CN110961149A - Modified SAPO-11 molecular sieve, and preparation method and application thereof - Google Patents
Modified SAPO-11 molecular sieve, and preparation method and application thereof Download PDFInfo
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- 239000002808 molecular sieve Substances 0.000 title claims abstract description 219
- 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 219
- 238000002360 preparation method Methods 0.000 title claims abstract description 10
- 239000003054 catalyst Substances 0.000 claims abstract description 44
- 238000011282 treatment Methods 0.000 claims abstract description 40
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims abstract description 39
- 238000002715 modification method Methods 0.000 claims abstract description 38
- 239000003513 alkali Substances 0.000 claims abstract description 33
- QGZKDVFQNNGYKY-UHFFFAOYSA-O ammonium group Chemical group [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 claims abstract description 32
- 238000001035 drying Methods 0.000 claims abstract description 21
- 238000005406 washing Methods 0.000 claims abstract description 17
- 230000007935 neutral effect Effects 0.000 claims abstract description 11
- ZMANZCXQSJIPKH-UHFFFAOYSA-N Triethylamine Chemical compound CCN(CC)CC ZMANZCXQSJIPKH-UHFFFAOYSA-N 0.000 claims abstract description 9
- HZAXFHJVJLSVMW-UHFFFAOYSA-N 2-Aminoethan-1-ol Chemical compound NCCO HZAXFHJVJLSVMW-UHFFFAOYSA-N 0.000 claims abstract description 6
- QUSNBJAOOMFDIB-UHFFFAOYSA-N Ethylamine Chemical compound CCN QUSNBJAOOMFDIB-UHFFFAOYSA-N 0.000 claims abstract description 6
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 claims abstract description 3
- GSEJCLTVZPLZKY-UHFFFAOYSA-N Triethanolamine Chemical compound OCCN(CCO)CCO GSEJCLTVZPLZKY-UHFFFAOYSA-N 0.000 claims abstract description 3
- 235000011114 ammonium hydroxide Nutrition 0.000 claims abstract description 3
- ZBCBWPMODOFKDW-UHFFFAOYSA-N diethanolamine Chemical compound OCCNCCO ZBCBWPMODOFKDW-UHFFFAOYSA-N 0.000 claims abstract description 3
- HPNMFZURTQLUMO-UHFFFAOYSA-N diethylamine Chemical compound CCNCC HPNMFZURTQLUMO-UHFFFAOYSA-N 0.000 claims abstract description 3
- 238000006317 isomerization reaction Methods 0.000 claims description 43
- DCAYPVUWAIABOU-UHFFFAOYSA-N hexadecane Chemical group CCCCCCCCCCCCCCCC DCAYPVUWAIABOU-UHFFFAOYSA-N 0.000 claims description 39
- 238000004517 catalytic hydrocracking Methods 0.000 claims description 35
- 150000001335 aliphatic alkanes Chemical class 0.000 claims description 23
- NLXLAEXVIDQMFP-UHFFFAOYSA-N Ammonia chloride Chemical compound [NH4+].[Cl-] NLXLAEXVIDQMFP-UHFFFAOYSA-N 0.000 claims description 8
- 230000004048 modification Effects 0.000 claims description 7
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- PAWQVTBBRAZDMG-UHFFFAOYSA-N 2-(3-bromo-2-fluorophenyl)acetic acid Chemical compound OC(=O)CC1=CC=CC(Br)=C1F PAWQVTBBRAZDMG-UHFFFAOYSA-N 0.000 claims description 2
- ATRRKUHOCOJYRX-UHFFFAOYSA-N Ammonium bicarbonate Chemical compound [NH4+].OC([O-])=O ATRRKUHOCOJYRX-UHFFFAOYSA-N 0.000 claims description 2
- 239000001099 ammonium carbonate Substances 0.000 claims description 2
- 235000012501 ammonium carbonate Nutrition 0.000 claims description 2
- BFNBIHQBYMNNAN-UHFFFAOYSA-N ammonium sulfate Chemical compound N.N.OS(O)(=O)=O BFNBIHQBYMNNAN-UHFFFAOYSA-N 0.000 claims description 2
- 229910052921 ammonium sulfate Inorganic materials 0.000 claims description 2
- 235000011130 ammonium sulphate Nutrition 0.000 claims description 2
- 229910052710 silicon Inorganic materials 0.000 abstract description 27
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 abstract description 20
- 239000010703 silicon Substances 0.000 abstract description 20
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- 238000005336 cracking Methods 0.000 abstract description 14
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- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 229910021536 Zeolite Inorganic materials 0.000 description 1
- 238000010306 acid treatment Methods 0.000 description 1
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- HNPSIPDUKPIQMN-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Al]O[Al]=O HNPSIPDUKPIQMN-UHFFFAOYSA-N 0.000 description 1
- 230000002708 enhancing effect Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- ZZUFCTLCJUWOSV-UHFFFAOYSA-N furosemide Chemical compound C1=C(Cl)C(S(=O)(=O)N)=CC(C(O)=O)=C1NCC1=CC=CO1 ZZUFCTLCJUWOSV-UHFFFAOYSA-N 0.000 description 1
- 238000005470 impregnation Methods 0.000 description 1
- 229910001387 inorganic aluminate Inorganic materials 0.000 description 1
- 229910052909 inorganic silicate Inorganic materials 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
- B01J29/82—Phosphates
- B01J29/84—Aluminophosphates containing other elements, e.g. metals, boron
- B01J29/85—Silicoaluminophosphates [SAPO compounds]
-
- 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
- B01J35/63—Pore volume
- B01J35/633—Pore volume less than 0.5 ml/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
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/02—Impregnation, coating or precipitation
- B01J37/0201—Impregnation
- B01J37/0207—Pretreatment of the support
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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
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/30—Ion-exchange
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
- C10G47/00—Cracking of hydrocarbon oils, in the presence of hydrogen or hydrogen- generating compounds, to obtain lower boiling fractions
- C10G47/02—Cracking of hydrocarbon oils, in the presence of hydrogen or hydrogen- generating compounds, to obtain lower boiling fractions characterised by the catalyst used
- C10G47/10—Cracking of hydrocarbon oils, in the presence of hydrogen or hydrogen- generating compounds, to obtain lower boiling fractions characterised by the catalyst used with catalysts deposited on a carrier
- C10G47/12—Inorganic carriers
- C10G47/14—Inorganic carriers the catalyst containing platinum group metals or compounds thereof
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- 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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- B—PERFORMING OPERATIONS; TRANSPORTING
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- 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
- B01J2229/30—After treatment, characterised by the means used
- B01J2229/38—Base treatment
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Abstract
The invention provides a modified SAPO-11 molecular sieve, and a preparation method and application thereof. The modification method of the SAPO-11 molecular sieve comprises the following steps: the SAPO-11 molecular sieve is put into 0.05 to 1mol/L alkali solution for treatment for 0.3 to 2 hours at the temperature of between 30 and 90 ℃; wherein the alkali comprises at least one of sodium hydroxide, ammonia water, ethylamine, diethylamine, triethylamine, ethanolamine, diethanolamine and triethanolamine; washing the SAPO-11 molecular sieve subjected to alkali treatment to be neutral, and performing ammonium exchange treatment; and after ammonium exchange treatment, washing, drying and roasting. The modification method can introduce mesopores and reduce the loss of silicon islands as much as possible, the mesopore volume of the prepared modified SAPO-11 molecular sieve is increased while the relative content of aluminum is kept unchanged basically, and the end position cracking activity of the catalyst taking the modified SAPO-11 molecular sieve as a carrier is improved.
Description
Technical Field
The invention belongs to the field of molecular sieves, and relates to a modified SAPO-11 molecular sieve, and a preparation method and application thereof.
Background
With the development of human society, the consumption of fossil energy has sharply increased. This not only causes an energy crisis but also brings about serious environmental problems. Therefore, the search for an alternative new energy is urgent. The aviation industry in China belongs to an important part of transportation, and consumes a large amount of petrochemical aviation fuel every year. It is therefore of great practical interest to find an alternative aviation fuel. At present, only biomass aviation fuel has great application prospect. The biomass aviation fuel is produced by using animal and vegetable oil as a raw material and adopting a hydrogenation technology, a catalyst system and a process technology. Biological oil can be derived to obtain C15-C20And aviation fuel requires C9-C15The isomeric hydrocarbon to meet the requirement of high-altitude flight on low-temperature fluidity of oil products. Therefore, the preparation of the bio-aviation fuel requires a hydrocracking/isomerization process, and the catalyst is the core of the process, and a high-selectivity end-position hydrocracking/isomerization catalyst is needed, which cannot cause deep cracking. The Huangwei nations and the like evaluate the catalytic performances of Pt/SAPO-11, Pt/Beta, Pt/ZSM-5 and Pt/MCM-22, and find that the Pt/SAPO-11 has higher isomerization selectivity (the Huangwei nations, the great east of Li, Shiyahua and the like, the hydroisomerization reaction of n-hexadecane on a molecular sieve catalyst [ J]Catalytic bulletin 2003,24(9): 651-657). Wang et al examined the isomerization performance of Pt/SAPO-11 and Pt/ZSM-22 using soybean oil as raw material, and found that the isomerization performance of Pt/SAPO-11 was excellent (Wang C, Tiann Z, Wang L, et al, one-step hydro of flexible oil to product high quality diesel-random Kanes [ J]Chemsuschem,2012,5(10): 1974-83). Current research indicates that SAPO-11 molecular sieve mainly has good isomerization performance, but short plates with insufficient cracking capacity exist in the preparation process of biological aviation fuel, and published literature reports are mostly focused on research for improving the isomerization performanceHowever, the research on moderately increasing the cracking performance is less, so that the research on a novel modification method of the SAPO-11 molecular sieve is of great significance.
The SAPO-11 molecular sieve is an AEL topological structure, and the framework of the AEL topological structure is made of SiO4、AlO4And PO4The tetrahedron is formed, the structure has a straight pore channel structure with one-dimensional ten-membered ring ellipse, the pore channel size is 0.39 multiplied by 0.63nm, compared with Y molecular sieve, β molecular sieve and ZSM-5 molecular sieve, SAPO-11 molecular sieve has weaker acidity and cannot cause deep cracking, but short plates with insufficient cracking capability still exist in the preparation process of the biological aviation fuel, so the cracking capability needs to be properly enhanced.
The relevant scholars have done a great deal of work on the synthesis of SAPO-11 molecular sieves. However, the SAPO-11 molecular sieve synthesized in one time has more micropores and is weaker in acidity. The raw material for preparing the biological aviation fuel is long-chain normal alkane, and the existence of micropores reduces the number of accessible active sites, so that the conversion rate of reactants and the yield of target products are reduced. We therefore try to introduce a suitable amount of mesopores to increase the number of accessible active sites or to enhance the acidity of the molecular sieve in a suitable amount, with the ultimate aim of enhancing the yield of end-position cracked products.
Generally, SAPO-11 molecular sieve is substituted with Si for APO 411 is phosphorus or aluminum in molecular sieves. There are three possible ways of entering Si into the framework: (1) si substituted APO4-11 framework Al in molecular sieve, i.e. SM I mechanism; (2) si substituted APO411 framework P in molecular sieve, i.e. SM II mechanism; (3) si substituted APO4Framework Al and framework P in 11 molecular sieves, i.e., the SM III mechanism. Studies have shown that the framework structure is positively charged in SM I mechanisms, which is not present. In the SM II mechanism, the backbone structure is negatively charged and can generate protonic acid centers. In the SM III mechanism, the skeleton structure is electrically neutral. Wherein, the SMII mechanism can generate an Si (4Al) structure to form a weak acid acidic site; the SM III mechanism readily generates Si-aggregated silicon islands, where Si at the boundaries of the silicon islands and the surrounding environment can form Si (1-3Al) structures that can produce strong acid sites. The formation of silicon islands can improve the acid strength of the SAPO molecular sieve and the acid at the boundaries of the silicon islandsThe center is strongest and increases with increasing silicon island size (chenchenchensie, shin-front, prince, etc.. a Si (4Al) -rich SAPO-44 molecular sieve with multi-stage pore sizes and its molecular sieve catalyst and methods of making the same).
There are many methods for introducing mesopores into an SAPO-11 molecular sieve reported in literature, and the mesopores are mostly introduced by removing framework elements of the molecular sieve, and the change of the framework elements of the molecular sieve can influence the acidity of the molecular sieve. Liuqiang and the like research the influence of acid and salt treatment on the physical and chemical properties and catalytic performance of the Pt/SAPO-11. The experimental result shows that the acid salt treatment can not only remove the aluminum of the molecular sieve, but also remove the phosphorus and the silicon of the molecular sieve (Liuqiang, Dujunchen, Zhang Aimin, and the like. the influence of the acid and salt treatment on the physical and chemical properties and the catalytic properties of Pt/SAPO-11 [ J ] the report of fuel chemistry, 2017(3): 337-344.).
The weak acid structure of Si (4Al) and the strong acid structure of Si (1-3Al) exist in the SAPO-11 molecular sieve. Wherein the Si (1-3Al) structure belongs to the silicon island boundary environment, and strong acid sites can be generated between the silicon at the silicon island boundary of the SAPO-11 molecular sieve and the surrounding environment. In order to reduce the loss of strong acid sites, the removal of silicon and aluminum is reduced when the mesopores are introduced. An ideal method for introducing mesopores is to retain silicon and aluminum to the maximum extent on the premise of removing phosphorus. This reduces the loss of silicon islands.
However, in the current research on molecular sieves, in order to solve the problem that the molecular sieves are limited in contact with active sites due to the existence of micropores, acid-base modification is often used to introduce mesopores, and both acid treatment and alkali treatment are used to introduce a proper amount of mesopores by removing a part of framework species (including Si and Al) of the molecular sieves. For example, alkali treatment is adopted to treat the SAPO-34 molecular sieve, and mesopores are introduced through the removal of Si and Al, but because of the great removal of Si and Al, the contents of Si and Al of the modified molecular sieve are both obviously reduced, and the reduction of the framework species, particularly the content of Al, of the removed molecular sieve greatly influences the acidity of the molecular sieve.
The problem of the SAPO-11 molecular sieve modification field is to find a SAPO-11 molecular sieve modification method which can introduce mesopores and can not reduce the relative contents of Si and Al.
Disclosure of Invention
In view of the fact that the SAPO-11 molecular sieve synthesized at one time at present has excellent isomerization capability and short plates with insufficient cracking capability, the existing SAPO-11 molecular sieve modification method has the problem that a large amount of desilication and dealumination damage silicon islands. The invention aims to provide a modification method of an SAPO-11 molecular sieve, which can introduce mesopores and reduce the loss of silicon islands as much as possible, wherein the modification method can introduce the mesopores into the SAPO-11 molecular sieve, simultaneously can keep the relative content of aluminum basically unchanged, and reduce the damage to the silicon islands. The modified SAPO-11 molecular sieve prepared by the method is used as a carrier of a long-chain alkane hydrocracking/isomerization catalyst, shows good end-position cracking activity, and has excellent cracking performance and isomerization performance.
In order to achieve the aim, the invention provides a modification method of an SAPO-11 molecular sieve, which comprises the following steps:
1) at the temperature of 30-90 ℃, the SAPO-11 molecular sieve is put into an alkali solution with the concentration of 0.05-1mol/L for alkali treatment for 0.3-2h (for example, 0.5 h); wherein the alkali comprises at least one of sodium hydroxide, ammonia water, ethylamine, diethylamine, triethylamine, ethanolamine, diethanolamine and triethanolamine;
2) after the SAPO-11 molecular sieve subjected to alkali treatment is washed to be neutral, ammonium exchange treatment is carried out;
3) and (3) washing and drying the ammonium-exchanged SAPO-11 molecular sieve, and roasting to realize modification of the SAPO-11 molecular sieve.
In the above molecular sieve modification method, preferably, the concentration of the alkali solution is 0.1 to 0.5 mol/L.
In the above molecular sieve modification method, preferably, the base is sodium hydroxide.
In the above molecular sieve modification method, it is preferable that the mass ratio of the SAPO-11 molecular sieve to the alkali solution is 1:40 to 1:5, for example, 1: 20.
In the above molecular sieve modification method, preferably, the temperature of the alkali treatment is 35 to 85 ℃.
In the above molecular sieve modification method, preferably, the ammonium exchange medium used in the ammonium exchange treatment includes at least one of ammonium chloride, ammonium sulfate, ammonium nitrate, and ammonium carbonate, more preferably ammonium chloride.
In the above molecular sieve modification method, the number of times of the ammonium exchange treatment is preferably not less than two, more preferably two. In one embodiment, the ammonium exchange process comprises: and (2) putting the SAPO-11 molecular sieve into a solution containing an ammonium exchange medium for carrying out first ammonium exchange treatment, washing the SAPO-11 molecular sieve subjected to the first ammonium exchange treatment to be neutral, drying, and then putting the dried SAPO-11 molecular sieve into the solution containing the ammonium exchange medium for carrying out second ammonium exchange treatment.
In the above molecular sieve modification method, preferably, the calcination temperature is set at 350-650 ℃, more preferably 400-600 ℃.
In the above molecular sieve modification method, preferably, the calcination time is 3 to 8 hours.
In the molecular sieve modification method, before ammonium exchange treatment, the SAPO-11 molecular sieve which is washed to be neutral is preferably dried; among them, the drying may be carried out at 80 to 160 ℃ and preferably at 85 to 150 ℃.
In the above molecular sieve modification method, the drying in step 3) may be carried out at 80 to 160 ℃, preferably at 85 to 150 ℃.
The invention also provides a modified SAPO-11 molecular sieve prepared by the SAPO-11 molecular sieve modification method.
In the above-described modified SAPO-11 molecular sieve, preferably, the modified SAPO-11 molecular sieve has a crystallinity of not less than 70%.
The invention also provides an application of the modified SAPO-11 molecular sieve in preparation of a long paraffin hydrocarbon hydrocracking/isomerization catalyst, in particular an application of the modified SAPO-11 molecular sieve as a carrier of the long paraffin hydrocarbon hydrocracking/isomerization catalyst in preparation of the long paraffin hydrocarbon hydrocracking/isomerization catalyst.
In the above application, preferably, the long-chain alkane hydrocracking/isomerization catalyst is long-chain alkane hydrocracking/isomerization to C9-C15Catalyst for isoparaffin。
In the above application, preferably, the long-chain alkane is n-hexadecane.
The invention also provides a long-chain alkane hydrocracking/isomerization catalyst, wherein the catalyst takes the modified SAPO-11 molecular sieve as a carrier.
In the above-mentioned long paraffin hydrocracking/isomerization catalyst, preferably, the active component of the catalyst is Pt; more preferably, the catalyst employs impregnation of a precursor of Pt (e.g., H)2PtCl6) Dipping the modified SAPO-11 molecular sieve and roasting to obtain the modified SAPO-11 molecular sieve. Wherein the mass of the Pt accounts for 0.5 percent of the mass of the molecular sieve.
In one embodiment, the long-chain alkane hydrocracking/isomerization catalyst is prepared by the following method: 1) h is to be2PtCl6·6H2Dropwise adding an O aqueous solution into the ground modified SAPO-11 molecular sieve to realize H2PtCl6Dipping the modified SAPO-11 molecular sieve to finish dipping treatment, wherein the mass of Pt accounts for 0.5 percent of the mass of the molecular sieve; 2) and roasting the SAPO-11 molecular sieve subjected to the dipping treatment to obtain the long-chain alkane hydrocracking/isomerization catalyst.
The weak acid structure of Si (4Al) and the strong acid structure of Si (1-3Al) exist in the SAPO-11 molecular sieve. Wherein the Si (1-3Al) structure belongs to the silicon island boundary environment, which provides strong acid sites. When mesopores are introduced into the molecular sieve, the removal of Si and Al is required to be reduced in order not to reduce the loss of strong acid sites. Since P can only exist in an Al-P-Al structure, one ideal method for introducing mesopores is to remove P without damaging Si and Al.
The modification method of the SAPO-11 molecular sieve provided by the invention mainly introduces mesopores by taking phosphorus removal species as a main component in the SAPO-11 molecular sieve, and the relative content of aluminum can be kept basically unchanged in the introduction process of the mesopores, so that the damage to silicon islands in the modification process is greatly reduced, and the damage to strong acid sites is reduced to a certain extent.
Compared with the prior art, the method has the following advantages:
1) the modification method of the SAPO-11 molecular sieve provided by the invention realizes the great improvement of the external specific surface area, the total pore volume and the mesoporous volume of the molecular sieve; in a specific embodiment, compared with the unmodified SAPO-11 molecular sieve, the external specific surface area of the modified SAPO-11 molecular sieve is increased by 15.58%, the total pore volume is increased by 49.18%, and the mesoporous volume is increased by 67.07%.
2) The modification method of the SAPO-11 molecular sieve provided by the invention gives consideration to the double improvement of the acid strength and the mesoporous volume of the SAPO-11 molecular sieve.
3) The long-chain alkane hydrocracking/isomerization catalyst prepared by using the modified SAPO-11 molecular sieve as a carrier shows good end-position cracking activity when used for catalyzing the long-chain alkane hydrocracking/isomerization reaction, and has good cracking performance and isomerization performance; in particular to a method for preparing C by catalyzing hydrocracking/isomerization reaction of hexadecane9-C15When isoalkanes are used, C in the product9-C15The content of hydrocarbon is obviously increased, and C is simultaneously9-C15The mass ratio of the isomerized hydrocarbons to the normal hydrocarbons in the hydrocarbon is also increased.
Drawings
FIG. 1 is an XRD spectrum of an unmodified SAPO-11 molecular sieve.
FIG. 2 is an XRD spectrum of the modified SAPO-11 molecular sieve provided in example 1.
FIG. 3 is an XRD spectrum of the modified SAPO-11 molecular sieve provided in example 2.
FIG. 4 is an XRD spectrum of the modified SAPO-11 molecular sieve provided in example 3.
FIG. 5 is an XRD spectrum of the modified SAPO-11 molecular sieve provided in example 4.
FIG. 6 is NH of unmodified SAPO-11 molecular sieve3TPD spectrum and NH of modified SAPO-11 molecular sieves as provided in examples 1 to 43-TPD spectrum.
Detailed Description
The technical solutions of the present invention will be described in detail below in order to clearly understand the technical features, objects, and advantages of the present invention, but the present invention is not limited to the practical scope of the present invention.
Comparative example 1
The present comparative example provides a long chain alkane hydrocracking/isomerization catalyst prepared by the following method:
(1) taking commercially available SAPO-11 molecular sieve raw powder (the X-ray diffraction characterization of the SAPO-11 molecular sieve raw powder is shown in figure 1, and as can be seen from figure 1, the molecular sieve has an AEL topological structure and is an SAPO-11 molecular sieve), carrying out a water absorption test, and measuring the water absorption value to be 136.5%;
(2) weighing 10g of SAPO-11 molecular sieve raw powder, accurately weighing 13.65g of deionized water according to the measured water absorption, and accurately weighing 0.135g of H according to the mass fraction of Pt in the molecular sieve of 0.5 percent2PtCl6·6H2O; h is to be2PtCl6·6H2Dissolving O in 13.65g of deionized water to obtain a chloroplatinic acid solution, dropwise adding the chloroplatinic acid solution on a molecular sieve, drying overnight at room temperature, and drying in an oven at 120 ℃ for 12 hours to obtain a product A;
(3) and roasting the product A in a muffle furnace at 550 ℃ for 4h to obtain the long-chain alkane hydrocracking/isomerization catalyst, which is named as Pt/SAPO-11.
Example 1
The embodiment provides a modified SAPO-11 molecular sieve, and the modification method of the SAPO-11 molecular sieve comprises the following steps:
(1) taking 10g of commercial SAPO-11 molecular sieve raw powder which is the same as the commercial SAPO-11 molecular sieve raw powder in the comparative example 1, uniformly mixing the commercial SAPO-11 molecular sieve raw powder with 200g of sodium hydroxide solution with the concentration of 0.05mol/L (the mass ratio of the SAPO-11 molecular sieve to the sodium hydroxide solution is 1:20), and stirring the mixture for 0.5h at the temperature of 40 ℃ for alkali treatment;
(2) carrying out suction filtration and water washing on the molecular sieve subjected to alkali treatment until the molecular sieve is neutral, and then drying the molecular sieve in an oven at 120 ℃ overnight;
(3) accurately preparing NH with the concentration of 0.50mol/L4Cl solution, molecular sieve after alkali treatment and NH4Uniformly mixing Cl solution according to the solid-liquid mass ratio of 1:20, and then carrying out primary ammonium exchange for 1h at 80 ℃; washing the molecular sieve after the first ammonium exchange with water, filtering to neutrality, and drying in an oven at 120 ℃ overnight;
(4) will be described in detail(3) Dried molecular sieve and 0.50mol/L NH4Uniformly mixing Cl solution according to the solid-liquid mass ratio of 1:20, and then carrying out secondary ammonium exchange for 1h at 80 ℃; washing the molecular sieve subjected to the second ammonium exchange with water, performing suction filtration to neutrality, and then drying in an oven at 120 ℃ overnight;
(5) and (3) roasting the molecular sieve dried in the step (4) at 550 ℃ for 4h to obtain a modified SAPO-11 molecular sieve, and naming the molecular sieve as 0.05M-SAPO-11.
The modified SAPO-11 molecular sieve 0.05M-SAPO-11 provided in the example was subjected to X-ray diffraction characterization, and the results are shown in FIG. 2. As can be seen from FIG. 2, the modified SAPO-11 molecular sieve 0.05M-SAPO-11 still has an AEL topology.
This example provides a long-chain alkane hydrocracking/isomerization catalyst, which is prepared by the following method:
(6) taking the modified SAPO-11 molecular sieve 0.05M-SAPO-11 provided by the embodiment to perform a water absorption test, and measuring that the water absorption value is 136.5%;
(7) weighing 10g of the modified SAPO-11 molecular sieve 0.05M-SAPO-11 provided by the embodiment, accurately weighing 13.65g of deionized water according to the measured water absorption, and accurately weighing 0.135g of H according to the mass fraction of Pt in the molecular sieve of 0.5 percent2PtCl6·6H2O; h is to be2PtCl6·6H2Dissolving O in 13.65g of deionized water to obtain a chloroplatinic acid solution, dropwise adding the chloroplatinic acid solution on a molecular sieve, drying overnight at room temperature, and drying in an oven at 120 ℃ for 12 hours to obtain a product A;
(8) and roasting the product A in a muffle furnace at 550 ℃ for 4h to obtain the long-chain alkane hydrocracking/isomerization catalyst, which is named as Pt/0.05M-SAPO-11.
Example 2
The embodiment provides a modified SAPO-11 molecular sieve, and the modification method of the SAPO-11 molecular sieve comprises the following steps:
(1) taking 10g of commercial SAPO-11 molecular sieve raw powder which is the same as the commercial SAPO-11 molecular sieve raw powder in the comparative example 1, uniformly mixing the commercial SAPO-11 molecular sieve raw powder with 200g of sodium hydroxide solution with the concentration of 0.10mol/L (the mass ratio of the SAPO-11 molecular sieve to the sodium hydroxide solution is 1:20), and stirring the mixture for 0.5h at the temperature of 40 ℃ for alkali treatment;
(2) carrying out suction filtration and water washing on the molecular sieve subjected to alkali treatment until the molecular sieve is neutral, and then drying the molecular sieve in an oven at 120 ℃ overnight;
(3) accurately preparing NH with the concentration of 0.50mol/L4Cl solution, molecular sieve after alkali treatment and NH4Uniformly mixing Cl solution according to the solid-liquid mass ratio of 1:20, and then carrying out primary ammonium exchange for 1h at 80 ℃; washing the molecular sieve after the first ammonium exchange with water, filtering to neutrality, and drying in an oven at 120 ℃ overnight;
(4) mixing the molecular sieve dried in the step (3) with 0.50mol/L NH4Uniformly mixing Cl solution according to the solid-liquid mass ratio of 1:20, and then carrying out secondary ammonium exchange for 1h at 80 ℃; washing the molecular sieve subjected to the second ammonium exchange with water, performing suction filtration to neutrality, and then drying in an oven at 120 ℃ overnight;
(5) and (3) roasting the molecular sieve dried in the step (4) at 550 ℃ for 4h to obtain a modified SAPO-11 molecular sieve, and naming the molecular sieve as 0.10M-SAPO-11.
The modified SAPO-11 molecular sieve 0.10M-SAPO-11 provided in the example was subjected to X-ray diffraction characterization, and the results are shown in FIG. 3. As can be seen in FIG. 3, the modified SAPO-11 molecular sieve 0.10M-SAPO-11 still has an AEL topology.
Example 3
The embodiment provides a modified SAPO-11 molecular sieve, and the modification method of the SAPO-11 molecular sieve comprises the following steps:
(1) taking 10g of commercial SAPO-11 molecular sieve raw powder which is the same as the commercial SAPO-11 molecular sieve raw powder in the comparative example 1, uniformly mixing the commercial SAPO-11 molecular sieve raw powder with 200g of sodium hydroxide solution with the concentration of 0.30mol/L (the mass ratio of the SAPO-11 molecular sieve to the sodium hydroxide solution is 1:20), and stirring the mixture for 0.5h at the temperature of 40 ℃ for alkali treatment;
(2) carrying out suction filtration and water washing on the molecular sieve subjected to alkali treatment until the molecular sieve is neutral, and then drying the molecular sieve in an oven at 120 ℃ overnight;
(3) accurately preparing NH with the concentration of 0.50mol/L4Cl solution, molecular sieve after alkali treatment and NH4Uniformly mixing Cl solution according to the solid-liquid mass ratio of 1:20, and then carrying out primary ammonium exchange for 1h at 80 ℃; washing and filtering the molecular sieve after the first ammonium exchangeTo neutral and then dried in an oven at 120 ℃ overnight;
(4) mixing the molecular sieve dried in the step (3) with 0.50mol/L NH4Uniformly mixing Cl solution according to the solid-liquid mass ratio of 1:20, and then carrying out secondary ammonium exchange for 1h at 80 ℃; washing the molecular sieve subjected to the second ammonium exchange with water, performing suction filtration to neutrality, and then drying in an oven at 120 ℃ overnight;
(5) and (3) roasting the molecular sieve dried in the step (4) at 550 ℃ for 4h to obtain a modified SAPO-11 molecular sieve, and naming the molecular sieve as 0.30M-SAPO-11.
The modified SAPO-11 molecular sieve 0.30M-SAPO-11 provided in the example was subjected to X-ray diffraction characterization, and the results are shown in FIG. 4. As can be seen in FIG. 4, the modified SAPO-11 molecular sieve 0.30M-SAPO-11 still has an AEL topology.
Example 4
The embodiment provides a modified SAPO-11 molecular sieve, and the modification method of the SAPO-11 molecular sieve comprises the following steps:
(1) taking 10g of commercial SAPO-11 molecular sieve raw powder which is the same as the commercial SAPO-11 molecular sieve raw powder in the comparative example 1, uniformly mixing the commercial SAPO-11 molecular sieve raw powder with 200g of sodium hydroxide solution with the concentration of 0.50mol/L (the mass ratio of the SAPO-11 molecular sieve to the sodium hydroxide solution is 1:20), and stirring the mixture for 0.5h at the temperature of 40 ℃ for alkali treatment;
(2) carrying out suction filtration and water washing on the molecular sieve subjected to alkali treatment until the molecular sieve is neutral, and then drying the molecular sieve in an oven at 120 ℃ overnight;
(3) accurately preparing NH with the concentration of 0.50mol/L4Cl solution, molecular sieve after alkali treatment and NH4Uniformly mixing Cl solution according to the solid-liquid mass ratio of 1:20, and then carrying out primary ammonium exchange for 1h at 80 ℃; washing the molecular sieve after the first ammonium exchange with water, filtering to neutrality, and drying in an oven at 120 ℃ overnight;
(4) mixing the molecular sieve dried in the step (3) with 0.50mol/L NH4Uniformly mixing Cl solution according to the solid-liquid mass ratio of 1:20, and then carrying out secondary ammonium exchange for 1h at 80 ℃; washing the molecular sieve subjected to the second ammonium exchange with water, performing suction filtration to neutrality, and then drying in an oven at 120 ℃ overnight;
(5) and (3) roasting the molecular sieve dried in the step (4) at 550 ℃ for 4h to obtain a modified SAPO-11 molecular sieve, and naming the molecular sieve as 0.50M-SAPO-11.
The modified SAPO-11 molecular sieve 0.50M-SAPO-11 provided in this example was subjected to X-ray diffraction characterization, and the results are shown in FIG. 5. As can be seen in FIG. 5, the modified SAPO-11 molecular sieve 0.50M-SAPO-11 still has an AEL topology.
Experimental example 1
The modified SAPO-11 molecular sieves provided in examples 1-4 were tested for relative crystallinity, based on 100% crystallinity of the commercial SAPO-11 molecular sieve raw powder in comparative example 1. Specifically, an X-ray diffractometer is adopted to measure the relative crystallinity of a sample, the peak areas of characteristic diffraction peaks within the range of 20.2-24.8 degrees of 2 theta are summed by Highscore software, and then the relative crystallinity is calculated, wherein the calculation formula is as follows:
relative crystallinity (%) - (sum of characteristic peak-to-peak areas of the sample ÷ mean value) ÷ (sum of characteristic peak-to-peak areas of the standard ÷ mean value) × 100%.
The results are shown in Table 1.
TABLE 1
Sample (I) | Relative degree of crystallinity,% |
SAPO-11 | 100 |
0.05M-SAPO-11 | 98 |
0.10M-SAPO-11 | 92 |
0.30M-SAPO-11 | 90 |
0.50M-SAPO-11 | 77 |
As can be seen from the data in Table 1, the modified SAPO-11 molecular sieves provided by examples 1-4 have a relative crystallinity of no less than 70%.
Experimental example 2
XRF characterization was performed on the modified SAPO-11 molecular sieves provided in examples 1-4 and on the commercial SAPO-11 molecular sieve raw powder in comparative example 1, and the characterization results are shown in Table 2.
TABLE 2 content of bulk elements in each sample
As can be seen from the data in Table 2, the SAPO-11 molecular sieves provided in examples 1-4 substantially maintained the relative aluminum content of the molecular sieves unchanged from the commercial SAPO-11 molecular sieve raw powder before modification. As the concentration of the alkali liquor increases, the relative content of aluminum does not change significantly, and the relative content of phosphorus decreases, so that it can be known that: in SAPO-11 molecular sieves, a concentration of alkali treatment will primarily remove phosphorus species, which will reduce the damage to the silicon islands and thus the strong acid sites.
Experimental example 3
The pore structure properties were separately performed on the modified SAPO-11 molecular sieves provided in examples 1-4 and on the commercial SAPO-11 molecular sieve raw powder in comparative example 1, and the results are shown in table 3.
Table 3 pore structure property data for each sample
Wherein: sBETIs the total specific surface area; sMicroIs the specific surface area of the micropores; sMesoIs the mesoporous specific surface area; vTotalIs the total pore volume; vMicroIs the micropore volume; vMesoIs the mesoporous volume.
As can be seen from the data in Table 3, the SAPO-11 molecular sieves provided in examples 1-4 have a significantly increased mesopore volume relative to the pore volume of the raw powder of the commercial SAPO-11 molecular sieve before modification. Therefore, the modification method provided by the invention realizes the introduction of the mesopores. The data of the experimental example 2 are combined to know that the modification method provided by the invention successfully introduces mesopores mainly by removing the framework phosphorus species.
Experimental example 4
NH was respectively applied to the modified SAPO-11 molecular sieves provided in examples 1 to 4 and to the commercial SAPO-11 molecular sieve raw powder in comparative example 13TPD spectrum test to analyze its acid properties, the results are shown in FIG. 6.
As can be seen from fig. 6, the weak acid strength and the strong acid strength of the modified SAPO-11 molecular sieves provided in examples 1 to 4 are both improved by a proper amount, which also illustrates that the modification method provided by the present invention reduces the damage to the silicon islands while introducing the mesopores.
Experimental example 5
The long-chain alkane hydrocracking/isomerization catalysts provided in comparative example 1 and example 1 were tested for performance in catalyzing long-chain alkane hydrocracking/isomerization reactions, respectively.
Testing one: the performance of the long-chain alkane hydrocracking/isomerization catalysts provided in comparative example 1 and example 1, respectively, in the process of catalyzing the hydrocracking/isomerization reaction of n-hexadecane hydrocarbon at 340 ℃, was tested on a fixed bed hydrogenation evaluation device, and the specific process was as follows:
1) dividing the catalyst to be evaluated into particles of 40-60 meshes before reaction, then accurately weighing 3g of the particles, filling the particles into the middle part of a stainless steel reaction tube with the inner diameter of 11mm, and continuously filling quartz sand of 20-40 meshes at the upper and lower positions of the filling position of the particles in the stainless steel reaction tube;
2) introducing hydrogen into the stainless steel reaction tube after the step 1) is finished to perform reduction treatment on the catalyst to be evaluated, wherein the reduction pressure is normal pressure, the reduction temperature is 400 ℃, the reduction time is 4H, and H is2The flow rate is 60 ml/min;
3) performing ten steps after the step 2) is finishedThe method comprises the following steps of (1) carrying out a hexahydro-cracking/isomerization reaction on hexaalkane, wherein the reaction conditions are as follows: the reaction temperature is 340 ℃, the reaction pressure is 6MPa, and the mass space velocity of the fed reaction raw materials is 2h-1The volume ratio of hydrogen to oil is 400: 1.
After the reaction was completed, the liquid product was analyzed off-line using an agilent 7890A gas chromatograph. And calculating the mass fraction of each component in the product through normalization quantification of chromatographic peaks. The yield of the liquid product is approximately expressed by the difference in mass between the amount of the reaction raw material fed and the amount of the reaction liquid product fed, and the loss part is the gas-phase product.
And calculating the conversion rate of the n-hexadecane and the distribution of each component in the product according to the liquid yield of the reaction product and the mass fraction of each component in the liquid product. The calculation method is as follows:
consider the case of gas loss:
mass fraction W of component i in the liquid producti=Ai÷ΣAi×100%
Yield of component i ═ W in the productiX liquid yield
Total conversion of n-hexadecane Cn16=(1-Wn16X liquid yield) x 100%
Wherein: a. theiIs the peak area of the component i in the liquid product in the chromatographic peak; sigma AiIs the sum of peak areas of all components in the liquid product in chromatographic peaks; wn16Is the peak area of normal hexadecane in the liquid product in the chromatographic peak.
The analysis of the liquid product alone was:
mass fraction W of component i in the liquid producti=Ai÷ΣAi×100%
Yield of component i ═ W in the producti
Conversion C of n-hexadecane in liquid productn16=(1-Wn16)×100%
Wherein: a. theiIs the peak area of the component i in the liquid product in the chromatographic peak; sigma AiIs the sum of peak areas of all components in the liquid product in chromatographic peaks; wn16The normal hexadecane in the liquid product is in the chromatographic peakPeak area of (a).
And (2) testing: the long-chain alkane hydrocracking/isomerization catalysts provided in comparative example 1 and example 1 were tested for their performance in catalyzing the hydrocracking/isomerization reaction of n-hexadecane hydrocarbon at 360 ℃, respectively, and test two was different from test one only in that the reaction temperature in step 3) was 360 ℃.
And (3) testing: the long-chain alkane hydrocracking/isomerization catalysts provided in comparative example 1 and example 1 were tested for their performance in catalyzing the hydrocracking/isomerization reaction of n-hexadecane hydrocarbon at 380 ℃, respectively, with test three being different from test one only in that the reaction temperature in step 3) was 380 ℃.
In the first test, the second test and the third test, the results of evaluating the catalytic performance of the long-chain alkane hydrocracking/isomerization catalysts provided by the comparative example 1 and the example 1 are shown in the tables 4 and 5; where, table 4 shows the distribution of the components in the total product and table 5 shows the distribution of the components in the liquid product.
TABLE 4 results of evaluation of hydrocracking/isomerization of n-hexadecane by catalyst
TABLE 5 distribution of components in liquid product after hydrocracking/isomerization reaction of catalyst vs. n-hexadecane
Wherein: n-C16Represents normal hexadecane; i-C16Represents isomeric hexadecane. Table 4 shows the conversion and yield calculated taking into account the gas loss. Table 5 shows the conversions and yields obtained for each component in the liquid product alone, without taking into account gas losses. For example: taking the reaction of Pt/SAPO-11 at 340 ℃ as an example, it can be seen from Table 5 that:
in the case where the loss of gas is not taken into account,
the conversion of n-hexadecane in the liquid product was 29.72%;
the proportion of unreacted n-hexadecane in the liquid product was 70.28%;
the yield of isomeric hexadecane in the liquid product is 24.57 percent;
c in the liquid product9-C15The yield of hydrocarbons was 3.75%;
c in the liquid product5-C8The yield of hydrocarbons was 1.19%;
considering the gas loss, the data is shown in table 4:
the total conversion of n-hexadecane was 1-70.28% x 83.66%, which was 41.21%;
the yield of isomeric hexadecane was 24.75% x 83.66%, which was 20.70%;
C9-C15the hydrocarbon yield was 3.75% x 83.66%, which was 3.14%;
C5-C8the hydrocarbon yield was 1.19% x 83.66%, which was 0.99%;
as is clear from tables 4 and 5, catalyst C provided in comparative example 1 was used9-C15The hydrocarbon yield was significantly lower than using the catalyst provided in example 1. The modification method of the SAPO-11 molecular sieve provided by the invention ensures that the relative content of aluminum is basically unchanged while introducing a large amount of mesopores during dephosphorization, so that the prepared modified SAPO-11 molecular sieve has larger mesopore volume and stronger acid strength, exposes more active sites for reaction, increases the contact chance of reactants and the active sites, and increases the cracking capability due to the increase of a proper amount of the acid strength, thereby realizing the C-type zeolite with high catalytic activity and high catalytic activity9-C15The increase in hydrocarbon yield.
In a word, the SAPO-11 molecular sieve prepared by the SAPO-11 molecular sieve modification method mainly removes phosphorus species when mesoporous is introduced, and the relative content of aluminum is basically kept unchanged, so that the damage to the acidity of the molecular sieve is reduced. Effectively realizes the increase of C yield in the hydrocracking/isomerization reaction of the n-hexadecane9-C15An isomeric hydrocarbon.
Claims (10)
1. A modification method of SAPO-11 molecular sieve comprises the following steps:
1) at the temperature of 30-90 ℃, the SAPO-11 molecular sieve is put into an alkali solution with the concentration of 0.05-1mol/L for alkali treatment for 0.3-2 h; wherein the alkali comprises at least one of sodium hydroxide, ammonia water, ethylamine, diethylamine, triethylamine, ethanolamine, diethanolamine and triethanolamine;
2) after the SAPO-11 molecular sieve subjected to alkali treatment is washed to be neutral, ammonium exchange treatment is carried out;
3) and (3) washing and drying the ammonium-exchanged SAPO-11 molecular sieve, and roasting to realize modification of the SAPO-11 molecular sieve.
2. The modification method according to claim 1, wherein the concentration of the alkali solution is 0.1 to 0.5 mol/L.
3. The modification method according to claim 1, wherein the base is sodium hydroxide.
4. The modification method according to claim 1, wherein the mass ratio of the SAPO-11 molecular sieve to the alkali solution is 1:40 to 1: 5.
5. The modification method according to claim 1, wherein the ammonium exchange medium used in the ammonium exchange treatment comprises at least one of ammonium chloride, ammonium sulfate, ammonium nitrate, and ammonium carbonate; ammonium chloride is preferred.
6. The modification method according to claim 1,
the temperature of the alkali treatment is 35-85 ℃;
the roasting temperature is 350-650 ℃; preferably 400-600 ℃;
the roasting time is 3-8 h.
7. A modified SAPO-11 molecular sieve prepared by a SAPO-11 molecular sieve modification method according to any one of claims 1 to 6; preferably, the modified SAPO-11 molecular sieve has a crystallinity of not less than 70%.
8. Use of the modified SAPO-11 molecular sieve of claim 7 in the preparation of a long paraffin hydrocracking/isomerization catalyst;
preferably, the long-chain alkane hydrocracking/isomerization catalyst is used for preparing C by hydrocracking/isomerizing long-chain alkane9-C15Catalysts for isoparaffins;
preferably, the long chain alkane is n-hexadecane.
9. A long-chain alkane hydrocracking/isomerization catalyst, wherein the catalyst takes the modified SAPO-11 molecular sieve as claimed in claim 7 as a carrier;
preferably, the active component of the catalyst is Pt; more preferably, the catalyst is prepared by impregnating H with a catalyst2PtCl6Dipping the modified SAPO-11 molecular sieve of claim 7, and roasting at 400-600 ℃ for 3-8 h.
10. The catalyst of claim 9, wherein the mass of Pt is 0.3-1.0% of the mass of the molecular sieve.
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Publication number | Priority date | Publication date | Assignee | Title |
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CN114620742A (en) * | 2020-12-10 | 2022-06-14 | 中国科学院大连化学物理研究所 | Preparation method of hierarchical pore molecular sieve |
CN114620742B (en) * | 2020-12-10 | 2023-09-15 | 中国科学院大连化学物理研究所 | Preparation method of hierarchical pore molecular sieve |
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