of (10-30) Na
2O: Al
2O
3: (10-21) SiO
2: (100-400) H
2The improvement directed agents of O with improving the NaY zeolite-water thermal synthesis of directed agents for different formulations, can make the small granular NaY molecular sieve about 0.1-0.3 μ m.
CN 1160676A has disclosed a kind of method for preparing fine-grain NaY zeolite, this method is to prepare according to a conventional method directed agents, then with the whole silicon source of the silicon in this directed agents as synthetic material, the aluminum salt solution of acidifying is under agitation mixed with this directed agents, meet (1.5-5) Na so that the mole of mixture forms
2O: Al
2O
3: (6-10) SiO
2: (150-300) H
2The proportioning of O is then with this mixture crystallization according to a conventional method, after filtration, to obtain crystal grain after the washing be 0.1-0.5 micron, silica alumina ratio more than or equal to 5.0, degree of crystallinity and heat and hydrothermal stability fine-grain NaY zeolite preferably.
A kind of method for preparing small crystal grain NaY molecular sieve is provided among the CN 1113814C.This method is different from conventional method when the preparation directed agents, directed agents is divided a few step preparations: at first add sodium silicate solution in high alkali deflection aluminium acid sodium solution, mix and blend leaves standstill aging; Add then for example glycerine of organic dispersing agent; Continue to add sodium silicate solution, mix and blend leaves standstill aging again.Be directed agents and aluminum sulfate solution, low alkali aluminium acid sodium solution and sodium silicate solution mix and blend with the above-mentioned mixture that makes, crystallization is filtered, and drying can make small crystal grain NaY molecular sieve.
3. optimization synthesis step.
Disclose a kind of method for preparing nanometer NaY zeolite among the CN 1133585C, this method is not add any additive, normal temperature batching, the NaY (SiO of synthetic granularity 30-70nm in the situation of conventional equipment
2/ Al
2O
3=3-5) zeolite, and can be by simple control, regulate crystallization condition and batching make a series of size distribution at variable grain size, the silica alumina ratio close NaY zeolite of 30nm to 250nm.
4 change process conditions.
GB1223592, EP41659 have reported that with the USP4587115 philosophy shortcoming of this method is that the product silica alumina ratio is low by the method that acceleration is stirred, low temperature becomes the mode synthesizing small-grain NaY such as glue.
People such as Zhongming Liu are at Material Letters, 60 (2006), disclose two sections variable temperature crystallizations of a kind of employing among the 1131-1133, do not added the NaY method in the synthetic particle diameter 0.12-0.85 mu m range of template, structure directing agent, crystal seed and other additive.In the building-up process, used gel consists of 10Na
2O: 1Al
2O
3: 15SiO
2: 200H
2O, two sections variable temperature crystallization programs are at 40 ℃ of lower crystallization 24h, 60 ℃ of lower crystallization 48h.
People such as Melkon Tatlier are at J.Cryst.Growth, 241 (2002), disclose among the 481-488, the aging NaY that can obtain the less and narrow distribution of crystal grain under subambient condition, low alkalinity gel agingly under the condition under the room temperature can promote Si insertion rate being lower than.
Li Qinghua etc. are at Chem.Mater., 14 (2002), among the 1319-1324 with Tetramethylammonium hydroxide (TMAOH5H
2O) under the transparent liquid phase synthetic system as template, by the synthetic NaY of particle diameter about 100nm of two sections variable temperature crystallization methods.
5. interpolation organic substance.
Linder is at Zeolites, 1996,16 (3): disclosed among the 196-206 in synthetic system and to add the method that can form the synthetic NaY molecular sieve of organic complexing agent of stable comple, found to add methyl ethyl diketone, Trisodium Citrate, Sodium Fluoride, sodium oxalate and aminopolycanboxylic acid the particle diameter of institute's synthetic molecular sieve is reduced with Al.
Disclosed among the US 4372931 under condensation point to 10 ℃ low temperature and become glue, and in synthetic system, added monose or disaccharides, the method for synthesizing small-grain faujasite molecular sieve.This method needs synthetic at low temperatures.
Wang Bo has disclosed among (2002) 385-388 with starch as space constraint agent synthesis of nano NaY molecular sieve method at Chinese Chemical Letters 13.
Yushan Yan etc. has reported in JACS 125 (2003) 9928 and has a kind ofly controlled crystalline growth velocity with the Thermoreversibly water-sol, adjusts the synthetic method of the NaY molecular sieve of grain size.
Summary of the invention
The method that the purpose of this invention is to provide a kind of new synthesizing small-grain NaY molecular sieve.
The invention provides a kind of synthetic method of NaY molecular sieve, comprise the step of synthetic directed agents, synthesized gel rubber, crystallization, recovery, it is characterized in that, in synthesized gel rubber or crystallization process, introduce Al in a kind of and the gel
2O
3Weight ratio be 0.1-3: 1 additive, described additive are chitin and/or oligosaccharides.
NaY synthetic method of the present invention, at normal temperatures synthetic, do not need to change flow process and the equipment that has the NaY Zeolite synthesis now, and crystallization time is short; The zeolite crystal particle diameter that is synthesized is little, can be between 200-450nm, and the silica alumina ratio height, can reach more than 5.5.
Embodiment
In the synthetic method provided by the invention, Al in additive and the gel
2O
3Weight ratio be preferably 0.5-2: 1.Described additive is selected from one or more in oligosaccharides and the chitin.Oligosaccharides claims oligose again, be 2-10 the sugar that the monose molecule connects into, comprise: low poly lactose, oligomeric galactose, oligofructose, oligomeric isomaltose, palatinose, oligomeric dragon gallbladder sugar, soybean oligosaccharide, raffinose, stachyose etc. mainly are present in the protease hydrolysate of human milk, soybean, cottonseed, eucalyptus, beet, agueweed root and starch.Oligosaccharides is general incomplete hydrolysis in the aqueous solution.Chitin claims again Chitin, is the unique positively charged a kind of natural polymers of occurring in nature, belongs to the straight chain glycosaminoglycan, and formal name used at school is [(Isosorbide-5-Nitrae)-2-acetylaminohydroxyphenylarsonic acid 2-deoxidation-β-D-Portugal glucose], and molecular formula is (C
8H
13NO
5)
n, chitin facile hydrolysis not in the aqueous solution.
In the synthetic method provided by the invention, described synthetic directed agents can be carried out according to the method for synthetic NaY molecular sieve guiding agent in the prior art, for example with sodium metasilicate, sodium metaaluminate, alkali lye and deionized water, according to (11-18) Na
2O: Al
2O
3: (10-17) SiO
2: (200-380) H
2The mixed in molar ratio of O is after stirring, at room temperature to 70 ℃ lower aging 0.5-200h.
In the synthetic method provided by the invention, described additive is introduced in the synthesized gel rubber process or in the crystallization process.When introducing additive in the synthesized gel rubber process, described additive is introduced in synthetic any step, for example introduces behind sodium metaaluminate or before the directed agents.Described synthesized gel rubber is a prior art, is included in to add directed agents, acid aluminium salt, sodium metaaluminate in the water glass successively, stirs, and the consumption of each component makes the preferred mole of prepared gel consist of (1-6) Na
2O: Al
2O
3: (5.5-16) SiO
2: (100-240) H
2O, more preferably (1.4-3.6) Na
2O: Al
2O
3: (6-10) SiO
2: (150-220) H
2O.Wherein the addition of preferred directed agents makes the Al that introduces by directed agents
2O
3Amount accounts for Al in the gel
2O
3The 0.1-10 weight % of total amount, more preferably 1-8 weight %.
In the synthetic method provided by the invention, when in crystallization process, introducing additive, preferably introduce additive after crystallization time be at least 10 hours, preferred described additive is introduced during crystallization 8-16h.Crystallization of the present invention is compared with existing NaY molecular sieve synthetic crystallization process, does not have particular requirement, and preferred crystallization temperature is 80-120 ℃, and crystallization time is 10-55h.
In the synthetic method provided by the invention, the method for described recovery comprises filtration, washing, exsiccant step, is well known to those skilled in the art, and the present invention does not have particular requirement.
Following embodiment further specifies the present invention, and among the embodiment, the size of microcrystal of molecular sieve adopts scanning electron microscope (SEM) to measure.
Embodiment 1
Get 100ml waterglass (Chang Ling oil-refining chemical factory catalyst plant product, proportion 1.26, SiO
2Content 255.8g/L, modulus 3.24) put into a beaker, add the high sodium aluminate solution of 70.7g (Chang Ling oil-refining chemical factory catalyst plant product, proportion 1.33, Al
2O
3Content 41g/L, Na
2O content 280g/L), after mixing, in aged at room temperature 24h, namely get required directed agents, its mole proportioning is 16Na
2O: Al
2O
3: 15SiO
2: 320H
2O.
According to 2.76Na
2O: Al
2O
3: 8.4SiO
2: 209H
2The mole proportioning of O is synthesized the NaY molecular sieve.Under stirring, successively with 189ml deionized water, 16g FOS (Beijing chemical reagents corporation, molecular weight 900, purity 90%, 2-8 sugar), 88g directed agents, 130ml aluminum sulfate solution (Chang Ling oil-refining chemical factory catalyst plant product, proportion 1.28, Al
2O
3Content 88.2g/L) and 100ml low sodium aluminate solution (Chang Ling oil-refining chemical factory catalyst plant product, proportion 1.23, Al
2O
3Content 102g/L, Na
2O content 151.9g/L) be added in the 415ml waterglass (specification is the same), the ratio of aluminium oxide is 0.63: 1 in oligosaccharides and the gel, adds rear strong agitation 30min, in 100 ℃ leave standstill crystallization 33h after, stop crystallization.Recording the NaY molecular sieve crystallinity that is synthesized with x-ray diffraction method is 93.1%, SiO
2/ Al
2O
3(mol ratio) is 5.81, and size of microcrystal is 200-350nm.
Embodiment 2
Get 100ml waterglass (Chang Ling oil-refining chemical factory catalyst plant product, proportion 1.26, SiO
2Content 255.8g/L, modulus 3.24) put into a beaker, add the high sodium aluminate solution of 70.7g (Chang Ling oil-refining chemical factory catalyst plant product, proportion 1.33, Al
2O
3Content 41g/L, Na
2O content 280g/L), after mixing, in aged at room temperature 24h, namely get required directed agents, its mole proportioning is 16Na
2O: Al
2O
3: 15SiO
2: 320H
2O.
According to 2.76Na
2O: Al
2O
3: 8.4SiO
2: 209H
2The mole proportioning of O is synthesized the NaY molecular sieve: under stirring, successively with 189ml deionized water, 60g FOS (with embodiment 1 oligosaccharides), 88g directed agents, 130ml aluminum sulfate solution (Chang Ling oil-refining chemical factory catalyst plant product, proportion 1.28, Al
2O
3Content 88.2g/L) and 100ml low sodium aluminate solution (Chang Ling oil-refining chemical factory catalyst plant product, proportion 1.23, Al
2O
3Content 102g/L, Na
2O content 151.9g/L) be added in the 415ml waterglass (specification is the same), the ratio of aluminium oxide is 2.35: 1 in oligosaccharides and the gel, adds rear strong agitation 30min, behind 100 ℃ of static crystallization 33h, stops crystallization.Recording the NaY molecular sieve crystallinity that is synthesized with x-ray diffraction method is 88%, SiO
2/ Al
2O
3Be 5.85, size of microcrystal is 200-450nm.
Embodiment 3
Get 100ml waterglass (Chang Ling oil-refining chemical factory catalyst plant product, proportion 1.26, SiO
2Content 255.8g/L, modulus 3.24) put into a beaker, add the high sodium aluminate solution of 70.7g (Chang Ling oil-refining chemical factory catalyst plant product, proportion 1.33, Al
2O
3Content 41g/L, Na
2O content 280g/L), after mixing, in aged at room temperature 24h, namely get required directed agents, its mole proportioning is 16Na
2O: Al
2O
3: 15SiO
2: 320H
2O.
According to 2.76Na
2O: Al
2O
3: 8.4SiO
2: 209H
2The mole proportioning of O is under stirring, successively with 189ml deionized water, 88g directed agents, 130ml aluminum sulfate solution (Chang Ling oil-refining chemical factory catalyst plant product, proportion 1.28, Al
2O
3Content 88.2g/L) and 100ml low sodium aluminate solution (Chang Ling oil-refining chemical factory catalyst plant product, proportion 1.23, Al
2O
3Content 102g/L, Na
2O content 151.9g/L) is added in the 415ml waterglass (specification is the same), add rear strong agitation 30min, left standstill crystallization 8 hours in 100 ℃, adding 10g chitin (Beijing chemical reagents corporation, molecular weight: 10000, purity: 99%, together lower), the ratio of aluminium oxide is 0.43: 1 in chitin and the gel, stirs, and stops crystallization after leaving standstill crystallization 25h.Recording the NaY molecular sieve crystallinity that is synthesized with x-ray diffraction method is 93.1%, SiO
2/ Al
2O
3Be 5.65, size of microcrystal is 200-400nm.
Embodiment 4
Get 100ml waterglass (Chang Ling oil-refining chemical factory catalyst plant product, proportion 1.26, SiO
2Content 255.8g/L, modulus 3.24) put into a beaker, add the high sodium aluminate solution of 70.7g (Chang Ling oil-refining chemical factory catalyst plant product, proportion 1.33, Al
2O
3Content 41g/L, Na
2O content 280g/L), after mixing, in aged at room temperature 24h, namely get required directed agents, its mole proportioning is 16Na
2O: Al
2O
3: 15SiO
2: 320H
2O.
The NaY molecular sieve is according to 2.76Na
2O: Al
2O
3: 8.4SiO
2: 209H
2The mole proportioning of O is synthetic: under stirring, successively with 189ml deionized water, 3g chitin, 86.6g directed agents, 130ml aluminum sulfate solution (Chang Ling oil-refining chemical factory catalyst plant product, proportion 1.28, Al
2O
3Content 88.2g/L) and 100ml low sodium aluminate solution (Chang Ling oil-refining chemical factory catalyst plant product, proportion 1.23, Al
2O
3Content 102g/L, Na
2O content 151.9g/L) be added in the 401ml waterglass (specification is the same), the ratio of aluminium oxide is 0.13: 1 in chitin and the gel, adds rear strong agitation 30min, in 100 ℃ leave standstill crystallization 33h after, stop crystallization.Recording the NaY molecular sieve crystallinity that is synthesized with x-ray diffraction method is 91.1%, SiO
2/ Al
2O
3Be 5.73, size of microcrystal is 200-450nm.
Embodiment 5
Get 100ml waterglass (Chang Ling oil-refining chemical factory catalyst plant product, proportion 1.26, SiO
2Content 255.8g/L, modulus 3.24) put into a beaker, add the high sodium aluminate solution of 70.7g (Chang Ling oil-refining chemical factory catalyst plant product, proportion 1.33, Al
2O
3Content 41g/L, Na
2O content 280g/L), after mixing, in aged at room temperature 24h, namely get required directed agents, its mole proportioning is 16Na
2O: Al
2O
3: 15SiO
2: 320H
2O.
According to 2.76Na
2O: Al
2O
3: 8.4SiO
2: 209H
2The mole proportioning of O is synthesized the NaY molecular sieve.Under stirring, successively with 189ml deionized water, 13g chitosan oligosaccharide (Beijing chemical reagents corporation, molecular weight: 1500, purity: 70%, 2-8 sugar, lower with), 88g directed agents, 130ml aluminum sulfate solution (Chang Ling oil-refining chemical factory catalyst plant product, proportion 1.28, Al
2O
3Content 88.2g/L) and 100ml low sodium aluminate solution (Chang Ling oil-refining chemical factory catalyst plant product, proportion 1.23, Al
2O
3Content 102g/L, Na
2O content 151.9g/L) be added in the 415ml waterglass (specification is the same), the ratio of aluminium oxide is 0.39: 1 in oligosaccharides and the gel, adds rear strong agitation 30min, in 100 ℃ leave standstill crystallization 33h after, stop crystallization.Recording the NaY molecular sieve crystallinity that is synthesized with x-ray diffraction method is 93.1%, SiO
2/ Al
2O
3(mol ratio) is 5.51, and size of microcrystal is 200-450nm.
Embodiment 6
Get 100ml waterglass (Chang Ling oil-refining chemical factory catalyst plant product, proportion 1.26, SiO
2Content 255.8g/L, modulus 3.24) put into a beaker, add the high sodium aluminate solution of 70.7g (Chang Ling oil-refining chemical factory catalyst plant product, proportion 1.33, Al
2O
3Content 41g/L, Na
2O content 280g/L), after mixing, in aged at room temperature 24h, namely get required directed agents, its mole proportioning is 16Na
2O: Al
2O
3: 15SiO
2: 320H
2O.
According to 2.76Na
2O: Al
2O
3: 8.4SiO
2: 209H
2The mole proportioning of O is synthesized the NaY molecular sieve.Under stirring, successively with 189ml deionized water, 88g directed agents, 130ml aluminum sulfate solution (Chang Ling oil-refining chemical factory catalyst plant product, proportion 1.28, Al
2O
3Content 88.2g/L) and 100ml low sodium aluminate solution (Chang Ling oil-refining chemical factory catalyst plant product, proportion 1.23, Al
2O
3Content 102g/L, Na
2O content 151.9g/L) is added in the 415ml waterglass (specification is the same), adds rear strong agitation 30min, left standstill crystallization 16 hours in 100 ℃, adding the 86g chitosan oligosaccharide stirs evenly, the ratio of aluminium oxide is 2.62: 1 in oligosaccharides and the gel, leave standstill crystallization 17h after, stop crystallization.Recording the NaY molecular sieve crystallinity that is synthesized with x-ray diffraction method is 93.1%, SiO
2/ Al
2O
3(mol ratio) is 5.81, and size of microcrystal is 200-450nm.
Comparative Examples 1
Get 100ml waterglass (Chang Ling oil-refining chemical factory catalyst plant product, proportion 1.26, SiO
2Content 255.8g/L, modulus 3.24) put into a beaker, add the high sodium aluminate solution of 70.7g (Chang Ling oil-refining chemical factory catalyst plant product, proportion 1.33, Al
2O
3Content 41g/L, Na
2O content 280g/L), after mixing, in aged at room temperature 24h, namely get required directed agents, its mole proportioning is 16Na
2O: Al
2O
3: 15SiO
2: 320H
2O.
The NaY molecular sieve is according to 2.76Na
2O: Al
2O
3: 8.4SiO
2: 209H
2The proportioning of O is synthetic.Under stirring, successively with 189ml deionized water, 86.6g directed agents, 130ml aluminum sulfate solution (Chang Ling oil-refining chemical factory catalyst plant product, proportion 1.28, Al
2O
3Content 88.2g/L) and 100ml low sodium aluminate solution (Chang Ling oil-refining chemical factory catalyst plant product, proportion 1.23, Al
2O
3Content 102g/L, Na
2O content 151.9g/L) is added in the 401ml waterglass (specification is the same), adds rear strong agitation 30min, behind 100 ℃ of static crystallization 33h, stop crystallization.Recording the NaY molecular sieve crystallinity that is synthesized with x-ray diffraction method is 93.1%, SiO
2/ Al
2O
3Be 5.13, size of microcrystal 400-800nm.
Claims (9)
1. the synthetic method of a NaY molecular sieve comprises it is characterized in that the step of synthetic directed agents, synthesized gel rubber, crystallization, recovery, introduces Al in a kind of and the gel in synthesized gel rubber or crystallization process
2O
3Weight ratio be 0.1-3: 1 additive, described additive is for hanging down one or more in poly lactose, galactooligosaccharide, FOS, oligoisomaltose, palatinose, oligomeric dragon gallbladder sugar, soyabean oligosaccharides, raffinose, stachyose and the chitin, and described gel consists of (1-6) Na
2O: Al
2O
3: (5.5-16) SiO
2: (100-240) H
2O.
2. in accordance with the method for claim 1, it is characterized in that Al in described additive and the gel
2O
3Weight ratio be 0.1-2: 1.
3. in accordance with the method for claim 1, it is characterized in that described gel consists of (1.4-3.6) Na
2O: Al
2O
3: (6-10) SiO
2: (150-220) H
2O.
4. in accordance with the method for claim 1, it is characterized in that the aluminium oxide that is derived from directed agents in the described gel accounts for Al in the gel
2O
3The 0.1-10 weight % of total amount.
5. in accordance with the method for claim 4, it is characterized in that the aluminium oxide that is derived from directed agents in the described gel accounts for Al in the gel
2O
3The 1-8 weight % of total amount.
6. in accordance with the method for claim 1, it is characterized in that described additive was introduced before 16 hours in crystallization.
7. in accordance with the method for claim 5, it is characterized in that described additive is introduced during 8～16 hours in crystallization.
8. according to claim 1 or 5 described methods, it is characterized in that, after described additive is introduced, crystallization at least 10 hours.
9. the synthetic method of a NaY molecular sieve comprises it is characterized in that the step of synthetic directed agents, synthesized gel rubber, crystallization, recovery, introduces Al in a kind of and the gel in synthesized gel rubber or crystallization process
2O
3Weight ratio be 0.1-3: 1 additive, described gel consist of (1-6) Na
2O: Al
2O
3: (5.5-16) SiO
2: (100-240) H
2O; Described additive is chitosan oligosaccharide.
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| CN102942192A (en) * | 2012-11-18 | 2013-02-27 | 大连理工大学 | Preparation method for high-dispersion nanometer zeolite molecular sieve |
| CN106542541A (en) * | 2016-11-08 | 2017-03-29 | 上海纳米技术及应用国家工程研究中心有限公司 | A kind of small size NaA zeolite molecular sieve and preparation method thereof |
| CN111825105B (en) * | 2019-04-18 | 2022-08-19 | 中国科学院大连化学物理研究所 | Preparation of Y molecular sieve with FAU structure by guide agent method |
| CN116553574A (en) * | 2022-01-28 | 2023-08-08 | 中国石油化工股份有限公司 | A kind of nanometer BETA molecular sieve and synthetic method thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4372931A (en) * | 1980-05-30 | 1983-02-08 | Air Products And Chemicals, Inc. | Microcrystalline synthetic faujasite |
| CN1621348A (en) * | 2003-11-28 | 2005-06-01 | 中国石油化工股份有限公司 | Synthesis method of NaY molecular sieve |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4372931A (en) * | 1980-05-30 | 1983-02-08 | Air Products And Chemicals, Inc. | Microcrystalline synthetic faujasite |
| CN1621348A (en) * | 2003-11-28 | 2005-06-01 | 中国石油化工股份有限公司 | Synthesis method of NaY molecular sieve |
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