CN103449468B - Synthesis method of NaY molecular sieve - Google Patents
Synthesis method of NaY molecular sieve Download PDFInfo
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- CN103449468B CN103449468B CN201210168420.1A CN201210168420A CN103449468B CN 103449468 B CN103449468 B CN 103449468B CN 201210168420 A CN201210168420 A CN 201210168420A CN 103449468 B CN103449468 B CN 103449468B
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Abstract
The invention relates to a synthesis method of an NaY molecular sieve. The method includes: mixing water glass, sodium metaaluminate and deionized water, conducting aging at 15-70DEG C for 0.5-48h to obtain a crystallization guiding agent; mixing the crystallization guiding agent, water glass, an acidic aluminum salt and a sodium aluminate solution uniformly to obtain a silica-alumina gel; crystallizing the silicon-aluminum gel at 80-140DEG C for 0.1- 80h; adding a peroxide into the crystallized silicon-aluminum gel, making molar ratio of the 02<2-> in the peroxide to the Al2O3 in the gel at 0.05-20, then further conducting crystallization for 5-20h, thus obtaining the NaY molecular sieve. Without adding any organic or inorganic template and being free of multiple after-treatment modification processes, the method can directly prepare the Y type molecular sieve with a high silicon-aluminum ratio. The obtained molecular sieve has crystallinity up to over 80%, a silicon-aluminum ratio of not less than 5.8, and an average grain size of 200-300.
Description
Technical field
The present invention relates to a kind of synthetic method of NaY molecular sieve, relate to the method that synthesis has the NaY zeolite compared with high silica alumina ratio specifically.
Background technology
In recent years, stock oil becomes heavy increasingly, uses conventional cracking catalyst to be difficult to meet the requirement of development gradually.How more fully, more effective make good use of the focal issue that limited petroleum resources become refining of petroleum.The catalytic cracking catalyst of China is mainly based on Y-type rare earth catalyzer, and Y zeolite is the main active component of cracking catalyst, the cracking activity of molecular sieve and selectivity directly affects the product slates of cracking reaction, its degree of crystallinity, silica alumina ratio, pore structure and acid distribution etc. on catalytic performance impact research always by people are paid close attention to.
The Grace company of the U.S. comparatively early proposes the method synthesis NaY molecular sieve utilizing crystallization director.At disclosed patent USP3,639,099 and USP3,671, propose in 191 and use crystallization director method synthesis NaY molecular sieve, the method first prepares to consist of (15 ~ 17) Na
2o:Al
2o
3: (14 ~ 16) SiO
2: (285 ~ 357) H
2the crystallization director of O, the directed agents nucleus diamter obtained is generally less than 0.05 micron, then this directed agents is mixed with into water glass, sodium aluminate, acid aluminium salt etc. and consists of (3 ~ 6) Na
2o:Al
2o
3: (8 ~ 12) SiO
2: (120 ~ 200) H
2the reaction mixture of O, then by this reaction mixture about 100 DEG C crystallization.The shortcoming of the method is that the water yield that feeds intake is higher, SiO in mother liquor
2quantity discharged is higher, reduces the utilization ratio of silicon, and the NaY molecular sieve framework si-al ratio of synthesis (is SiO below
2/ Al
2o
3mol ratio) general lower than 5.2.After this people improve on this method basis, develop into the synthetic method adding different templates agent, but due to the restriction by electrochemical conditions in building-up process, the silica alumina ratio of the NaY molecular sieve that the method obtains all about 5.0, generally lower than 5.5.
The structures and characteristics of the framework silicon-aluminum comparison of Y zeolite self has a direct impact.Improve skeleton Si/Al ratio, reduce Al center density, improve the relative intensity in acid site, contribute to the ratio changing cracking/hydrogen transfer activity, reduce the generation of catalysis Jiao; Because high silica alumina ratio Y molecular sieve structure cell shrinks, there is good hydrothermal stability and acid acceptance, reaction-regeneration condition harsh in catalytic cracking process can be born; In addition, its catalytic selectivity is good, and contributing to increases yield of gasoline, improves octane value.
Current, the active component of the heavy oil fluid catalytic cracking of widespread use generally adopts the method for the aftertreatment such as dealuminzation or dealumination complement silicon, is namely the parent NaY that alkaline system synthesizes is carried out dealuminzation, dealumination complement silicon to obtain high silicon Y molecular sieve.Advantage is easy industrialization, and shortcoming is that technical process is complicated, and the degree of crystallinity of NaY molecular sieve declines, and generates a large amount of non-framework aluminums etc.
Adopt the method for template method high silica alumina ratio NaY molecular sieve, mainly contain following reported in literature.
Patent USP 4,714,601, USP 4,931,267, USP 5,116,590, USP 5,549, in 881, the people such as Vanghan and DavidE.W has synthesized a series of high silicon faujusite isomorph, respectively called after ECR-4, ECR-32 and ECR-35.Its silica alumina ratio (SiO2/Al2O3 mol ratio) is between 6.0-30.0.The principal feature of this technology is exactly in silica-alumina gel, add organic formwork agent as the one in Tetramethylammonium hydroxide, TPAOH or TBAH or its mixture.The mol ratio preparing each oxide compound of the reaction mixture of this molecular sieve is: 0.02 ~ 0.40T
2o:0.60 ~ 0.98Na
2o:Al
2o
3: 4 ~ 12SiO
2: 0 ~ 25H
2o, T represent alkyl ammonium ion.Silicon source used can be white carbon black, silica gel, silicon sol and water glass etc., and aluminium source can be alchlor, intends rich diaspore, sodium aluminate or Tai-Ace S 150 etc.It is comparatively simple that this method has preparation process, and zeolite crystallinity does not incur loss, and technical process is fairly simple, without many advantages such as (or few) environmental pollutions.But these methods template used is as very expensive in tetrapropyl ammonium alkali price, in addition, adopt the method to want to obtain the NaY molecular sieve of high-crystallinity high silica alumina ratio, need the crystallization time of tens days, and productive rate is lower.Grace company (USP4,333,859) develops a kind of method adding cesium ion synthetic faujasites in reactant gel, between obtained CSZ-1, CSZ-3 Series Molecules sieve silica alumina ratio 5.0 ~ 7.0.But the bad removing of cesium ion in this kind of method product, needs repeatedly to exchange and roasting, considerably increases production cost.
Develop without the synthetic method of template, direct synthesizing Si-Al is than more than 5.5, and even the NaY molecular sieve product of high silica alumina ratio of about 6.0 has great importance.
Patent GB1,044,983 disclose and prepare silica alumina ratio and be about: Y zeolite method between 3 ~ 7.This patent is pointed out, if think the y-type zeolite of high silica alumina ratio processed, be necessary to make silica alumina ratio in reactant between 7 ~ 40, when the silica alumina ratio in reaction-ure mixture is between 7 ~ 40, just need to place the longer time (about 20 ~ 40 hours or longer) in room temperature, high temperature crystallization time also long (4 ~ 6 days) just can obtain the product of expecting.Its shortcoming is that crystallization time is long, and institute's preferred feedstock silicon sol high cost, silicon source utilization ratio is also very low.
USP3574538 reports and a kind of uses metakaolin, water glass, sodium hydroxide, and crystal seed synthesizing Si-Al is than the method for NaY zeolite reaching 6.0.Its advantage is that raw material availability is high, and shortcoming is that the Property requirements of raw material metakaolin is higher, and industry not easily reaches requirement.
CN 1785807 patent discloses and adopts non-template agent direct synthesis technique two step crystallization to synthesize SiO
2/ Al
2o
3it is the high-silicon Y-Zeolite of 6.0 ~ 6.5.Product degree of crystallinity is high, and crystal grain is little, has satisfactory stability and catalytic activity.
2006, CN 1789125A [31] patent discloses a kind of method of high silica alumina ratio, small crystal grain NaY molecular sieve.First conventionally synthesize NaY molecular sieve directed agents, then obtain gel with water glass, directed agents, acid aluminium salt and sodium metaaluminate, by gel at 50 ~ 100 DEG C after crystallization 0 ~ 70h, add silicon source, crystallization 0.5 ~ 50h is continued again at 90 ~ 120 DEG C, product silica alumina ratio 5.5 ~ 7.0.The shortcoming of the method is that silicon source utilization ratio is on the low side, and production cost significantly increases.
Summary of the invention
Under the object of this invention is to provide a kind of prerequisite substantially not changing conventional synthesis technique, the novel synthesis of NaY molecular sieve product silica alumina ratio can be improved.Compared with the conventional method, high silica alumina ratio NaY molecular sieve can be synthesized in the short period of time, obtain the NaY molecular sieve of little crystal grain simultaneously.
The method concrete steps of synthesis NaY molecular sieve provided by the invention are as follows:
(1) by water glass, sodium metaaluminate and deionized water according to 11 ~ 18Na
2o:Al
2o
3: 11 ~ 18SiO
2: 200 ~ 380H
2the mixed in molar ratio of O, after stirring, obtains crystallization director in aging 0.5 ~ 48 hour at 15-70 DEG C;
(2) crystallization director, water glass, acid aluminium salt and sodium aluminate solution are mixed obtained silica-alumina gel; In silica-alumina gel, material mol ratio is 1.0 ~ 6.5Na
2o:Al
2o
3: 5.0 ~ 18SiO
2: 100 ~ 280H
2o, the wherein Al of directed agents
2o
3account for Al
2o
30.01 ~ 15 % by weight of total amount;
(3) by silica-alumina gel crystallization at 80 ~ 140 DEG C; Crystallization 0.1 ~ 80 hour;
(4) add superoxide in the Crystallized Silicon alumina gel obtained in (3), make 0 in superoxide
2 2-with the Al in gel
2o
3mol ratio be 0.05-20, then continue to obtain for crystallization 5-20 hour.
In said silica-alumina gel, material mol ratio is 1.4 ~ 4.6Na
2o:Al
2o
3: 6.5 ~ 12SiO
2: 140 ~ 240H
2o, the wherein Al of directed agents
2o
3account for Al
2o
30.1 ~ 10 % by weight of total amount.
In method provided by the present invention, step (1) said directed agents can be prepared by the various methods preparing NaY molecular sieve directed agents in prior art, but preferably prepares according to the customary preparation methods of the industrial NaY directed agents generally adopted at present.Such as according to USP3,639,099, USP3,671,191 and USP4,166, prepared by method disclosed in 099, to obtaining stay-in-grade product, technology and equipment can be kept not do larger change simultaneously.Crystallization director used in present method is according to industrial ordinary method, by water glass, sodium metaaluminate 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, after stirring, obtains at 15-70 DEG C for aging 0.5 ~ 48 hour.
In method provided by the present invention, in gel, add peralcohol in step 4 can be hydrogen peroxide, sodium peroxide, or one or more mixtures in Potassium peroxide.Afterwards mixture gel is continued crystallization and obtain zeolite product.
In method provided by the present invention, step (2) said sodium aluminate is sodium metaaluminate; Said acid aluminium salt is Tai-Ace S 150, aluminum chloride or aluminum nitrate, wherein preferably Tai-Ace S 150; Sodium aluminate synthesizes the Al of material together with the aluminium in acid aluminium salt and directed agents as NaY
2o
3source, the silicon in water glass and directed agents synthesizes the SiO of material together as NaY
2source; Acidic aluminum source can be used to the sodium aluminate of alkalescence the basicity regulating total material, and the ratio of the two requires to decide according to the basicity of total material.
According to method provided by the invention, can under the prerequisite substantially not changing existing production technique, do not add any organic or inorganic template, without aftertreatment modifying process repeatedly, directly can prepare the Y zeolite of high silica alumina ratio in the short period of time yet.Compared with ordinary method, under the condition of identical molar ratio, obviously can shorten crystallization time, the silica alumina ratio of the finished product can be increased to 5.5 simultaneously, generally more than 5.8, the product obtained is the small crystal grain molecular sieve of 200-300nm.
Accompanying drawing explanation
Fig. 1 embodiment 2 gained NaY molecular sieve electron microscope picture.
Embodiment
The following examples are used for that the present invention will be further described, but not thereby limiting the invention.
Embodiment 1
Get 81.50 grams of water glass (Red Star water glass plant, Beijing product, SiO
2content is 28.08 heavy %, modulus 3.28), add 80.16 grams of high alkali deflection aluminium acid sodiums (Shandong Aluminium Industrial Corp's product, Al
2o
3content is 3.16 heavy %, Na
2o content is 21.11 heavy %), then add 14 grams of deionized waters, after mixing at 50 DEG C aging 5 hours, make directed agents.Get 235 grams of water glass, under stirring, add 83.58 grams of high alkali deflection aluminium acid sodiums, 56.63 grams of above-mentioned directed agents, 183.24 grams of alum liquors (China Changcheng Aluminium Industry Co's product, Al successively
2o
3content is 7.1 heavy %), and 70 grams of water, mix, obtained mixture gel.
Loaded in tetrafluoroethylene bottle by mixture gel, at 100 DEG C, crystallization is after 16 hours, adds 20 grams of hydrogen peroxide (Beijing Chemical Plant, H in gelling system
2o
2content is 30 heavy %) in be uniformly mixed, obtained homogeneous gel, loads in tetrafluoroethylene bottle and to continue at 100 DEG C crystallization 24 hours, then filter, wash, dry NaY molecular sieve product 30.25 grams, records its degree of crystallinity 95%, silica alumina ratio 5.91.
Comparative example 1
Each raw material sources are with embodiment 1.Get 81.50 grams of water glass, add 80.16 grams of high alkali deflection aluminium acid sodiums, then add 14 grams of deionized waters, after mixing at 50 DEG C aging 5 hours, make directed agents.Get 235 grams of water glass, 72.50 grams of high alkali deflection aluminium acid sodiums, 56.63 grams of above-mentioned directed agents, 188.24 grams of alum liquors are added successively under stirring, and 70 grams of water, mix obtained gel 622.37 grams, load in tetrafluoroethylene bottle, crystallization 40 hours at 100 DEG C, then filter, wash, dry NaY molecular sieve product 79 grams, record its degree of crystallinity 77%, silica alumina ratio 5.22.
Comparative example 2
Each raw material sources are with embodiment 1.Get 81.50 grams of water glass, add 80.16 grams of high alkali deflection aluminium acid sodiums, then add 14 grams of deionized waters, after mixing at 50 DEG C aging 5 hours, make directed agents.Get 253.66 grams of water glass, 85.78 grams of high alkali deflection aluminium acid sodiums, 56.63 grams of above-mentioned directed agents, 199.52 grams of alum liquors are added successively under stirring, and 92.35 grams of water, mix obtained gel 687.94 grams, load in tetrafluoroethylene bottle, crystallization 40 hours at 100 DEG C, then filter, wash, dry NaY molecular sieve product 100.07 grams, record its degree of crystallinity 80%, silica alumina ratio 5.18.
Embodiment 2
Each raw material sources are with embodiment 1.Get 81.50 grams of water glass, add 80.16 grams of high alkali deflection aluminium acid sodiums, then add 14 grams of deionized waters, after mixing at 50 DEG C aging 5 hours, make directed agents.Get 270 grams of water glass, under stirring, add 83.58 grams of high alkali deflection aluminium acid sodiums, 56.63 grams of above-mentioned directed agents, 183.24 grams of alum liquors successively, and 70 grams of water, mix, obtained gel.
To obtain gel to load in tetrafluoroethylene bottle, at 100 DEG C, crystallization is after 26 hours, adds 50 grams of hydrogen peroxide (Beijing Chemical Plant, H in gelling system
2o
2content is 30 heavy %) in be uniformly mixed, load in tetrafluoroethylene bottle and to continue at 100 DEG C crystallization 26 hours, then filter, wash, dry NaY molecular sieve product 31.95 grams, record its degree of crystallinity 99%, silica alumina ratio 6.12, zeolite crystal is about 300nm.Shown in following scanning electron microscope (SEM) photograph:
Comparative example 3
Each raw material sources are with embodiment 1.Get 81.50 grams of water glass, add 80.16 grams of high alkali deflection aluminium acid sodiums, then add 14 grams of deionized waters, after mixing at 50 DEG C aging 5 hours, make directed agents.Get 278 grams of water glass, 70 grams of high alkali deflection aluminium acid sodiums, 56.63 grams of above-mentioned directed agents, 196 grams of alum liquors are added successively under stirring, and 70 grams of water, mix, obtained gel 670.63 grams, load in tetrafluoroethylene bottle, crystallization 122 hours at 100 DEG C, then filter, wash, dry NaY molecular sieve product 103.21 grams, record its degree of crystallinity 79%, silica alumina ratio 5.30.
Claims (4)
1. a synthetic method for NaY molecular sieve, is characterized in that:
(1) by water glass, sodium metaaluminate and deionized water according to 11 ~ 18Na
2o:Al
2o
3: 11 ~ 18SiO
2: 200 ~ 380H
2the mixed in molar ratio of O, after stirring, obtains crystallization director in aging 0.5 ~ 48 hour at 15-70 DEG C;
(2) crystallization director, water glass, acid aluminium salt and sodium aluminate solution are mixed obtained silica-alumina gel; In silica-alumina gel, material mol ratio is 1.0 ~ 6.5Na
2o:Al
2o
3: 5.0 ~ 18SiO
2: 100 ~ 280H
2o, the wherein Al of directed agents
2o
3account for Al
2o
30.01 ~ 15 % by weight of total amount;
(3) by silica-alumina gel crystallization at 80 ~ 140 DEG C; Crystallization 0.1 ~ 80 hour;
(4) add superoxide in the Crystallized Silicon alumina gel obtained in (3), make 0 in superoxide
2 2-with the Al in gel
2o
3mol ratio be 0.05-20, then continue to obtain for crystallization 5-20 hour.
2. according to the synthetic method of NaY molecular sieve according to claim 1, it is characterized in that: in said silica-alumina gel, material mol ratio is 1.4 ~ 4.6Na
2o:Al
2o
3: 6.5 ~ 12SiO
2: 140 ~ 240H
2o, the wherein Al of directed agents
2o
3account for Al
2o
30.1 ~ 10 % by weight of total amount.
3. according to the synthetic method of NaY molecular sieve according to claim 1, it is characterized in that: the superoxide added in step (4) is hydrogen peroxide, sodium peroxide, or one or more mixtures in Potassium peroxide.
4. according to the synthetic method of NaY molecular sieve according to claim 1, it is characterized in that: step (1) said sodium aluminate is sodium metaaluminate, said acid aluminium salt is one or more mixtures in Tai-Ace S 150, aluminum chloride or aluminum nitrate.
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| CN114655965B (en) * | 2020-12-23 | 2023-10-10 | 中国石油化工股份有限公司 | Method for preparing small-grain NaY |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1785808A (en) * | 2004-12-09 | 2006-06-14 | 中国石油天然气股份有限公司 | Preparation method of high silicon aluminium ratio small crystal NaY molecular sieve |
| CN1789125A (en) * | 2004-12-15 | 2006-06-21 | 中国石油化工股份有限公司 | Small crystal grain molecular sieve preparation method |
| CN101767799A (en) * | 2008-12-31 | 2010-07-07 | 中国石油化工股份有限公司 | Method for synthesizing high-silicon small grain NaY molecular sieve |
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2012
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1785808A (en) * | 2004-12-09 | 2006-06-14 | 中国石油天然气股份有限公司 | Preparation method of high silicon aluminium ratio small crystal NaY molecular sieve |
| CN1789125A (en) * | 2004-12-15 | 2006-06-21 | 中国石油化工股份有限公司 | Small crystal grain molecular sieve preparation method |
| CN101767799A (en) * | 2008-12-31 | 2010-07-07 | 中国石油化工股份有限公司 | Method for synthesizing high-silicon small grain NaY molecular sieve |
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