CN110856819B - Surface aluminum-rich molecular sieve, preparation method and application thereof, isomerization reaction catalyst and application thereof - Google Patents
Surface aluminum-rich molecular sieve, preparation method and application thereof, isomerization reaction catalyst and application thereof Download PDFInfo
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- 239000002808 molecular sieve Substances 0.000 title claims abstract description 113
- 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 113
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 title claims abstract description 37
- 229910052782 aluminium Inorganic materials 0.000 title claims abstract description 36
- 238000006317 isomerization reaction Methods 0.000 title claims abstract description 28
- 238000002360 preparation method Methods 0.000 title abstract description 9
- 239000007809 chemical reaction catalyst Substances 0.000 title description 7
- 150000001335 aliphatic alkanes Chemical class 0.000 claims abstract description 4
- 238000002425 crystallisation Methods 0.000 claims description 65
- 230000008025 crystallization Effects 0.000 claims description 65
- 239000000499 gel Substances 0.000 claims description 62
- 239000002243 precursor Substances 0.000 claims description 60
- 238000000034 method Methods 0.000 claims description 38
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 27
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 23
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 18
- 229910052710 silicon Inorganic materials 0.000 claims description 18
- 239000010703 silicon Substances 0.000 claims description 18
- CSDREXVUYHZDNP-UHFFFAOYSA-N alumanylidynesilicon Chemical compound [Al].[Si] CSDREXVUYHZDNP-UHFFFAOYSA-N 0.000 claims description 17
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 17
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 14
- 239000003054 catalyst Substances 0.000 claims description 13
- 239000000377 silicon dioxide Substances 0.000 claims description 12
- 229910018072 Al 2 O 3 Inorganic materials 0.000 claims description 10
- 238000002156 mixing Methods 0.000 claims description 10
- RMAQACBXLXPBSY-UHFFFAOYSA-N silicic acid Chemical group O[Si](O)(O)O RMAQACBXLXPBSY-UHFFFAOYSA-N 0.000 claims description 10
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical group 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 claims description 8
- 229910052708 sodium Inorganic materials 0.000 claims description 8
- 239000011734 sodium Substances 0.000 claims description 8
- 239000003795 chemical substances by application Substances 0.000 claims description 6
- 229910004298 SiO 2 Inorganic materials 0.000 claims description 5
- 239000002585 base Substances 0.000 claims description 5
- 229910052751 metal Inorganic materials 0.000 claims description 5
- 239000002184 metal Substances 0.000 claims description 5
- 239000002245 particle Substances 0.000 claims description 5
- 239000003513 alkali Substances 0.000 claims description 4
- 239000011230 binding agent Substances 0.000 claims description 4
- 239000012188 paraffin wax Substances 0.000 claims description 2
- 230000003197 catalytic effect Effects 0.000 abstract description 11
- 239000002253 acid Substances 0.000 abstract description 8
- 238000006555 catalytic reaction Methods 0.000 abstract description 4
- 239000000047 product Substances 0.000 description 22
- 238000006243 chemical reaction Methods 0.000 description 20
- 238000003756 stirring Methods 0.000 description 15
- 238000012360 testing method Methods 0.000 description 15
- QGZKDVFQNNGYKY-UHFFFAOYSA-O ammonium group Chemical group [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 description 12
- 230000015572 biosynthetic process Effects 0.000 description 9
- 238000005406 washing Methods 0.000 description 9
- 239000011148 porous material Substances 0.000 description 8
- 238000003786 synthesis reaction Methods 0.000 description 8
- 230000000052 comparative effect Effects 0.000 description 6
- 238000009826 distribution Methods 0.000 description 6
- 238000001035 drying Methods 0.000 description 6
- 230000000694 effects Effects 0.000 description 6
- 229940005740 hexametaphosphate Drugs 0.000 description 6
- 229950006187 hexamethonium bromide Drugs 0.000 description 6
- FAPSXSAPXXJTOU-UHFFFAOYSA-L trimethyl-[6-(trimethylazaniumyl)hexyl]azanium;dibromide Chemical compound [Br-].[Br-].C[N+](C)(C)CCCCCC[N+](C)(C)C FAPSXSAPXXJTOU-UHFFFAOYSA-L 0.000 description 6
- 238000001914 filtration Methods 0.000 description 5
- NAQMVNRVTILPCV-UHFFFAOYSA-N hexane-1,6-diamine Chemical compound NCCCCCCN NAQMVNRVTILPCV-UHFFFAOYSA-N 0.000 description 5
- 238000004458 analytical method Methods 0.000 description 4
- 229910052799 carbon Inorganic materials 0.000 description 4
- DCAYPVUWAIABOU-UHFFFAOYSA-N hexadecane Chemical compound CCCCCCCCCCCCCCCC DCAYPVUWAIABOU-UHFFFAOYSA-N 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- 238000007789 sealing Methods 0.000 description 4
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 3
- 229910021536 Zeolite Inorganic materials 0.000 description 3
- 150000004645 aluminates Chemical class 0.000 description 3
- 238000001816 cooling Methods 0.000 description 3
- 239000013078 crystal Substances 0.000 description 3
- HNPSIPDUKPIQMN-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Al]O[Al]=O HNPSIPDUKPIQMN-UHFFFAOYSA-N 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- JRZJOMJEPLMPRA-UHFFFAOYSA-N olefin Natural products CCCCCCCC=C JRZJOMJEPLMPRA-UHFFFAOYSA-N 0.000 description 3
- 230000003068 static effect Effects 0.000 description 3
- 238000004846 x-ray emission Methods 0.000 description 3
- 239000010457 zeolite Substances 0.000 description 3
- BANXPJUEBPWEOT-UHFFFAOYSA-N 2-methyl-Pentadecane Chemical compound CCCCCCCCCCCCCC(C)C BANXPJUEBPWEOT-UHFFFAOYSA-N 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 239000004215 Carbon black (E152) Substances 0.000 description 2
- JUJWROOIHBZHMG-UHFFFAOYSA-N Pyridine Chemical compound C1=CC=NC=C1 JUJWROOIHBZHMG-UHFFFAOYSA-N 0.000 description 2
- -1 ZSM-5 Chemical compound 0.000 description 2
- 239000004411 aluminium Substances 0.000 description 2
- VSCWAEJMTAWNJL-UHFFFAOYSA-K aluminium trichloride Chemical compound Cl[Al](Cl)Cl VSCWAEJMTAWNJL-UHFFFAOYSA-K 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 2
- 238000012512 characterization method Methods 0.000 description 2
- 238000005336 cracking Methods 0.000 description 2
- 238000003795 desorption Methods 0.000 description 2
- 239000012467 final product Substances 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 229930195733 hydrocarbon Natural products 0.000 description 2
- 150000002430 hydrocarbons Chemical class 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 239000003921 oil Substances 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 238000001308 synthesis method Methods 0.000 description 2
- 230000002194 synthesizing effect Effects 0.000 description 2
- PWGJDPKCLMLPJW-UHFFFAOYSA-N 1,8-diaminooctane Chemical compound NCCCCCCCCN PWGJDPKCLMLPJW-UHFFFAOYSA-N 0.000 description 1
- 229940043268 2,2,4,4,6,8,8-heptamethylnonane Drugs 0.000 description 1
- PAWQVTBBRAZDMG-UHFFFAOYSA-N 2-(3-bromo-2-fluorophenyl)acetic acid Chemical compound OC(=O)CC1=CC=CC(Br)=C1F PAWQVTBBRAZDMG-UHFFFAOYSA-N 0.000 description 1
- VZJFGSRCJCXDSG-UHFFFAOYSA-N Hexamethonium Chemical compound C[N+](C)(C)CCCCCC[N+](C)(C)C VZJFGSRCJCXDSG-UHFFFAOYSA-N 0.000 description 1
- 239000004115 Sodium Silicate Substances 0.000 description 1
- BOTDANWDWHJENH-UHFFFAOYSA-N Tetraethyl orthosilicate Chemical compound CCO[Si](OCC)(OCC)OCC BOTDANWDWHJENH-UHFFFAOYSA-N 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 229910000272 alkali metal oxide Inorganic materials 0.000 description 1
- 150000001340 alkali metals Chemical class 0.000 description 1
- 229910001860 alkaline earth metal hydroxide Inorganic materials 0.000 description 1
- 150000001336 alkenes Chemical class 0.000 description 1
- 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 1
- 239000002199 base oil Substances 0.000 description 1
- 238000001354 calcination Methods 0.000 description 1
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 description 1
- 239000000920 calcium hydroxide Substances 0.000 description 1
- 229910001861 calcium hydroxide Inorganic materials 0.000 description 1
- 150000001721 carbon Chemical group 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000004132 cross linking Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 239000008367 deionised water Substances 0.000 description 1
- 229910021641 deionized water Inorganic materials 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- SNRUBQQJIBEYMU-UHFFFAOYSA-N dodecane Chemical compound CCCCCCCCCCCC SNRUBQQJIBEYMU-UHFFFAOYSA-N 0.000 description 1
- 238000013401 experimental design Methods 0.000 description 1
- 239000000706 filtrate Substances 0.000 description 1
- 238000001640 fractional crystallisation Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 229950002932 hexamethonium Drugs 0.000 description 1
- 238000005216 hydrothermal crystallization Methods 0.000 description 1
- KUVMKLCGXIYSNH-UHFFFAOYSA-N isopentadecane Natural products CCCCCCCCCCCCC(C)C KUVMKLCGXIYSNH-UHFFFAOYSA-N 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000010687 lubricating oil Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229940094933 n-dodecane Drugs 0.000 description 1
- 239000003345 natural gas Substances 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 229910052763 palladium Inorganic materials 0.000 description 1
- 229910052697 platinum Inorganic materials 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- UMJSCPRVCHMLSP-UHFFFAOYSA-N pyridine Natural products COC1=CC=CN=C1 UMJSCPRVCHMLSP-UHFFFAOYSA-N 0.000 description 1
- 239000000376 reactant Substances 0.000 description 1
- 230000008929 regeneration Effects 0.000 description 1
- 238000011069 regeneration method Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 238000007086 side reaction Methods 0.000 description 1
- 239000000741 silica gel Substances 0.000 description 1
- 229910002027 silica gel Inorganic materials 0.000 description 1
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 description 1
- 229910052911 sodium silicate Inorganic materials 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 238000003828 vacuum filtration Methods 0.000 description 1
- 239000001993 wax Substances 0.000 description 1
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J29/00—Catalysts comprising molecular sieves
- B01J29/04—Catalysts comprising molecular sieves having base-exchange properties, e.g. crystalline zeolites
- B01J29/06—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof
- B01J29/70—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof of types characterised by their specific structure not provided for in groups B01J29/08 - B01J29/65
- B01J29/703—MRE-type, e.g. ZSM-48
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
- B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
- B01J35/61—Surface area
- B01J35/615—100-500 m2/g
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
- B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
- B01J35/61—Surface area
- B01J35/617—500-1000 m2/g
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
- B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
- B01J35/64—Pore diameter
- B01J35/643—Pore diameter less than 2 nm
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/0009—Use of binding agents; Moulding; Pressing; Powdering; Granulating; Addition of materials ameliorating the mechanical properties of the product catalyst
- B01J37/0018—Addition of a binding agent or of material, later completely removed among others as result of heat treatment, leaching or washing,(e.g. forming of pores; protective layer, desintegrating by heat)
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C5/00—Preparation of hydrocarbons from hydrocarbons containing the same number of carbon atoms
- C07C5/22—Preparation of hydrocarbons from hydrocarbons containing the same number of carbon atoms by isomerisation
- C07C5/27—Rearrangement of carbon atoms in the hydrocarbon skeleton
- C07C5/2729—Changing the branching point of an open chain or the point of substitution on a ring
- C07C5/2732—Catalytic processes
- C07C5/2737—Catalytic processes with crystalline alumino-silicates, e.g. molecular sieves
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C5/00—Preparation of hydrocarbons from hydrocarbons containing the same number of carbon atoms
- C07C5/22—Preparation of hydrocarbons from hydrocarbons containing the same number of carbon atoms by isomerisation
- C07C5/27—Rearrangement of carbon atoms in the hydrocarbon skeleton
- C07C5/2767—Changing the number of side-chains
- C07C5/277—Catalytic processes
- C07C5/2775—Catalytic processes with crystalline alumino-silicates, e.g. molecular sieves
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J2229/00—Aspects of molecular sieve catalysts not covered by B01J29/00
- B01J2229/10—After treatment, characterised by the effect to be obtained
- B01J2229/18—After treatment, characterised by the effect to be obtained to introduce other elements into or onto the molecular sieve itself
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- Chemical Kinetics & Catalysis (AREA)
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Abstract
The invention relates to the field of molecular sieves, and discloses a preparation method of a molecular sieve with an aluminum-rich surface. The obtained molecular sieve has high crystallinity, effective acid centers are intensively distributed on the outer surface, and the molecular sieve shows high catalytic activity and high catalytic selectivity in long-chain alkane isomerization catalytic reaction.
Description
Technical Field
The invention relates to the field of molecular sieves, in particular to a molecular sieve with an aluminum-rich surface, a preparation method and application thereof, an isomerization catalyst and application thereof.
Background
Molecular sieves are commonly used as catalysts or catalyst supports due to their pore structure. Of these, molecular sieves such as ZSM-5, ZSM-12, ZSM-22, ZSM-23, ZSM-48 and SSZ-32 are used in larger amounts. ZSM-48 is a kind of high silicon zeolite, belonging to orthorhombic system structure, having 10-membered open pore non-through interlaced linear pore canal, the pore canals are connected by 5-membered ring, the pore diameter is 0.53nm x 0.56 nm. Generally, pure silicon ZSM-48 molecular sieve has good selectivity of low carbon olefin in the reaction of preparing olefin from synthesis gas, and the ratio of silicon to aluminum is low (SiO 2 /Al 2 O 3 ) The ZSM-48 molecular sieve has good isomerization cracking catalytic performance.
"Synthesis and characterization of high-silica zeolite ZSM-48" (Natural gas chemical, 1993, 18 (1): 8-12) discloses a method for preparing high-silica zeolite ZSM-48 by using 1, 6-hexamethylenediamine as a structure directing agent through hydrothermal crystallization, wherein the used raw materials are silica sol, NaOH, 1, 6-hexamethylenediamine and deionized water. Adding the reactants into a 100mL stainless steel high-pressure synthesis kettle according to a certain proportion and sequence, stirring for 10-15min, sealing, standing at 185 ℃ for crystallization until crystallization is completed, wherein the crystallization time is selected according to the temperature. After separation, washing and drying, NaZSM-48 raw powder is obtained, but the synthesis and the application of the ZSM-48 containing aluminum are not involved in the text. The synthesized ZSM-48 molecular sieve with high silica-alumina ratio has large and aggregated crystal grains, large crystal grain size and poor catalyst performance; high water content and low single-kettle yield.
The synthesis and characterization of the ZSM-48 molecular sieve with the low silica alumina ratio (modern chemical industry, 2014, 34, 3:97-102) discloses a synthesis method of the ZSM-48 molecular sieve with the low silica alumina ratio. Through orthogonal experimental design, the influence of various factors on the synthesis of the ZSM-48 is researched, the synthesis system of the ZSM-48 molecular sieve with the low silica-alumina ratio is optimized by changing the using amounts of the template agent, the silicon source, the alkali source and the water, and the ZSM-48 molecular sieve with the silica-alumina ratio as low as 56.7 is finally prepared, however, the test result shows that the ZSM-48 with the low silica-alumina ratio is in a rod-shaped and sheet-shaped conglomerate form and has lower relative crystallinity.
Applicants have found that high silica ZSM-48 sieves have too low activity in isomerization catalysis, while low silica-alumina ratio ZSM-48 sieves have poor isomerization selectivity despite improved catalytic activity. At present, a plurality of synthesis methods of ZSM-48 molecular sieves are reported in documents, but the obtained molecular sieves cannot realize the joint optimization of catalytic activity and isomeric selectivity, namely, higher catalytic activity is obtained and higher selectivity is ensured.
The applicant has also found that during the isomerization of long paraffins, the framework aluminium content on the molecular sieve, corresponding to the framework acidity, determines the catalytic activity. On the premise of no change of metal functions, the addition of acid functions (low silicon-aluminum ratio) is beneficial to improving the conversion rate of raw materials but not beneficial to isomerization rate; reducing the acid function (high silica to alumina ratio) reduces the undesirable cracking reactions, but at the same time reduces the feed conversion and reduces the catalytic activity. The molecular sieve synthesized by the conventional method usually cannot compromise the activity and the selectivity, which is mainly because the acid center distribution of the molecular sieve synthesized by one-time crystallization is unreasonable, and the inner surface of the molecular sieve contains aluminum acid sites, so that the isomeric products are easy to further crack and lose.
Therefore, there is a need for a method for preparing a molecular sieve having sufficient aluminate sites on the surface and no or less framework aluminate sites on the inner surface, so as to avoid or reduce side reactions caused by the framework aluminate sites on the inner surface of the molecular sieve while ensuring the catalytic activity of the surface.
Disclosure of Invention
The invention aims to solve the problem that high activity and high isomerization selectivity cannot be simultaneously obtained when a molecular sieve is used for long-chain alkane isomerization conversion in the prior art, and provides a surface aluminum-rich molecular sieve, a preparation method and application thereof, an isomerization reaction catalyst and application thereof.
In order to achieve the above object, a first aspect of the present invention provides a method for preparing a surface aluminum-rich molecular sieve, the method comprising:
(1) preparing a precursor gel A, B, wherein the silicon-aluminum ratio of the precursor gel A is 40-100, the silicon-aluminum ratio of the precursor gel B is 100-400, and the silicon-aluminum ratios of the precursor gel A and the precursor gel B are different;
(2) respectively carrying out first-step crystallization on the precursor gels A, B;
(3) respectively preparing a first-step crystallization product from the precursor gel A, B according to a mass ratio of 1: (3-50) mixing and carrying out second-step crystallization to finally prepare the surface aluminum-rich molecular sieve.
In a second aspect, the present invention provides a surface aluminum-rich molecular sieve produced by the process of the first aspect of the present invention.
In a third aspect, the invention provides the use of a molecular sieve according to the second aspect of the invention in a catalytic reaction.
In a fourth aspect, the present invention provides an isomerisation reaction catalyst comprising a binder, a metal active component and a molecular sieve according to the second aspect of the invention.
In a fifth aspect, the present invention provides the use of an isomerisation reaction catalyst according to the fourth aspect of the invention in an isomerisation reaction of a hydrocarbon.
The invention prepares two molecular sieve precursor gels with different silicon-aluminum ratios, the silicon-aluminum ratio is in the range of 40-400, and the molecular sieve precursor gels are respectively crystallized for a period of time through fractional crystallization to obtain semi-crystallized or completely crystallized products, and then the semi-crystallized or completely crystallized products are mixed according to a certain proportion and are crystallized for a period of time again to obtain the molecular sieve with controllable acid distribution and gradient distribution of aluminum element from outside to inside.
The method can be used for synthesizing the ZSM-48 molecular sieve and also can be used for synthesizing the ZSM-5, ZSM-12, ZSM-22, ZSM-23, ZSM-48 and SSZ-32 molecular sieves, the obtained molecular sieve not only has high crystallinity, but also has effective acid centers which are intensively distributed on the outer surface, thereby avoiding the adverse effect caused by the acid centers on the inner surface, and having higher isomeric selectivity while keeping high catalytic activity. The surface aluminum-rich molecular sieve has good application prospect in the fields of preparing low-carbon olefin from synthesis gas, isomerizing normal paraffin and preparing lubricating oil base oil and the like from wax oil through hydroisomerization.
Drawings
FIG. 1 is a Transmission Electron Microscope (TEM) section analysis of the molecular sieve described in example 2.
FIG. 2 is a TEM section analysis of the molecular sieve described in example 2 showing the Si/Al ratio over a surface thickness range of 200 nm.
Detailed Description
The endpoints of the ranges and any values disclosed herein are not limited to the precise range or value, and such ranges or values should be understood to encompass values close to those ranges or values. For ranges of values, between the endpoints of each of the ranges and the individual points, and between the individual points may be combined with each other to give one or more new ranges of values, and these ranges of values should be considered as specifically disclosed herein.
The invention provides a preparation method of a surface aluminum-rich molecular sieve in a first aspect, which comprises the following steps:
(1) preparing a precursor gel A, B, wherein the silicon-aluminum ratio of the precursor gel A is 40-100, the silicon-aluminum ratio of the precursor gel B is 100-400, and the silicon-aluminum ratios of the precursor gel A and the precursor gel B are different;
(2) respectively carrying out first-step crystallization on the precursor gels A, B;
(3) respectively preparing a first-step crystallization product from the precursor gel A, B according to a mass ratio of 1: (3-50) mixing and carrying out second-step crystallization to finally prepare the surface aluminum-rich molecular sieve.
As used herein, the Si/Al ratio refers to the molar ratio of silica to alumina.
In the present invention, the silica-alumina ratio of the precursor gel a may be any value in the range of 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95 and 100 and any two of the above values, and preferably, the silica-alumina ratio of the precursor gel a is 50 to 100.
In the present invention, the silica/alumina ratio of the precursor gel B can be any value in the range of 105, 110, 120, 150, 170, 200, 230, 250, 270, 300, 320, 350, 380 and 400 and any two of the above values, preferably, the silica/alumina ratio of the precursor gel B is 150-350, and more preferably 150-300.
In the present invention, in step (1), the precursor gel A, B is prepared from a template, a silicon source, an aluminum source, water and sodium hydroxide.
In the present invention, in the precursor gel a, the molar ratio of the silicon source, the aluminum source, the water, the alkali and the template agent is 1: (0.01-0.025): (10-40): (0.11-0.19): (0.0175 to 0.0215), preferably 1: (0.015-0.025): (20-40): (0.14-0.19): (0.0195 to 0.0215), more preferably 1: (0.015-0.02): (20-30): (0.15-0.17): (0.0195-0.0215). The silicon source is SiO 2 The aluminum source is calculated as Al 2 O 3 Calculated as OH, the base - And (6) counting.
In the precursor gel B, the silicon source, the aluminum source, the water, the alkali and the templateThe molar ratio of the agents is 1: (0.0025-0.01): (10-40): (0.11-0.19): (0.0175 to 0.0215), preferably 1: (0.0025-0.008): (10-20): (0.11-0.15): (0.0175-0.0195), more preferably 1: (0.0035-0.005): (10-20): (0.13-0.15): (0.0175-0.0195). The silicon source is SiO 2 The aluminum source is calculated as Al 2 O 3 Calculated as OH, the base - And (6) counting.
In the present invention, the silicon source and the aluminum source used can be selected according to the prior art, for example, the silicon source can be silica sol, solid silica gel, sodium silicate, tetraethyl silicate, etc., and the aluminum source can be sodium metaaluminate, aluminum sulfate, aluminum chloride, aluminum sol, etc. According to a preferred embodiment, the silicon source is silica sol and the aluminium source is sodium metaaluminate. The content of silica in the silica sol can be selected according to the actual need, for example, from 20 to 40 wt%.
In the present invention, the base may be selected according to the prior art. Preferably, the base is an alkali metal and/or alkaline earth metal hydroxide, such as at least one of sodium hydroxide, potassium hydroxide and calcium hydroxide.
In the present invention, the template may be selected according to the molecular sieve to be prepared. In one embodiment of the present invention, the template is selected from at least one of 1, 6-hexanediamine, 1, 8-octanediamine and hexamethonium bromide, and the molecular sieve prepared using the above template is a ZSM-48 molecular sieve.
In the present invention, in step (2), the first crystallization of precursor gel a is performed for a period of time to obtain a gel state in an amorphous state before the formation of a crystalline phase, so that the crystallization conditions may be adjusted according to actual operating conditions, for example, the conditions for the first crystallization of precursor gel a include: the temperature is 150-190 ℃, and preferably 150-160 ℃; the time is 3 to 120 hours, preferably 4 to 24 hours, more preferably 8 to 16 hours.
In the present invention, in the step (2), the first crystallization process of the precursor gel B is performed for crystallization for a certain period of time to obtain a gel state forming a crystal phase, so that the crystallization conditions can be adjusted according to actual operating conditions, for example, the conditions of the first crystallization of the precursor gel B include: the temperature is 150-190 ℃, and preferably 150-160 ℃; the time is 3 to 120 hours, preferably 12 to 48 hours, more preferably 16 to 32 hours.
In the invention, in step (3), the first step crystallization products of precursor gel A, B are mixed according to a certain mass ratio for the second step crystallization. The mixing ratio of the first-step crystallization product of precursor gel A, B can be adjusted according to the silicon-aluminum ratio of A, B, the condition of the first-step crystallization, and the like, and for example, may be 1:3, 1:5, 1:10, 1:15, 1:20, 1:25, 1:30, 1:35, 1:40, 1:45, and 1:50, and preferably, the mass ratio of the first-step crystallization product of precursor gel A, B is 1: (5-30); more preferably 1: (5-20).
In the invention, the first step crystallization product of the precursor gel A, B is mixed according to the proportion and then is subjected to the second step crystallization. The conditions of the second step crystallization include: the temperature is 150-190 ℃, preferably 160-170 ℃; the time is 6-48h, preferably 8-12 h.
In the present invention, the first crystallization and the second crystallization are performed in a reactor, which may be, for example, a reaction vessel or a crystallization vessel. The first and second crystallization steps may be selected from dynamic or static crystallization, respectively. In the invention, the static crystallization refers to that no stirring process or mixing process similar to stirring exists in the system in the crystallization process; the dynamic crystallization refers to the condition that a stirring process or a mixing process similar to stirring is always existed in the system in the crystallization process.
In the present invention, it is preferable that the first crystallization step of precursor gel A, B be dynamic crystallization. Also, the second crystallization step of the mixture of the first crystallization step products of the precursor gel A, B is a static crystallization. During the first dynamic crystallization step of the precursor gel A, B, the stirring speed can be adjusted as required, for example, at 100-.
In the invention, after the second step of crystallization, the obtained product is separated, washed, dried, ammonium-exchanged and roasted to prepare the molecular sieve with aluminum-enriched surface. The specific operations of separating, washing, drying, ammonium exchange and roasting can be selected according to the prior art, for example, the separating and washing adopts a vacuum filtration method or a centrifugal washing method until the pH value of the filtrate is reduced to below 10; ammonium nitrate solution with the concentration of 1mol/L is adopted for stirring treatment for 1h at the temperature of 80 ℃, and the steps of filtering and washing are repeated for 2-3 times; the calcination was carried out at 550 ℃ for 4h in an air atmosphere.
In a second aspect, the present invention provides a surface-enriched aluminum molecular sieve prepared by the method of the first aspect, wherein the molecular sieve can be any one of ZSM-5, ZSM-12, ZSM-22, ZSM-23, ZSM-48 or SSZ-32 molecular sieves.
According to one embodiment, the ZSM-48 molecular sieve is prepared by the method, the silicon-aluminum ratio of the whole molecular sieve is 150-300, and the silicon-aluminum ratio of the particle surface of the molecular sieve in the thickness of 50nm is 40-150, preferably 40-90. Here, the expression "within 50nm of the thickness of the particle surface" is to be understood as meaning a range of thicknesses which are 50nm from the particle surface.
According to one embodiment, the method produces a molecular sieve having a specific surface area of not less than 200m 2 Per g, preferably 200-1000m 2 (ii)/g; the aperture is 0.53-0.56 nm; pore volume of not less than 0.1cm 3 In terms of/g, preferably from 0.1 to 1cm 3 /g。
In the invention, the molecular sieve prepared by the method has higher crystallinity, and the crystallinity is more than 98%.
In a third aspect, the present invention provides the use of a molecular sieve according to the second aspect of the invention in a catalytic reaction.
In a fourth aspect, the present invention provides an isomerisation reaction catalyst comprising a molecular sieve according to the second aspect of the invention.
In one embodiment of the invention, the catalyst further comprises a binder and a metal active component, the metal active component being selected according to the prior art, for example one or more selected from Pt, Pd and Ni, and the binder being selected according to the prior art, for example alumina or silica.
In the present invention, the isomerization catalyst comprises the molecular sieve prepared by the method of the first aspect of the present invention, the molecular sieve has a high crystallinity (98% or more), and the distribution of aluminum element decreases in a gradient manner from the outside to the inside, and the structure and the composition are such that a high catalytic activity and a high isomerization selectivity can be simultaneously obtained in the isomerization reaction of long-chain alkane (carbon atom number of 10 or more, for example, n-dodecane or n-hexadecane).
In a fifth aspect, the present invention provides the use of an isomerisation reaction catalyst according to the fourth aspect of the invention in an isomerisation reaction of a hydrocarbon.
The present invention will be described in detail below by way of examples.
Example 1
(1) Dissolving 7.78g of hexamethonium bromide, 3.28g of sodium metaaluminate and 6g of sodium hydroxide in 540g of water to form a solution; 200g of silica sol (with the concentration of 30 wt%) is slowly added into the solution of the system under stirring and stirred uniformly to prepare a molecular sieve precursor gel A, wherein SiO is used 2 ：Al 2 O 3 ：H 2 O：OH - : the molar ratio of the ammonium hexametaphosphate to the ammonium hexametaphosphate is 1:0.02:30:0.15: 0.0215;
(2) 6.34g of hexamethonium bromide, 0.82g of sodium metaaluminate and 5.2g of sodium hydroxide were dissolved in 270g of water to form a solution; 200g of silica sol (with the concentration of 30 wt%) is slowly added into the solution of the system under stirring and stirred uniformly to prepare a molecular sieve precursor gel B, wherein SiO is used 2 ：Al 2 O 3 ：H 2 O：OH - : the molar ratio of the ammonium hexamethobromide is 1:0.005:15:0.13: 0.0175;
(3) putting the molecular sieve precursor gel A, B into different reaction kettles, sealing, and crystallizing for 12 hours by performing first-step crystallization on A at the temperature of 150 ℃ and the rotating speed of 500 rpm; b, performing first-step crystallization at 160 ℃ and at the rotating speed of 500rpm for 24 hours;
(4) cooling the reaction kettle to be below 100 ℃, then mixing A, B first-step crystallization products according to the mass ratio of 1:5, uniformly stirring, carrying out second-step crystallization at 170 ℃, statically crystallizing for 12 hours, filtering, washing, drying and carrying out ammonium exchange on the obtained product, roasting for 4 hours at 550 ℃, and obtaining the molecular sieve, wherein the crystallinity is 98%, and is marked as A1.
Example 2
The molecular sieve was prepared by the method described in example 1 except that A, B first-step crystallized product was mixed at a mass ratio of 1:10 and then second-step crystallized to finally obtain molecular sieve with a crystallinity of 99%, designated as a 2.
Example 3
The molecular sieve was prepared by the method described in example 1 except that A, B first-step crystallized product was mixed at a mass ratio of 1:20 and then second-step crystallized to finally obtain molecular sieve with a crystallinity of 98%, which was designated as A3.
Example 4
The molecular sieve was prepared by the method described in example 1 except that A, B first step crystallized product was mixed at a mass ratio of 1:30 and then second step crystallized to finally obtain molecular sieve with a crystallinity of 98%, which was designated as a 4.
Example 5
The molecular sieve was prepared by the method described in example 1 except that A, B first step crystallized product was mixed at a mass ratio of 1:50 and then second step crystallized to finally obtain molecular sieve with a crystallinity of 98%, which was designated as a 5.
Example 6
Molecular sieves were prepared as described in example 1, except that in step (4), A was subjected to a first crystallization step at 150 ℃ and 500rpm for 24h to finally obtain molecular sieves having a crystallinity of 98%, designated A6.
Comparative example 1
The molecular sieve was prepared as described in example 1, except that A, B crystallized product from the first step was mixed at a mass ratio of 1:80 to finally obtain the molecular sieve with a crystallinity of 96%, which is designated as D1.
Comparative example 2
Molecular sieves were prepared as described in example 1, except that the product of the first crystallization step of A, B was separately crystallized for 12h under the conditions of the second crystallization step described in example 1; and mixing the crystallized products according to the mass ratio of 1:5 to finally prepare the molecular sieve, wherein the crystallinity is 91 percent and is marked as D2.
Example 7
(1) Dissolving 7.78g of hexamethonium bromide, 1.64g of sodium metaaluminate and 6g of sodium hydroxide in 540g of water to form a solution; 200g of silica sol (with the concentration of 30 wt%) is slowly added into the solution of the system under stirring and stirred uniformly to prepare a molecular sieve precursor gel A, wherein SiO is used 2 ：Al 2 O 3 ：H 2 O：OH - : the molar ratio of the ammonium hexametaphosphate to the ammonium hexametaphosphate is 1:0.01:30:0.15: 0.0215;
(3) preparation of molecular Sieve precursor gel B according to the same procedure as in example 1, with SiO 2 ：Al 2 O 3 ：H 2 O：OH - : the molar ratio of the ammonium hexametaphosphate is 1:0.005:15:0.13: 0.0175;
(4) respectively putting the molecular sieve precursor gel A, B into a reaction kettle, sealing, performing first-step crystallization for 10 hours at 150 ℃ and 500rpm, and performing first-step crystallization for 24 hours at 160 ℃ and 500 rpm;
(5) cooling the reaction kettle to be below 100 ℃, mixing A, B first-step crystallization products according to the mass ratio of 1:10, uniformly stirring, statically crystallizing at 165 ℃ for 12 hours again, filtering, washing, drying and exchanging ammonium in the final product, roasting at 550 ℃ for 4 hours to obtain the molecular sieve, wherein the crystallinity is 98%, and is marked as A7.
Comparative example 3
The molecular sieve is prepared by referring to the method described in example 5, except that the molecular sieve precursor gel with the silica-alumina ratio of 162 is directly prepared, and is statically crystallized for 12 hours at 165 ℃, so that the final product is directly obtained, and the molecular sieve is obtained by filtering, washing, drying, ammonium exchange and roasting, and the crystallinity degree is 95%, and is marked as D3.
Example 8
(1) Dissolving 7.06g of hexamethonium bromide, 3.28g of sodium metaaluminate and 6g of sodium hydroxide in 540g of water to form a solution; 200g of silica sol (with the concentration of 30 wt%) is slowly added into the solution of the system under stirring and stirred uniformly to prepare a molecular sieve precursor gel A, wherein SiO is used 2 ：Al 2 O 3 ：H 2 O：OH - : moles of hexamethonium bromideThe molar ratio is 1:0.02:25:0.17: 0.0195;
(3) 6.34g of hexamethonium bromide, 0.41g of sodium metaaluminate and 5.2g of sodium hydroxide were dissolved in 270g of water to form a solution; 200g of silica sol (30 wt% in concentration) was slowly added to the solution of system (1) with stirring and stirred uniformly to prepare a molecular sieve precursor gel A in which SiO is used 2 ：Al 2 O 3 ：H 2 O：OH - : the molar ratio of the ammonium hexametaphosphate is 1:0.0025:20:0.15: 0.0195;
(4) respectively putting the molecular sieve precursor gel A, B into a reaction kettle, sealing, performing first-step crystallization for 15 hours at 150 ℃ and 500rpm, and performing first-step crystallization for 20 hours at 170 ℃ and 500 rpm;
(5) and (3) cooling, mixing A, B first-step crystallization products according to the mass ratio of 1:10, uniformly stirring, statically crystallizing at 170 ℃ for 12 hours again, filtering, washing, drying, performing ammonium cross-linking, and roasting at 550 ℃ for 4 hours to obtain the molecular sieve, wherein the crystallinity is 98%, and is marked as A8.
Test example
1. XRD test
XRD tests were carried out on the molecular sieves A1-A8 and D1-D3 obtained in examples 1-8 and comparative examples 1-3, respectively, and the tests showed that XRD characteristic peaks of all the samples were ascribed to MRE topology (spatial structure code of ZSM-48 molecular sieve), indicating that the molecular sieves A1-A8 and D1-D3 were both ZSM-48 molecular sieves, and the crystallinity of the molecular sieves A1-A8 was 98% or more.
2. X-ray fluorescence Spectroscopy (XRF) testing
The molecular sieves A1-A8 and D1-D3 obtained in examples 1-8 and comparative examples 1-3 were subjected to XRF testing, and elemental composition tests of the molecular sieves were examined, and the results are shown in Table 1 as a whole of the silicon to aluminum ratio.
TABLE 1
3. Distribution test of Al element
The molecular sieves A1-A8 and D1-D3 obtained in examples 1 to 8 and comparative examples 1 to 3 were examined by Transmission Electron Microscope (TEM) section analysis, and the distribution of Al element in the molecular sieves from the outside to the inside was examined, and the results are shown in Table 1 as the Si/Al ratio in the thickness of 50nm on the surface. The molecular sieve of example 2 is shown in a TEM section analysis and detection diagram in FIG. 1, and the molecular sieve of example 2 has a Si/Al ratio in a surface thickness range of 200nm in FIG. 2, and it can be seen from FIG. 2 that Al element in the molecular sieve is distributed in a gradient manner.
4. Specific surface area and pore volume test
The specific surface areas and pore volumes of the molecular sieves A1-A8 and D1-D3 were tested by a low temperature liquid nitrogen physical adsorption method, and the test results are shown in Table 1.
5. Testing of framework acidity
Taking a molecular sieve sample of 20mg, tabletting with diameter of 1.3cm, placing into an infrared test sample cell, and vacuumizing to 10% -3 Heating to 400 ℃ for 30min, adsorbing pyridine at room temperature, vacuumizing for desorption, reaching desorption equilibrium at a constant temperature of 350 ℃, measuring infrared signals, subtracting background signals, and calculating to obtain the final acid amount (reference of "Preparation of the surface Ti, Al rich ETS-10 and modification of position structure and acidity by purification and regeneration", microprous and microprous Materials, Volume 145, Pages 224-.
Catalyst preparation and isomerization reaction testing
The catalyst is prepared according to the method disclosed in US8790507B2, and the composition ratio of the catalyst is as follows: alumina: pt: 65:35: 0.35.
The isomerization test of the catalyst is carried out on a micro-reaction device, n-hexadecane is taken as a model compound, the reaction conditions are normal pressure, the hydrogen-oil ratio is 500:1, and the mass space velocity is 2.3h -1 The overall conversion was adjusted to 94% with the change in temperature and the isohexadecane selectivity data was tested at 94% overall conversion, with the results shown in table 2.
TABLE 2
The results in table 2 show that the examples of the present invention have significantly better effects, and the samples obtained by the examples of the present invention have lower reaction temperature under the same conversion rate, which indicates higher catalyst activity, wherein the reaction temperatures of a1, a2, a7 and A8 are not more than 290 ℃, and the isomerization selectivity is higher, not less than 95%.
The preferred embodiments of the present invention have been described above in detail, but the present invention is not limited thereto. Within the scope of the technical idea of the invention, many simple modifications can be made to the technical solution of the invention, including combinations of various technical features in any other suitable way, and these simple modifications and combinations should also be regarded as the disclosure of the invention, and all fall within the scope of the invention.
Claims (14)
1. A method for preparing a molecular sieve rich in aluminum on the surface, which comprises the following steps:
(1) preparing a precursor gel A, B, wherein the silicon-aluminum ratio of the precursor gel A is 40-100, the silicon-aluminum ratio of the precursor gel B is 100-400, and the silicon-aluminum ratios of the precursor gel A and the precursor gel B are different;
(2) respectively carrying out first-step crystallization on the precursor gels A, B;
(3) respectively preparing a first-step crystallization product from the precursor gel A, B according to a mass ratio of 1: (3-50) mixing, and performing second-step crystallization to finally prepare the molecular sieve with the aluminum-rich surface;
in the step (2), the first crystallization condition of the precursor gel A comprises: the temperature is 150 ℃ and 190 ℃, and the time is 3-120 h;
in the step (2), the first crystallization condition of the precursor gel B comprises: the temperature is 150 ℃ and 190 ℃, and the time is 3-120 h;
the conditions of the second step crystallization include: the temperature is 150-190 ℃, and the time is 6-48 h;
the molecular sieve is a ZSM-48 molecular sieve, the silicon-aluminum ratio of the particle surface of the molecular sieve within 50nm of the thickness is 40-150, and the silicon-aluminum ratio of the whole molecular sieve is 150-300.
2. The method of claim 1, wherein in step (1), the precursor gel A, B is prepared from a template, a silicon source, an aluminum source, water, and sodium hydroxide.
3. The method of claim 2, wherein the molar ratio of the silicon source, the aluminum source, the water, the base, and the templating agent in the precursor gel a is 1: (0.01-0.025): (10-40): (0.11-0.19): (0.0175-0.0215);
in the precursor gel B, the molar ratio of the silicon source, the aluminum source, the water, the alkali and the template agent is 1: (0.0025-0.01): (10-40): (0.11-0.19): (0.0175-0.0215);
wherein the silicon source is SiO 2 The aluminum source is calculated as Al 2 O 3 Based on the base
And (6) counting.
4. The process of claim 2 or 3, wherein the silicon source is silica sol and the aluminum source is sodium metaaluminate.
5. The method of claim 1, wherein in step (2), the conditions for the first step crystallization of precursor gel a comprise: the temperature is 150 ℃ and 160 ℃; the time is 4-24 h.
6. The method of claim 1 or 5, wherein in step (2), the conditions for the first crystallization of precursor gel A comprise: the time is 8-16 h.
7. The method of claim 1, wherein in step (2), the first crystallization conditions of the precursor gel B comprise: the temperature is 150-160 ℃; the time is 12-48 h.
8. The method of claim 1 or 7, wherein in step (2), the first crystallization conditions of the precursor gel B comprise: the time is 16-32 h.
9. The method of claim 1, wherein the conditions of the second crystallization step include: the time is 8-12 h.
10. A surface aluminum-enriched molecular sieve prepared by the process of any of claims 1-9.
11. The molecular sieve of claim 10, wherein the molecular sieve has a silica to alumina ratio within 50nm of the thickness of the particle surface of 40 to 90.
12. Use of the molecular sieve of claim 10 or 11 in an isomerization of a paraffin.
13. An isomerization catalyst comprising a binder, a metal active component and the molecular sieve of claim 10 or 11.
14. Use of the isomerization catalyst of claim 13 in an isomerization of alkanes.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5254327A (en) * | 1992-04-03 | 1993-10-19 | Intevep, S.A. | Zeolitic catalyst of MFI type, its preparation and use |
| CN1363517A (en) * | 2000-12-19 | 2002-08-14 | 普莱克斯技术有限公司 | Synthesis of aluminium riched AFI zeolite |
| CN101096274A (en) * | 2006-06-29 | 2008-01-02 | 中国石油化工股份有限公司 | Preparation method of aluminum-enriched beta zeolite |
| CN101274764A (en) * | 2007-03-30 | 2008-10-01 | 中国石油化工股份有限公司 | Preparation for nanometer allitic beta-zeolite |
| CN102616807A (en) * | 2012-03-29 | 2012-08-01 | 北京化工大学 | Method for synthesizing Y type molecular sieve |
| CN103803576A (en) * | 2012-11-07 | 2014-05-21 | 中国石油化工股份有限公司 | ZSM-48 molecular sieve with low silica-alumina ratio and preparation method thereof |
| CN105967202A (en) * | 2016-05-03 | 2016-09-28 | 太原理工大学 | Synthetic method of ZSM-48 molecular sieve with low silica-alumina ratio |
-
2018
- 2018-08-24 CN CN201810974981.8A patent/CN110856819B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5254327A (en) * | 1992-04-03 | 1993-10-19 | Intevep, S.A. | Zeolitic catalyst of MFI type, its preparation and use |
| CN1363517A (en) * | 2000-12-19 | 2002-08-14 | 普莱克斯技术有限公司 | Synthesis of aluminium riched AFI zeolite |
| CN101096274A (en) * | 2006-06-29 | 2008-01-02 | 中国石油化工股份有限公司 | Preparation method of aluminum-enriched beta zeolite |
| CN101274764A (en) * | 2007-03-30 | 2008-10-01 | 中国石油化工股份有限公司 | Preparation for nanometer allitic beta-zeolite |
| CN102616807A (en) * | 2012-03-29 | 2012-08-01 | 北京化工大学 | Method for synthesizing Y type molecular sieve |
| CN103803576A (en) * | 2012-11-07 | 2014-05-21 | 中国石油化工股份有限公司 | ZSM-48 molecular sieve with low silica-alumina ratio and preparation method thereof |
| CN105967202A (en) * | 2016-05-03 | 2016-09-28 | 太原理工大学 | Synthetic method of ZSM-48 molecular sieve with low silica-alumina ratio |
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