A synthetic bundle of filamentous low-silica ZSM-48 zeolite from FCC spent catalyst and method of making same

Abstract

The application discloses a kind of FCC waste catalyst synthesis bundle filamentous low-silicon-aluminum ratio ZSM-48 molecular sieve and preparation method thereof, the ZSM-48 bundle filamentous molecular sieve is prepared by hydrothermal crystallization reaction with template agent, auxiliary agent, using FCC waste catalyst particles as part of raw material, in the bundle filamentous molecular sieve crystal obtained, the diameter of bundle filament is 1~2 μm, the length of bundle filament is 2~20 μm, the diameter of single filament in bundle filament is 10~20 nm, bundle filament crystal presents stacking and good dispersion, the molar ratio of silica and alumina in molecular sieve is in the range of 24~100.The ZSM-48 molecular sieve can be prepared into molecular sieve catalyst and applied to paraffin-containing raw material dewaxing catalytic reaction, can also be applied to n-alkane hydroisomerization, long-chain alkane hydrocracking, C4-olefin cracking, xylene isomerization, methanol to gasoline (MTG), methanol to hydrocarbon and synthesis gas (CO+H2) direct conversion into gasoline and other fields, with good application prospect.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of FCC waste catalyst synthesis bundle filamentous low-silicon aluminum ratio ZSM-48 molecular sieve and its preparation method, belong to inorganic material synthesis technical field. BACKGROUND

[0002] ZSM-48 molecular sieve is a new type of high-silicon molecular sieve synthesized by U.S.Mobil company in early 1980s, with MRE topological structure one-dimensional ten-membered ring opening non-penetrating two-dimensional linear pore, which is connected by 5-membered ring between pore, and its ideal pore diameter is 0.53nm×0.56nm.Due to its unique one-dimensional ten-membered ring straight-through pore structure and suitable acid amount, it is widely used in n-alkane hydroisomerization, long-chain alkane hydrocracking, C4-olefin cracking, xylene isomerization, methanol to gasoline (MTG), methanol to hydrocarbon and synthesis gas (CO+H2) direct conversion to gasoline, etc.In n-alkane hydroisomerization reaction process, isomerization reaction of n-alkane mainly occurs in ten-membered ring opening of carrier ZSM-48 molecular sieve, so that acid center located in opening is beneficial to the performance improvement of isomerization reaction, and acid in pore due to strong acid and its own diffusion restriction in pore, will lead to cracking side reaction, thereby affecting isomerate yield.Catalytic reaction, but the current conventional ZSM-48 molecular sieve has problems of high silicon-aluminum ratio, low acid amount and high synthesis cost, therefore, it has very important practical significance to develop a low-cost low-silicon aluminum ratio ZSM-48 molecular sieve synthesis method.

[0003] US5075269 discloses that ZSM-48 molecular sieve is synthesized with water glass and silica sol as silicon source, aluminum sulfate and sodium metaaluminate as aluminum source, and bromide hexamethyl ammonium as template agent, and the lowest silicon-aluminum ratio of ZSM-48 molecular sieve can be as low as 170.CN112142066A discloses that ZSM-48 molecular sieve with silicon-aluminum ratio ranging from 80 to 600 is obtained after aging and hydrothermal crystallization by using a double-template agent consisting of HMDA and CTAC.CN101330976B discloses that ZSM-48 molecular sieve with silicon-aluminum ratio of 70 to 110 is obtained by using hexamethyl ammonium salt as organic organic template agent;US7625478 and US7482300 disclose that ZSM-48 with expensive bromide hexamethyl ammonium as template agent and ZSM-48 as seed crystal can be obtained at a feeding silicon-aluminum ratio of about 100, and ZSM-48 with silicon-aluminum ratio of about 100 can be obtained after crystallization for 48 hours, and the lowest SiO2 / Al2O3 molar ratio of ZSM-48 is about 80, but there are problems of high cost and serious pollution.

[0004] FCC catalyst is usually composed of zeolite Y ion-exchanged with rare earth elements (lanthanum or cerium), an inert matrix of kaolin, and a binder mixed with silica and alumina. During the FCC reaction process, the production of coke deposits will cause the catalyst pore to be blocked and the active site to be inactivated. The mainstream disposal method of FCC spent catalyst is collection and landfill, which will cause secondary pollution of soil and groundwater. Although the extraction of valuable metals from FCC spent catalyst by hydrometallurgy and other methods can obtain certain economic benefits, it will still produce secondary hazardous solid waste. This FCC spent catalyst contains a large amount of silicon and aluminum elements, especially the Y or USY molecular sieve structure can provide tetramer ring and hexamer ring secondary structural units, which are easy to recombine into the unit structure of ZSM-48 molecular sieve during the crystallization process, forming a special morphology of low silicon aluminum ratio characteristics, not only making the resources can be fully utilized, but also reducing the synthesis cost, obtaining a special molecular sieve product with better performance. SUMMARY

[0005] The purpose of the present application is to overcome the problems of poor relative crystallinity of ZSM-48 molecular sieve and inability to obtain low silicon aluminum ratio in the prior art, and to provide a FCC spent catalyst as a silicon aluminum source for synthesizing a bundle filamentous low silicon aluminum ratio ZSM-48 molecular sieve and a preparation method thereof. The preparation method of the ZSM-48 molecular sieve can re-crystallize most of the silicon aluminum source in the FCC spent catalyst, is simple to operate, has high production efficiency, is conducive to industrialized production, and the obtained ZSM-48 molecular sieve has high relative crystallinity, and when applied to hydrocarbon oil hydrogenation isomerization reaction, can obtain higher product yield.

[0006] The ZSM-48 molecular sieve in the prior synthesis technology generally presents an aggregated state and has a large grain size. When the ZSM-48 molecular sieve is used for catalytic reaction, the diffusion resistance of reactant or product molecules on the surface of the molecular sieve crystal is large, carbon deposition is easy to occur, and it is difficult to be applied in large scale in industry. Therefore, it is of great significance to synthesize a ZSM-48 molecular sieve with single crystal phase, small particle size, large specific surface area and non-aggregated state morphology.

[0007] In order to solve the above technical problems, the technical scheme of the present application is as follows: a bundle filamentous ZSM-48 molecular sieve, the diameter of the bundle filament is 1-2 μm, the length of the bundle filament is 2-20 μm, the diameter of the single filament in the bundle filament is 10-20 nm, and the molar ratio of silicon oxide to aluminum oxide is 24-100, and the preparation steps thereof include:

[0008] 1) FCC spent catalyst particles are crushed into small particles of 80-120 mesh, calcined at 600-1000 ℃ for 1-10 hours, the calcined solid is treated with 0.1-1.0 mol / L hydrochloric acid, sulfuric acid or nitric acid solution according to solid-liquid ratio 1:(4-10) for 1-5 hours of ultrasonic immersion, filtered, washed with deionized water to pH 6-8, and dried to obtain a silicon-aluminum powder with a dry basis of ≥75%.

[0009] 2) The silicon-aluminum powder obtained in 1) is mixed with a silicon source, an alkali source, and deionized water, aged at 80-120 ℃ for 12-36 hours, an organic template OSDA and an additive AIDS are added, and crystallized at 150-200 ℃ for 24-120 hours, and the obtained bundle-shaped ZSM-48 molecular sieve is recovered after quenching.

[0010] Silicon is calculated as silicon oxide, aluminum is calculated as aluminum oxide, alkali source is calculated as sodium oxide, n SiO2 / n Al2O3 is 20-100, n NaO2 / n SiO2 is 0.03-0.08, n H2O / n SiO2 is 15-60, n OSDA / n SiO2 is 0.03-0.3, n AIDS / n SiO2 is 0.001-0.01.

[0011] The organic template is [(R1)3N + (CH2)n N + (R2)3]·2X - , R1 and R2 are each independently C1-C5 linear alkyl, n is an integer of 3-10, and X - is at least one of OH - , Cl - , Br - , or I - .

[0012] The additive is any one or several of ethanolamine, N,N-dimethylethanolamine, N-methyl monoethanolamine, N-ethylethanolamine, N,N-dimethyl isopropanolamine.

[0013] Some specific bundle-shaped ZSM-48 molecular sieves, R1 and R2 are each independently methyl, ethyl, n-propyl or n-butyl, n is an integer of 4-8, and X is any one of OH - , Cl - , Br - , or I - .

[0014] Some specific fascicular ZSM-48 molecular sieves, R1 and R2 are methyl, X is OH - or Br - .

[0015] Some specific fascicular ZSM-48 molecular sieves, the silicon source is one or several of silica sol, water glass, C-type silica gel, macroporous silica gel, coarse-pore silica gel, fine-pore silica gel, white carbon black, chromatographic silica gel, diatomite and organosilane.

[0016] Some specific fascicular ZSM-48 molecular sieves, the organosilane is any one of methylorthosilicate, ethylorthosilicate, propylorthosilicate, butylorthosilicate, ethyltriethoxysilane, vinyltriethoxysilane, triethoxysilane, propyltrimethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, methyldiethoxysilane, methyltriethoxysilane, trimethoxysilane, propyltriethoxysilane, methylvinyl dimethoxysilane, methyl dimethoxysilane, isobutyltriethoxysilane, diisopropyl dimethoxysilane, isobutyl isopropyl dimethoxysilane.

[0017] Some specific fascicular ZSM-48 molecular sieves, the organosilane is any one of methylorthosilicate, ethylorthosilicate, propylorthosilicate, butylorthosilicate, trimethoxysilane, triethoxysilane.

[0018] Some specific fascicular ZSM-48 molecular sieves, n SiO2 / n Al2O3 is 25-100, n NaO2 / n SiO2 is 0.035-0.08, n H2O / n SiO2 is 15-55, n OSDA / n SiO2 is 0.035-0.25, n AIDS / n SiO2 is 0.0015-0.0095.

[0019] Some specific fascicular ZSM-48 molecular sieves, the molar ratio of silicon oxide to aluminum oxide in the molecular sieve ranges from 24 to 100.

[0020] The use of the above-mentioned fascicular ZSM-48 molecular sieves in hydrocarbon oil hydroisomerization reactions.

[0021] A process for synthesizing fascicular low-silicon-to-aluminum ratio ZSM-48 molecular sieves from FCC spent catalyst, the preparation steps are as follows:

[0022] 1) FCC waste catalyst particles are crushed and sieved to obtain 80-120 mesh small particles, the carbon deposition and attached organic matter are removed by calcining at 600-1000 DEG C for 1-10 hours, and the solid product after calcination is treated by ultrasonic immersion with 0.1-1.0 mol / L concentration of hydrochloric acid or sulfuric acid or nitric acid solution according to the solid-liquid ratio of 1:(4-10) for 1-5 hours, the recovered material is filtered and washed with deionized water until the pH value is 6-8, and the filter cake is dried at 100-150 DEG C to obtain a dry base of ≥75% silicon aluminum powder for standby.

[0023] 2) The silicon aluminum powder obtained in 1) is mixed with a silicon source, an alkali source and deionized water, and the n SiO2 / n Al2O3 ratio in the slurry is 20-100, the n NaO2 / n SiO2 ratio is 0.03-0.08, and the n H2O / n SiO2 ratio is 15-60, and the mixture is aged at 80-120 DEG C for 12-36 hours in a hydrothermal synthesis kettle, and an organic template (OSDA) and an aid (AIDS) are added to the synthesis system, so that the n OSDA / n SiO2 ratio is in the range of 0.03-0.3, the n AIDS / n SiO2 ratio is in the range of 0.001-0.01, and the crystallization is carried out at 150-200 DEG C for 24-120 hours, and the bundle-shaped low-silicon aluminum ratio ZSM-48 molecular sieve is obtained after quenching recovery.

[0024] The ZSM-48 molecular sieve synthesized above is exchanged with 0.1-1.0 mol / L of an ammonium ion solution according to the solid-liquid ratio of 1:5-10 at 60-100 DEG C to prepare a H-type ZSM-48 molecular sieve, which can be used as a catalyst active component, loaded with metal components and binders to prepare a catalyst for application.

[0025] Further, the ZSM-48 molecular sieve can be prepared into a molecular sieve catalyst and applied to dewaxing catalytic reactions of a paraffin-containing raw material, and can also be applied to n-alkane hydroisomerization, long-chain alkane hydrocracking, C4-olefin cracking, xylene isomerization, methanol-to-gasoline (MTG), methanol-to-hydrocarbon and direct conversion of synthesis gas (CO+H2) into gasoline, etc., and has a good application prospect.

[0026] The ZSM-48 molecular sieve synthesized above is exchanged with 0.1-1.0 mol / L of an ammonium ion solution according to the solid-liquid ratio of 1:5-10 at 60-100 DEG C to prepare a H-type ZSM-48 molecular sieve, which can be used as a catalyst active component, loaded with metal components and binders to prepare a catalyst for application. The beneficial effects of the present application are: the waste FCC catalyst is used as a silicon aluminum source, a specific low-cost organic template is used to synthesize a single crystal phase, a long bundle-shaped ZSM-48 molecular sieve with good dispersibility in a short time, the synthesis cost is reduced, and the synthesis efficiency is improved. The present application synthesizes a low-silicon aluminum ratio ZSM-48 molecular sieve with a silicon aluminum ratio in the range of 24-100, the unit molecular sieve contains more acid, and the bottleneck restricting the wide application of the ZSM-48 molecular sieve is broken through. Attached Figure Description

[0027] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0028] Figure 1 This is the XRD phase diagram of the ZSM-48 molecular sieve synthesized in Example 1;

[0029] Figure 2 This is the XRD phase diagram of the ZSM-48 molecular sieve synthesized in Example 2;

[0030] Figure 3 This is the XRD phase diagram of the ZSM-48 molecular sieve synthesized in Example 3;

[0031] Figure 4 This is the XRD phase diagram of the synthesized ZSM-48 molecular sieve in Example 4;

[0032] Figure 5 This is a SEM analysis image of the synthesized ZSM-48 molecular sieve in Example 1;

[0033] Figure 6 This is a SEM analysis image of the synthesized ZSM-48 molecular sieve in Example 2;

[0034] Figure 7 This is a SEM analysis image of the synthesized ZSM-48 molecular sieve in Example 3;

[0035] Figure 8 This is a SEM analysis image of the synthesized ZSM-48 molecular sieve in Example 4. Detailed Implementation

[0036] The embodiments and comparative examples further illustrate the implementation methods and effects of the present invention, but the scope of protection of the present invention is not limited to the contents listed in the embodiments.

[0037] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0038] The samples were characterized by XRD using a PANalytical Xpert Pro diffractometer with Cu Kα rays (λ = 0.15406 nm), tube voltage 45 kV, tube current 40 mA, scan range 5°~55°, step 0.026°, and each step 17.34 ms.

[0039] The composition of the sample was determined by using a PANalytical Axios series X-ray fluorescence spectrometer (XRF), the sample was prepared by tabletting method, the measurement conditions were end-window rhodium target, tube voltage was 50 kV, and tube current was 50 mA.

[0040] The sample was detected by using a HITACHI thermal field emission scanning electron microscope SU5000 in a backscattering mode, the beam current was adjusted to "standard", the acceleration voltage was selected to be 10 kV, and the magnification was 5~50 k.

[0041] The pore volume of the sample was determined on a Micromeritics ASAP2460 physical adsorption instrument. Before testing, the sample was vacuum treated at 200°C for 6 h, and then N2 adsorption and desorption isotherm determination was carried out at liquid nitrogen temperature. The micropore volume of the sample was calculated by t-plot method.

[0042] The relative crystallinity was calculated by the following method: the XRD of the sample to be tested and the standard sample were tested respectively, the characteristic peak area was calculated, and then the relative crystallinity of the sample to be tested was calculated by the following formula,

[0043] Relative crystallinity = S 18-28° (sample to be tested) / S 18-28° (sample) x 100%;

[0044] S 18-28° (sample to be tested) is the area of the characteristic peak of the sample to be tested at 2θ = 18-28°, and S 18-28° (sample) is the area of the characteristic peak of the standard sample at 2θ = 18-28°.

[0045] A HITACHI inductively coupled plasma mass spectrometer ICPE-9820 was used, bidirectional observation was performed, the wavelength range of the spectrometer was 167-800 nm, the automatic sample injector was 68-bit, the vacuum degree was <10 Pa. The plasma gas was 8~20 L / min; the auxiliary gas was 0.5~2 L / min; the carrier gas was 0~2 L / min. The output stability was within ±0.1%.

[0046] The compositions of the FCC spent catalysts of Petrochemical Company A, Petrochemical Company B, Petrochemical Company C, Petrochemical Company D and Petrochemical Company E used in the following examples are shown in Table 1:

[0047] Table 1 Composition of FCC spent catalysts from different sources

[0048]

[0049] Example 1: Z48-1

[0050] 1) FCC spent catalyst particles of Petrochemical Company A were crushed and sieved to obtain 80-120 mesh small particles, which were calcined at 650°C for 10 hours to remove coke and organic matter. The calcined solid product was treated by ultrasonic immersion with 0.15 mol / L hydrochloric acid solution at a solid-liquid ratio of 1:10 at 60°C for 2 hours. The recovered material was filtered and washed with deionized water until the pH value was 6-8. The filter cake was dried at 120°C for 24 hours. The dry basis of the silicon-aluminum powder was 82%.

[0051] 2) 50.0 g of the silicon-aluminum material obtained in 1) was mixed with silica sol (Na2O%=0.11%, SiO2%=30.16%), NaOH (content 99%) and deionized water. After mixing, the n SiO2 / n Al2O3 =25, n NaO2 / n SiO2 =0.035 in a polytetrafluoroethylene liner at 100°C for 12 hours. The mixture was added with [(CH3)3N + (CH2)6N + (CH3)3]·2OH - (OSDA for short) and the auxiliary ethanolamine (AIDS for short), so that the nOSDA / nSiO2in the synthesis system was 0.035, n AIDS / n SiO2 =0.0075, n H2O / n SiO2 =20. Then the liner was covered and placed in a Parr Steel autoclave reactor, and then the autoclave was placed in a static condition and heated to 165°C for crystallization for 96 hours. The solid product was recovered by quenching centrifugation, washed with deionized water and dried at 120°C to obtain the solid product.

[0052] The obtained product was analyzed by powder XRD and SEM. The XRD pattern of the original powder after synthesis is shown in Figure 1 and is consistent with the product as pure ZSM-48 molecular sieve. The SEM image of the product is shown in Figure 5 , which presents a bundle filament morphology, wherein the diameter of the bundle filament is 1-2 μm, the diameter of the single filament is 12-20 nm, and the length of the bundle filament is 3-12 μm, and the dispersion is good. The n SiO2 / n Al2O3 molar ratio of the product was 24.8. The specific surface area and relative crystallinity data by BET and XRD analysis are shown in Table 1.

[0053] Example 2: Z48-2

[0054] 1) FCC spent catalyst particles of Petrochemical Company B were crushed and sieved to obtain 80-120 mesh small particles, which were calcined at 750°C for 8 hours to remove coke and organic matter. The calcined solid product was treated with 0.25 mol / L sulfuric acid solution at 40°C for 3 hours at a solid-liquid ratio of 1:8 under ultrasonic immersion. The recovered material was filtered and washed with deionized water until the pH value was 6-8. The filter cake was dried at 110°C for 36 hours. The dry basis of the silicon-aluminum powder was 83%.

[0055] 2) 50.0 g of the silicon-aluminum material obtained in 1) was mixed with water glass (Na2O%=10.68%, SiO2%=29.7%), NaOH (content 99%) and deionized water. After mixing, the n SiO2 / nAl2O3 =40, n NaO2 / nSiO2 =0.045, was static aged in a polytetrafluoroethylene liner at 80°C for 24 hours. The mixture was added with [(CH3)3N + (CH2)4N + (CH3)3]·2OH - (OSDA for short) and the auxiliary N,N-dimethyl ethanolamine (AIDS for short), so that the n OSDA / n SiO2 =0.045, n AIDS / n SiO2 =0.0055, n H2O / n SiO2 =15 The liner was then covered and placed in a Parr Steel autoclave reactor, and then the autoclave was placed in a static condition and heated to 175°C for crystallization for 72 hours. The solid product was recovered by quenching and centrifugation, washed with deionized water and dried at 105°C to obtain the solid product.

[0056] The product was analyzed by powder XRD and SEM. The XRD pattern of the original powder after synthesis is shown in Figure 2 and is consistent with the product being pure ZSM-48 molecular sieve. The SEM image of the product is shown in Figure 6 , which presents a bundle filament morphology, wherein the diameter of the bundle filament is 1-2 μm, the diameter of the single filament is 10-20 nm, and the length of the bundle filament is 2-18 μm, with good dispersity. The n SiO2 / n Al2O3 molar ratio of the product was 36.5. The specific surface area and relative crystallinity data by BET and XRD analysis are shown in Table 1.

[0057] Example 3: Z48-3

[0058] 1) FCC spent catalyst particles of Petrochemical Company C were crushed and sieved to obtain 80-120 mesh small particles, which were calcined at 850°C for 6 hours to remove coke and organic matter. The calcined solid product was treated with 0.45 mol / L nitric acid solution at 25°C for 5 hours at a solid-liquid ratio of 1:6 by ultrasonic immersion. The recovered material was filtered and washed with deionized water until the pH value was 6-8. The filter cake was dried at 130°C for 12 hours, and the dry basis of the silicon-aluminum powder was 85%.

[0059] 2) 50.0 g of the silicon-aluminum material obtained in 1) was mixed with C-type silica gel (SiO2%=95.18%), NaOH (content 99%) and deionized water. After mixing, n SiO2 / n Al2O3 =60, n NaO2 / n SiO2 =0.045, the mixture was statically aged at 120°C in a polytetrafluoroethylene liner for 12 hours. The mixture was added with [(CH3)3N + (CH2)8N + (CH3)3]·2OH - (OSDA for short) and the auxiliary N-methyl monoethanolamine (AIDS for short), so that n OSDA / n SiO2 =0.08, n AIDS / n SiO2 =0.0085, n H2O / n SiO2 =35. Then the liner was covered and placed in a Parr Steel autoclave reactor, and then the autoclave was placed in a static condition and heated to 185°C for crystallization for 60 hours. The solid product was recovered by quenching and centrifugation, washed with deionized water and dried at 115°C to obtain the solid product.

[0060] The obtained product was analyzed by powder XRD and SEM. The XRD pattern of the original powder after synthesis is shown in Figure 3 and is consistent with the product as pure ZSM-48 molecular sieve. The SEM image of the product is shown in Figure 7 , which presents a bundle filament morphology, wherein the diameter of the bundle filament is 1-2 μm, the diameter of the single filament is 10-20 nm, and the length of the bundle filament is 4-20 μm, and the dispersion is good. The n SiO2 / n Al2O3 molar ratio of the product was 58.4. The specific surface area and relative crystallinity data by BET and XRD analysis are shown in Table 1.

[0061] Example 4: Z48-4

[0062] 1) FCC spent catalyst particles from Petrochemical Company D were crushed and sieved to obtain 80-120 mesh small particles, which were calcined at 950°C for 4 hours to remove coke and organic matter. The calcined solid product was treated with 0.85 mol / L hydrochloric acid solution at 25°C for 2 hours at a solid-to-liquid ratio of 1:4 by ultrasonic immersion. The recovered material was filtered and washed with deionized water until the pH value was 6-8. The filter cake was dried at 115°C for 24 hours. The dry basis of the silicon-aluminum powder was 81%.

[0063] 2) 50.0 g of the silicon-aluminum material obtained in 1) was mixed with ethyl silicate (TEOS > 99%), NaOH (content 99%), and deionized water. After mixing, the n SiO2 / n Al2O3 = 80, n NaO2 / n SiO2 = 0.065 in a polytetrafluoroethylene liner at 105°C for 24 hours. The mixture was added with [(CH3)3N + (CH2)6N + (C2H5)3] · 2OH - (OSDA for short) and the auxiliary N-ethyl ethanolamine (AIDS for short), so that the n OSDA / n SiO2 = 0.15, n AIDS / n SiO2 = 0.0015, n H2O / n SiO2 = 40. Then the liner was covered and placed in a Parr Steel autoclave reactor, and then the autoclave was placed in a static condition and heated to 195°C for crystallization for 36 hours. The solid product was recovered by quenching and centrifugation, washed with deionized water and dried at 120°C to obtain the solid product.

[0064] The product was analyzed by powder XRD and SEM. The XRD pattern of the original powder after synthesis is shown in Figure 4 and is consistent with the product being pure ZSM-48 molecular sieve. The SEM image of the product is shown in Figure 8 , which presents a bundle filament morphology, wherein the diameter of the bundle filament is 1-2 μm, the diameter of the single filament is 15-20 nm, and the length of the bundle filament is 3-16 μm, and the dispersion is good. The n SiO2 / n Al2O3 molar ratio of the product was 76.8. The specific surface area and relative crystallinity data by BET and XRD analysis are shown in Table 1.

[0065] Example 5: Z48-5

[0066] 1) FCC spent catalyst particles from Petrochemical Company E were crushed and sieved to obtain 80-120 mesh small particles, which were calcined at 1000 °C for 2 hours to remove coke and organic matter. The calcined solid product was treated with 0.35 mol / L sulfuric acid solution at 20 °C for 3 hours at a solid-to-liquid ratio of 1:6 with ultrasonic immersion. The recovered material was filtered and washed with deionized water until the pH value reached 6-8. The filter cake was dried at 100 °C for 24 hours. The dry basis of the silicon-aluminum powder was 78%.

[0067] 2) 50.0 g of the silicon-aluminum material obtained in 1) was mixed with trimethoxysilane (purity > 99%), NaOH (content 99%), and deionized water. After mixing, n SiO2 / n Al2O3 = 100, n NaO2 / n SiO2 = 0.078 in a polytetrafluoroethylene liner at 105 °C for 36 hours of static aging. The mixture was added with [(CH3)3N + (CH2)6N + (CH3)3] · 2Br - (OSDA for short) and the auxiliary N, N-dimethylisopropanolamine (AIDS for short), so that n OSDA / n SiO2 = 0.25, n AIDS / n SiO2 = 0.0095, n H2O / n SiO2 = 55. The liner was then covered and placed in a Parr Steel autoclave reactor, which was then heated to 155 °C under static conditions for crystallization for 120 hours. The solid product was recovered by quenching and centrifugation, washed with deionized water, and dried at 120 °C to obtain the solid product.

[0068] The product was analyzed by powder XRD, and the results were consistent with the pure ZSM-48 molecular sieve phase. XRF analysis of the product showed a n SiO2 / n Al2O3 molar ratio of 97.3. BET and XRD analysis of the specific surface area and relative crystallinity data are shown in Table 1.

[0069] Comparative Example 1: Preparation of Molecular Sieve VS-1

[0070] Aluminum sulfate, hexamethonium bromide (HMBr), potassium hydroxide, deionized water were mixed and stirred for 30 min, then silica sol was added. The amount ratio of various substances in the mixed solution was n (Al2O3): (HMBr): n (Na+): n (H2O): n (SiO2) = 0.01: 0.03: 0.3: 5: 1. The mixture was transferred into a crystallization kettle and crystallized at 80°C for 24 h, then the temperature was increased to 180°C and crystallized for 48 h. After crystallization, the product was filtered and dried at 120°C for 6 h. The sample was calcined at 600°C for 4 h to obtain ZSM-48 molecular sieve, which was named VS-1. The XRF analysis results, specific surface area and relative crystallinity data are shown in Table 1.

[0071] Comparative Example 2: Preparation of molecular sieve VS-2 according to the preparation method of patent CN17963939A

[0072] 1 g of sodium hydroxide was weighed into 60 g of deionized water, stirred until completely dissolved, then 0.16 g of sodium aluminate (Al2O3=39.95%, Na2O=31.15%) was added to the mixed solution, stirred for one hour, then 1.2 g of urea was added until completely dissolved, then 6.5 g of hexamethonium bromide was added, and stirred vigorously for one hour, finally 15 g of silica sol (SiO2=40wt%, Na2O=0.11%) was added dropwise. The gel mixture was placed at room temperature for dynamic aging for 12 h, then transferred into a high gravity crystallization device, set the rotation speed to 1000 rpm, the temperature to 170°C, and crystallized for 72 h. After cooling, washing and drying, the ZSM-48 molecular sieve raw powder was obtained. The ZSM-48 molecular sieve raw powder was placed in a muffle furnace and calcined at 550°C for 3 h to remove the template agent, and then the ZSM-48 molecular sieve was obtained. The product was a pure phase ZSM-48 molecular sieve by X-ray diffraction (XRD), the silicon-aluminum ratio n SiO2 / n Al2O3 =117, and the molecular sieve was named VS-2. The XRF analysis results, specific surface area and relative crystallinity data are shown in Table 2.

[0073] Comparative Example 3: Preparation of molecular sieve VS-3

[0074] The preparation process, silicon-aluminum source and example 1 were the same, except that the FCC waste catalyst particles of petrochemical company A were crushed and sieved to obtain 80-120 mesh small particles, calcined at 650°C for 10 hours to remove carbon and attached organic matter, without subsequent acid ultrasonic treatment, and without adding the auxiliary agent ethanolamine. After mixing, the slurry was statically aged at 100°C for 12 hours, and crystallized at 65°C for 96 hours. The product had a silicon-aluminum ratio n SiO2 / n Al2O3 =102, and the molecular sieve was named VS-3.

[0075] Table 2 Catalyst performance parameters

[0076]

[0077] Test examples

[0078] Take 100 g of the molecular sieve in Examples 1-5 and Comparative Examples 1-3 respectively and 100 g of alumina, mix them thoroughly in a conical mixer, then introduce the mixture into a double-screw extruder produced in Weihai, Shandong, to obtain a φ2*4 mm cylindrical catalyst precursor, dry it at 120℃ for 24 hours, and calcine it at 540℃ for 6 hours to obtain the carrier. The mass fraction of the molecular sieve in the carrier is 50% by calculation.

[0079] Pour 1 g of dichlorotetraammine platinum (containing 55.8% of Pt by mass) into 100 g of deionized water, and stir until uniform. Pour 100 g of the carrier into the above solution, and immerse it at room temperature for 4 hours. Then, dry the above catalyst precursor at 120℃ for 4 hours. Next, calcine it in a stream of air at a temperature of 450℃ for 4 hours. The semi-finished catalyst is then reduced in a hydrogen atmosphere at 400℃ for 4 hours to obtain the catalyst. The catalysts in Test Examples 1-5 are named ISOC-1 to ISOC-5 respectively, and the catalysts obtained in Comparative Test Examples 1-3 are named VSC-1, VSC-2, and VSC-3 respectively.

[0080] The above catalysts are evaluated by the following evaluation method:

[0081] Put 50 g of the catalyst into a high-pressure hydrogenation reactor. Pour the hydrocracking tail oil feedstock into the reactor from top to bottom to react, and the reaction conditions are shown in Table 3 below. After the reaction is completed, collect the total liquid product, calculate the liquid yield, and then distill the liquid product to remove the light components less than 420 degrees, collect the components greater than 420 degrees, and calculate the product yield, and the results are shown in Table 4.

[0082] Table 3 List of reaction conditions

[0083]

[0084] Table 4 List of evaluation results of catalytic reaction at 330℃

[0085]

[0086] As can be seen from the results in Table 2, the ZSM-48 molecular sieve synthesized by the present application has a lower Si / Al ratio of less than 100, and the ZSM-48 molecular sieve obtained has a higher relative crystallinity and BET specific surface area. As can be seen from Tables 3 and 4, the hydrogen isomerization catalysts further prepared can obtain a higher product yield in the hydroisomerization reaction of hydrocarbon oil.

[0087] The above-mentioned embodiments are only for illustrating the technical concept and characteristics of the present application, and the purpose is to enable those skilled in the art to understand the content of the present application and to implement it, and cannot limit the protection scope of the present application. Any equivalent changes or modifications made according to the spirit and essence of the present application shall be covered within the protection scope of the present application.

Claims

1. A bundled ZSM-48 molecular sieve, characterized in that, The ZSM-48 bundled filamentous molecular sieve crystal has a bundled filament diameter of 1~2μm, a bundled filament length of 2~20μm, a single filament diameter of 10~20nm, and a silicon oxide to aluminum oxide molar ratio of 24~100. Its preparation steps include: 1) Crush the FCC waste catalyst particles into small particles of 80~120 mesh, calcine them at 600~1000 ℃ for 1~10 hours, and then ultrasonically soak the calcined solid in 0.1~1.0 mol / L hydrochloric acid, sulfuric acid or nitric acid solution at a solid-liquid ratio of 1: (4~10) for 1~5 hours. After filtration and washing with deionized water until the pH value reaches 6~8, dry to obtain silicon-aluminum powder with a dry basis of ≥75%; 2) The silicon-aluminum powder obtained in 1) is mixed with silicon source, alkali source and deionized water, and aged at 80~120℃ for 12~36 hours. Organic template agent OSDA and auxiliary agent AIDS are added, and crystallization is carried out at 150~200℃ for 24~120 hours. After quenching and recovery, the bundled ZSM-48 molecular sieve is obtained. Silicon is calculated as silicon dioxide, aluminum as aluminum oxide, alkali source as sodium oxide, and n in the reaction mixture. SiO2 / n Al2O3 The range is 20 to 100, n NaO2 / n SiO2 The value is between 0.03 and 0.08, n H2O / n SiO2 The value is 15~60, n OSDA / n SiO2 The value is 0.03~0.3, n AIDS / n SiO2 The value is between 0.001 and 0.

01. The organic template agent is [(R1)3N] + (CH2)n N + (R2)3]·2X - R1 and R2 are each independently a C1-C5 straight-chain alkyl group, n is an integer from 3 to 10, and X - For OH - Cl - ,Br - I - At least one of them; The adjuvant is any one or more of ethanolamine, N,N-dimethylethanolamine, N-methylmonoethanolamine, N-ethylethanolamine, and N,N-dimethylisopropanolamine.

2. The bundled ZSM-48 molecular sieve according to claim 1, characterized in that, R1 and R2 are each independently methyl, ethyl, n-propyl, or n-butyl, n is an integer from 4 to 8, and X is OH. - Cl - ,Br - Or I - Any one of them.

3. The bundled ZSM-48 molecular sieve according to claim 2, characterized in that, R1 and R2 are methyl groups, and X is an OH group. - Or Br - .

4. The bundled ZSM-48 molecular sieve according to any one of claims 1-3, characterized in that, The silicon source is one or more of the following: silica sol, water glass, type C silica gel, macroporous silica gel, coarse-pore silica gel, fine-pore silica gel, silica fume, chromatography silica gel, diatomaceous earth, and organosilanes.

5. The bundled ZSM-48 molecular sieve according to claim 4, characterized in that, The organosilane is any one of methyl orthosilicate, ethyl orthosilicate, propyl orthosilicate, butyl orthosilicate, ethyltriethoxysilane, vinyltriethoxysilane, triethoxysilane, propyltrimethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, methyldiethoxysilane, methyltriethoxysilane, trimethoxysilane, propyltriethoxysilane, methylvinyldimethoxysilane, methyldimethoxysilane, isobutyltriethoxysilane, diisopropyldimethoxysilane, and isobutylisopropyldimethoxysilane.

6. The bundled ZSM-48 molecular sieve according to claim 5, characterized in that, The organosilane is any one of methyl orthosilicate, ethyl orthosilicate, propyl orthosilicate, butyl orthosilicate, trimethoxysilane, and triethoxysilane.

7. The bundled ZSM-48 molecular sieve according to any one of claims 1-3, characterized in that, n in the reaction mixture SiO2 / n Al2O3 The range is 25~100, n NaO2 / n SiO2 The value is 0.035~0.08, n H2O / n SiO2 The range is 15~55, n OSDA / n SiO2 The value is 0.035~0.25, n AIDS / n SiO2 The value ranges from 0.0015 to 0.0095.

8. The application of the bundled ZSM-48 molecular sieve according to any one of claims 1-7 in the hydroisomerization reaction of hydrocarbon oils.

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