ZSM-5-SBA-15 Composite Molecular Sieve and Its Preparation Method, Hydrorefining Catalyst and Its Application

Abstract

The present invention provides a ZSM-5-SBA-15 composite molecular sieve, a preparation method thereof, a hydrofining catalyst thereof and an application thereof. The preparation method includes mixing an aluminum source, an alkali, water, a first silicon source and a first template agent, and successively performing first aging and first crystallization to obtain a ZSM-5 molecular sieve precursor emulsion; mixing a second template agent, an acid and water, then successively adding the above emulsion and a second silicon source to obtain solution B, successively performing second aging and second crystallization, and performing post-treatment to obtain a ZSM-5-SBA-15 composite molecular sieve. The present invention also provides a ZSM-5-SBA-15 composite molecular sieve obtained by the above preparation method, a hydrofining catalyst containing the composite molecular sieve, and an application of the hydrofining catalyst in the hydrotreating reaction of waste lubricating oil. The above hydrofining catalyst has excellent pore structure, suitable acidity and highly dispersed active metals, and can be applied to the hydro-upgrading and regeneration of waste lubricating oil.

Description

Technical Field

[0001] The present invention relates to the technical field of catalyst manufacturing, and in particular to a ZSM-5-SBA-15 composite molecular sieve and a preparation method thereof, a hydrofining catalyst and an application thereof. Background Art

[0002] Petroleum is a non-renewable natural resource, and the shortage of petroleum resources has become increasingly prominent. In the waste lubricating oil regeneration process, the hydrofining process has the advantages of no waste clay pollution, high oil product yield, convenient operation, simple process, etc. Due to its irreplaceable advantages such as pollution-free, it has gradually become the mainstream technology for waste lubricating oil regeneration. Common hydroprocessing technologies include the Snamprogetti process, the KTI process, and the demetallization-hydrofining process of Phillips Petroleum Company.

[0003] In order to improve the quality of lubricating base oil, technicians have conducted a large number of studies on the hydrofining process and catalysts of lubricating base oil. To produce high-quality lubricating base oil, the key technology is the catalyst, especially the selectivity and stability of the catalyst. In the use of the catalyst, it is generally required that the catalyst has high selectivity and good stability. Therefore, the development of highly active and highly stable deep hydrofining catalysts has become the core and the most important means to solve the problem.

[0004] At present, activated alumina is used as the catalyst carrier. One or more of cobalt, molybdenum, nickel, and tungsten are used as active components. After decades of development, the active components of waste lubricating oil hydrofining catalysts have been relatively mature, and the development of new carriers has become the main direction of the research and development of hydrofining catalysts. In the hydrodesulfurization and denitrification reactions, the most difficult sulfur-containing compounds to remove are dibenzothiophene substances with extremely strong steric hindrance effects and pyridine and quinoline. This not only requires the catalyst to have an open pore structure to eliminate its diffusion effect, but also requires it to have an appropriate acid distribution to enhance the cleavage of C-S and C-N bonds.

[0005] In the prior art, a method of grading a hydro-upgrading catalyst and a hydrodewaxing catalyst can be used to produce a waste lubricating oil hydrogenation catalyst. However, the grading method increases the difficulty of process implementation, and the mechanical mixing method cannot give full play to the advantage of the molecular sieve in adjusting acidity.

[0006] In addition, the prior art also uses a composite molecular sieve containing two phases of microporous molecular sieve and mesoporous molecular sieve to load active components as a hydrogenation catalyst. However, the microporous molecular sieve in the carrier is poorly dispersed and cannot give full play to the synergistic effect of the microporous and mesoporous channels and acidity.

[0007] Therefore, the development of a carrier with an open pore structure and appropriate acid properties has become the key problem in the development of high-performance waste lubricating oil hydrofining catalysts. Summary of the Invention

[0008] In order to solve the above problems, the object of the present invention is to provide a ZSM-5-SBA-15 composite molecular sieve, a preparation method thereof, a hydrofining catalyst and an application thereof. The catalyst has excellent pore structure (high specific surface area, large pore diameter), suitable acidity and highly dispersed active metal, and can be applied to the hydro-upgrading of waste lubricating oil for hydrogenation regeneration of waste lubricating oil.

[0009] To achieve the above object, the present invention provides a preparation method of a ZSM-5-SBA-15 composite molecular sieve, the preparation method comprising: Step 1: uniformly mixing an aluminum source, an alkali, water, a first silicon source and a first template agent, and successively performing first aging and first crystallization to obtain a ZSM-5 molecular sieve precursor emulsion; Step 2: mixing a second template agent, an acid and water to obtain Solution A; mixing Solution A with the ZSM-5 molecular sieve precursor emulsion, and continuing to add a second silicon source, and uniformly mixing to obtain Solution B; successively performing second aging and second crystallization on Solution B, and performing post-treatment to obtain the ZSM-5-SBA-15 composite molecular sieve; wherein, the temperature of the first crystallization is 100-200 °C, the time of the first crystallization is 18-40 h; the temperature of the second crystallization is 80-140 °C, the time of the second crystallization is 18-30 h; the molar ratio of the first silicon source to the second silicon source is 1.6:1 to 1.8:1.

[0010] In the present invention, the ZSM-5 molecular sieve precursor emulsion has ZSM-5 crystal grains with a certain degree of crystallinity. Therefore, this system presents an emulsion form and can be called a microcrystalline emulsion. Adding a second silicon source to the mixed solution of the second template agent, the acid, the water and the ZSM-5 molecular sieve precursor emulsion can cause the second silicon source to undergo hydrolysis and polycondensation with the ZSM-5 crystal grains as nuclei, and after the second crystallization, a composite molecular sieve with an SBA-15 molecular sieve topological structure formed with the ZSM-5 crystal grains as basic units is formed. The composite molecular sieve retains the mesoporous channels of the traditional SBA-15 molecular sieve and at the same time has the micropores of the ZSM-5 molecular sieve, thus presenting a hierarchical pore structure. Moreover, replacing amorphous silica with ZSM-5 crystal grains as the basic unit of the SBA-15 molecular sieve topological structure can increase the mechanical strength of the composite molecular sieve, improve the order degree of the pore structure, and the introduced ZSM-5 molecular sieve can also adjust the acidity of the composite molecular sieve. The micropores in the ZSM-5 molecular sieve can be used as the loading sites of the active metal components, improving the loading amount of the active metal components and the orderliness of the loading positions, and further improving the catalytic activity of the catalyst prepared with the composite molecular sieve as the carrier.

[0011] According to a specific embodiment of the present invention, by controlling the ratio of the first silicon source to the second silicon source, the content of ZSM-5 crystal grains in the composite molecular sieve can be controlled, the order degree of the SBA-15 topological structure can be improved, and further the catalytic activity of the catalyst prepared with the composite molecular sieve as the carrier can be enhanced. In a specific embodiment, the molar ratio of the first silicon source to the second silicon source is generally controlled to be 1.6:l to 1.8:1, and for example, it can be 1.6:1, 1.65:1, 1.7:1, 1.75:1, 1.8:1, etc.

[0012] According to a specific embodiment of the present invention, in the process of preparing the ZSM-5 molecular sieve precursor emulsion, by controlling the ratio of the first silicon source to the aluminum source, the acidity of the composite molecular sieve can be regulated, the loading amount of the active metal component can be increased, and further the catalytic activity of the catalyst prepared with the composite molecular sieve as the carrier can be enhanced. Calculated by the number of moles of SiO2 and Al2O3, the molar ratio of the first silicon source to the aluminum source is generally 4:1 to 35:1, further controllable to 10:1 to 35:1, and still further controllable to 20:1 to 35:1.

[0013] According to a specific embodiment of the present invention, in the process of preparing the ZSM-5 molecular sieve precursor emulsion, calculated by the number of moles of SiO2, the molar ratio of the first silicon source to the first template agent is generally 4-10:1, further can be 5-8:1, and for example, it can be 4:1, 5:1, 6:1, 7:1, 8:1, 9:1, 10:1, etc.

[0014] According to a specific embodiment of the present invention, in the process of preparing the ZSM-5 molecular sieve precursor emulsion (in step 1), calculated by the number of moles of SiO2, the molar ratio of the first silicon source, the base, and water (the water mixed with the base source and the base) is generally 3-8:1:50-100, that is, the molar ratio of the first silicon source to the base is 3-8:1, and for example, it can be 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, etc.; the molar ratio of the base to water is 1:50-100, and for example, it can be 1:50, 1:60, 1:70, l:80, 1:90, 1:100, etc.

[0015] According to a specific embodiment of the present invention, in the process of preparing the ZSM-5 molecular sieve precursor emulsion, the aluminum source includes aluminum sulfate and / or sodium metaaluminate.

[0016] According to a specific embodiment of the present invention, in the process of preparing the ZSM-5 molecular sieve precursor emulsion, the first silicon source includes one or more combinations of silicon dioxide, sodium silicate, and TEOS (tetraethyl orthosilicate). Specifically, the silicon dioxide can also be added in the form of silica sol (a dispersion of nano-silicon dioxide). In some specific embodiments, the first silicon source can include basic silica sol and / or TEOS.

[0017] According to a specific embodiment of the present invention, in the process of preparing the ZSM-5 molecular sieve precursor emulsion, the first template agent includes TPABr (tetrapropylammonium bromide) and / or TPAOH (tetrapropylammonium hydroxide).

[0018] According to a specific embodiment of the present invention, in the process of preparing the ZSM-5 molecular sieve precursor emulsion, the base includes one or a combination of two or more of NaOH, KOH, and ammonia water.

[0019] According to a specific embodiment of the present invention, in the process of preparing the ZSM-5 molecular sieve precursor emulsion, the first template agent, the base, and water can be first mixed under a water bath condition, then the first silicon source and aluminum source are continuously added, and then the first aging and first crystallization are carried out to obtain the ZSM-5 molecular sieve precursor emulsion. In some specific embodiments, the temperature of the water bath can be controlled at 20-50°C. The first silicon source and aluminum source can be added in a dropwise manner.

[0020] According to a specific embodiment of the present invention, in the process of preparing the ZSM-5 molecular sieve precursor emulsion, the temperature of the first aging can be controlled at 30-60°C, further controlled at 50-60°C, and the time of the first aging can be controlled at 2-4 h.

[0021] According to a specific embodiment of the present invention, in the process of preparing the ZSM-5 molecular sieve precursor emulsion, by controlling the conditions of the first crystallization, the crystallization degree of the ZSM-5 molecular sieve can be controlled. The present invention studies and finds that in the ZSM-5 molecular sieve precursor emulsion, if the crystallization degree of the ZSM-5 molecular sieve is too low, the SBA-15 molecular sieve topological structure with ZSM-5 crystal grains as the basic unit cannot be formed; if the crystallization degree of the ZSM-5 molecular sieve is too high, the obtained composite molecular sieve is a phase-separated ZSM-5 molecular sieve and SBA-15 molecular sieve. By controlling the temperature of the first crystallization at 100-200°C and the time at 18-40 h, a composite molecular sieve with the SBA-15 molecular sieve topological structure having ZSM-5 crystal grains as the basic unit can be obtained, thereby improving the catalytic activity of the catalyst prepared with the composite molecular sieve as the carrier.

[0022] Furthermore, the temperature of the first crystallization can be controlled at 150-180°C, and the time of the first crystallization can be controlled at 18-34 h. Further still, the temperature of the first crystallization can be controlled at 160-180°C, and the time of the first crystallization can be controlled at 28-32 h. In a specific embodiment, the temperature of the first crystallization is 170°C, and the time of the first crystallization is 30 h.

[0023] According to a specific embodiment of the present invention, in the process of preparing Solution B, based on the molar amount of SiO2, the molar ratio of the second silicon source to the second templating agent is 50:1 to 80:1.

[0024] According to a specific embodiment of the present invention, in the process of preparing Solution B, the pH value of Solution A is generally controlled to be 0 - 7 to control the hydrolysis rates of the aluminum source, the first silicon source, and the second silicon source.

[0025] According to a specific embodiment of the present invention, in the process of preparing Solution B, the acid includes one or a combination of two or more of HCl, HNO3, HBr, and HI.

[0026] According to a specific embodiment of the present invention, in the process of preparing Solution B, based on the molar amount of SiO2, the molar ratio of the second silicon source, the acid, and water (the water mixed with the second templating agent and the acid) is 1:0.3 - 0.8:16 - 30. That is, the molar ratio of the second silicon source to the acid can be 1:0.3, 1:0.4, 1:0.5, 1:0.6, 1:0.7, 1:0.8; the molar ratio of the second silicon source to water can be 1:16, 1:17, 1:18, 1:19, 1:20, 1:25, 1:27, 1:28, 1:29, 1:30, etc.

[0027] According to a specific embodiment of the present invention, in the process of preparing Solution B, the second silicon source includes TEOS and / or sodium silicate.

[0028] According to a specific embodiment of the present invention, in the process of preparing Solution B, the second templating agent can include one or a combination of two or more of P123, P104, P85, and P65. The above P123, P104, P85, and P65 are poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) triblock copolymers with different degrees of polymerization.

[0029] According to a specific embodiment of the present invention, in the process of preparing Solution A, the temperature of the mixture of the second templating agent, the acid, and water is 20 - 50 °C, for example, 40 °C, and the mixing time can be 20 h. This mixing process can be carried out under water bath conditions.

[0030] According to a specific embodiment of the present invention, the temperature of the second aging is 40 - 90 °C, and the time of the second aging is 18 - 24 h.

[0031] According to the specific embodiments of the present invention, it is found in the research of the present invention that by controlling the conditions of the second crystallization, the hydrothermal stability of the composite molecular sieve can be improved, the structural regrowth of the SBA-15 molecular sieve can be promoted, the structural order degree of the topological structure of the composite molecular sieve can be improved, and further the catalytic activity of the catalyst prepared with the composite molecular sieve as the carrier can be improved. The temperature of the second crystallization is usually controlled at 80-140 °C, and the time is usually controlled at 18-30 h. Further, the temperature of the second crystallization can be controlled at 90-100 °C, and the time of the second crystallization can be controlled at 18-24 h. Still further, the temperature of the second crystallization can be controlled at 95 °C, and the time of the second crystallization is 20 h.

[0032] According to the specific embodiments of the present invention, in the process of preparing the ZSM-5-SBA-15 composite molecular sieve, the post-treatment includes operations of filtering, washing, drying, and calcining the product of the second crystallization. The conditions of drying and calcining can adopt the conventional conditions in the art. For example, the temperature of drying can be 50 °C, the time of drying can be 12-48 h, the temperature of calcining can be 450-650 °C, such as 450 °C, 500 °C, 550 °C, 600 °C, 650 °C, etc., and the time of calcining can be 3-9 h, such as 3 h, 4 h, 5 h, 6 h, 7 h, 8 h, 9 h, etc.

[0033] According to the specific embodiments of the present invention, in the ZSM-5 molecular sieve precursor emulsion and solution A, the water can include at least one of pure water, distilled water, and deionized water, and deionized water is usually adopted.

[0034] According to the specific embodiments of the present invention, in terms of molar parts, the raw materials for preparing the ZSM-5-SBA-15 composite molecular sieve can include: 1 part of the first silicon source (calculated as silicon dioxide), 0.6 part of the second silicon source (calculated as silicon dioxide), 0.092 part of the aluminum source, 0.15 part of the first template agent, 0.01 part of the second template agent, 0.166 part of the base, 15.02 parts of water added during the preparation of the ZSM-5 molecular sieve precursor emulsion, 0.3 part of the acid, and 16.67 parts of water mixed with the second template agent and the acid.

[0035] According to the specific embodiments of the present invention, the preparation method of the ZSM-5-SBA-15 composite molecular sieve specifically can include:

[0036] 1. Mix the first template agent, the base, and water evenly, then continue to add the first silicon source and the aluminum source to obtain a mixed solution, and perform the first aging and the first crystallization on the mixed solution in sequence to obtain a ZSM-5 molecular sieve precursor emulsion;

[0037] Among them, the mass ratio of the first silicon source to the first template agent is 4 - 10:1, the molar ratio of the first silicon source to the aluminum source is 4:1 to 35:1 (calculated based on the molar amounts of SiO2 and Al2O3), the molar ratio of the first silicon source, alkali, and water is 3 - 8:1:50 - 100, the condition for the first aging is aging at 30 - 60°C for 2 - 4 h, and the condition for the first crystallization is crystallization at 100 - 200°C for 18 - 40 h;

[0038] 2. Mix the second template agent, acid, and water to obtain solution A with a pH value of 0 - 7; mix solution A with the ZSM-5 molecular sieve precursor emulsion, and then continue to add the second silicon source and mix evenly to obtain solution B;

[0039] Among them, based on the molar amount of SiO2, the molar ratio of the first silicon source to the second silicon source is 1.6:1 to 1.8:1, the molar ratio of the second silicon source to the second template agent is 50:1 to 80:1, and the molar ratio of the second silicon source, acid, and water is 1:0.3 - 0.8:16 - 30;

[0040] 3. Subject solution B to second aging and second crystallization in sequence, filter, wash, dry, and calcine the second crystallization product to obtain the ZSM-5-SBA-15 composite molecular sieve;

[0041] Among them, the condition for the second aging is aging at 40 - 90°C for 18 - 24 h, and the condition for the second crystallization is crystallization at 80 - 140°C for 18 - 30 h.

[0042] According to a specific implementation manner of the present invention, the preparation method of the ZSM-5-SBA-15 composite molecular sieve may further include:

[0043] 1. Mix 0.5 g of NaAlO2, 0.143 g of NaOH, and 10.0 g of water, stir at 25°C for 1 h to obtain an alkali solution of the aluminum source; after mixing colloidal silica, 8.0 g of H2O, 0.3 g of NaOH, and 2.65 g of TPABr, stir at 25°C until dissolved to obtain an alkali solution of the first silicon source;

[0044] Dropwise add all of the alkali solution of the aluminum source into all of the alkali solution of the first silicon source, stir at 25°C for 3 h, and perform the first aging at 30 - 60°C for 2 - 4 h; load the aged product into a sealed crystallization kettle and perform the first crystallization at 150 - 180°C for 18 - 34 h to synthesize a ZSM-5 molecular sieve microcrystal emulsion;

[0045] 2. Add 4.0 g of P123, 120 mL of H2O, and 20 mL of HCl solution (concentration: 2 mol / L), heat and stir at 40 °C for 2 h to obtain the acidic solution of the second template agent. Dropwise add all of the ZSM-5 molecular sieve microcrystal emulsion into all of the acidic solution of the second template agent, stir at 40 °C for 1 h, then slowly add 8.5 g of TEOS, keep warm and continue stirring for 18 - 24 h to obtain solution B;

[0046] 3. Carry out the second aging of solution B at 40 - 90 °C for 18 - 24 h; seal the aging product in a crystallization kettle, carry out the second crystallization at 80 - 140 °C for 18 - 30 h, and after the crystallization is complete, dry and calcine the crystallization product to obtain the ZSM-5-SBA-15 composite molecular sieve material.

[0047] The present invention also provides a ZSM-5-SBA-15 composite molecular sieve obtained by the above preparation method.

[0048] According to the specific implementation scheme of the present invention, the specific surface area of the ZSM-5-SBA-15 composite molecular sieve is 500 - 1000 m 2 ·g -1 , for example, 500 m 2 ·g -1 , 600 m 2 ·g -1 , 700 m 2 ·g -1 , 800 m 2 ·g -1 , 900 m 2 ·g -1 , 1000 m 2 ·g -1 .

[0049] According to the specific implementation scheme of the present invention, the average pore diameter of the ZSM-5-SBA-15 composite molecular sieve is 3 - 12 nm, further 4 - 10 nm, for example, 3 nm, 4 nm, 5 nm, 6 nm, 7 nm, 8 nm, 9 nm, 10 nm, 11 nm, 12 nm.

[0050] According to the specific implementation scheme of the present invention, the pore volume of the ZSM-5-SBA-15 composite molecular sieve is 0.3 - 1.2 cm 3 ·g -1 , further 1 - 1.2 cm 3 ·g -1 , for example, 0.3 cm 3 ·g -1 , 0.4 cm 3 ·g -1 , 0.5 cm 3 ·g-1 、 0.6 cm 3 · g -1 、 0.7 cm 3 · g -1 、 0.8 cm 3 · g -1 、 0.9 cm 3 · g -1 、 1.1 cm 3 · g -1 、 1.2 cm 3 · g -1 etc.

[0051] The present invention also provides a hydrofining catalyst, which comprises a carrier and an active metal component, and the carrier comprises the above ZSM-5-SBA-15 composite molecular sieve.

[0052] According to a specific embodiment of the present invention, based on metal oxides, the mass content of the active metal component in the hydrofining catalyst is 15-20%, for example, 15%, 16%, 17%, 18%, 19%, 20%.

[0053] In the above hydrofining catalyst, the active metal component is supported on the carrier.

[0054] In the above hydrofining catalyst, the metal elements in the active metal component include Group VIII elements and / or Group VIB elements. Further, the Group VIII elements include Ni, and the Group VIB elements include Mo and / or W.

[0055] In the above hydrofining catalyst, the active metal component comprises a main active metal component and a co-active metal component. The metal elements of the main active metal component are selected from Group VIB, such as Mo and / or W; the metal elements of the co-active metal component are selected from Group VIII, such as Ni, etc.

[0056] In the above hydrofining catalyst, based on metal oxides, the mass content of the main active metal component in the hydrofining catalyst is 10-20%, for example, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, etc. The mass content of the co-active metal component in the hydrofining catalyst is 3%-5%, for example, 3%, 3.5%, 4%, 4.5%, 5%, etc.

[0057] The present invention also provides a method for preparing the above hydrofining catalyst, which includes: performing ammonium exchange treatment on the ZSM-5-SBA-15 composite molecular sieve, impregnating the ammonium-exchanged ZSM-5-SBA-15 composite molecular sieve in a solution of the precursor of the active metal component, drying, and calcining to obtain the hydrofining catalyst.

[0058] In the method for preparing the above hydrofining catalyst, the process of the ammonium exchange treatment may include: mixing the ZSM-5-SBA-15 composite molecular sieve, ammonium salt and water, filtering, washing, drying, and calcining.

[0059] In the above ammonium exchange treatment process, the mass ratio of the ammonium salt to the ZSM-5-SBA-15 composite molecular sieve may be 3-15:1. The ammonium salt can be a soluble ammonium salt, such as ammonium chloride, etc.

[0060] In the above ammonium exchange treatment process, the conditions of drying and calcining can adopt the conventional drying and calcining conditions in the art. For example, the drying temperature can be 100°C and the drying time can be 8h; the calcining temperature can be 450-650°C (such as 450°C, 500°C, 550°C, 600°C, 650°C), and the calcining time can be 3-9h.

[0061] In some embodiments, the above ammonium exchange treatment can be repeated 2-3 times to obtain the ammonium-exchanged ZSM-5-SBA-15 composite molecular sieve.

[0062] In the method for preparing the above hydrofining catalyst, the precursor of the active metal component may include a metal salt of one or a combination of two or more of the following elements: Group VIII elements and / or Group VIB elements. Further, the precursor of the active metal component may include one or a combination of two or more of nickel salt, molybdenum salt, and tungsten salt. Among them, the nickel salt can be a divalent nickel salt, such as including nickel nitrate and / or nickel hypophosphite, the molybdenum salt can be a hexavalent molybdenum salt, such as including ammonium molybdate tetrahydrate, and the tungsten salt can be a hexavalent tungsten salt, such as including ammonium metatungstate.

[0063] The present invention also provides a waste lubricating oil hydrofining catalyst, which includes the above hydrofining catalyst.

[0064] The present invention also provides the application of the above hydrofining catalyst in the hydrotreating reaction of waste lubricating oil. In this hydrotreating reaction, the waste lubricating oil can be upgraded to regenerated base oil. The waste lubricating oil can be various lubricating oil distillates obtained by pretreatment, such as recycled oil. The sulfur content of the waste lubricating oil is usually less than or equal to 2500 μg / g, and the aromatic content is less than or equal to 2000 μg / g. The sulfur content of the regenerated base oil obtained by the hydrotreating reaction can reach below 50 μg / g, and the unsaturated hydrocarbon content can reach below 10%. The viscosity index of the regenerated base oil is not lower than the requirements of the high-viscosity-index hydrotreated type II base oil in "General Lubricating Oil Base Oil" (Q / SY 44-2009).

[0065] In a specific embodiment of the present invention, the hydrofining catalyst has high catalytic activity and can carry out the hydrotreating reaction on waste lubricating oil under mild conditions to obtain a high desulfurization rate and denitrification rate. In some specific embodiments, the hydrofining catalyst can catalyze the hydrotreating reaction of waste lubricating oil under the conditions of a pressure of 4-10 MPa, a temperature of 300-360 °C, a space velocity of 1-1.5 h -1 -1, and a hydrogen-oil ratio of 400-1000:1 to obtain regenerated base oil, and this hydrotreating reaction has a desulfurization rate of more than 97% and a denitrification rate of more than 85%.

[0066] The beneficial effects of the present invention include:

[0067] The synthesis raw materials of the ZSM-5-SBA-15 composite molecular sieve provided by the present invention can be regulated, and it has excellent structural properties. The specific surface area is 500-1000 m 2 ·g -1 -1, the pore diameter is 4-10 nm, the pore volume is 0.3-1.2 cm 3 ·g -1 -1. The pore channels are wide and the pore size distribution is reasonable, and the specific surface area is large, which is beneficial to the highly dispersed active metal and the elimination of the diffusion resistance of reactants and products. Moreover, the acidity of the ZSM-5-SBA-15 composite molecular sieve support is easy to modulate, and the acidity can be modulated to obtain more suitable reaction activity for the problem of complex waste lubricating oil raw material sources.

[0068] Although the catalyst provided by the present invention uses low-cost active metals, it has excellent hydrotreating reaction activity for waste lubricating oil. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] Figure 1 It is the small-angle XRD pattern of the ZSM-5-SBA-15 composite molecular sieve with different silicon-aluminum ratios prepared in Example 1.

[0070] Figure 2 It is the wide-angle XRD pattern of the ZSM-5-SBA-15 composite molecular sieve with different silicon-aluminum ratios prepared in Example 1.

[0071] Figure 3 The N2-adsorption and desorption isotherms of ZSM-5-SBA-15 composite molecular sieves with different silica-alumina ratios were prepared for Example 1.

[0072] Figure 4a The Py-FTIR spectra of ZSM-5-SBA-15 composite molecular sieves with different silica-alumina ratios prepared for Example 1 measured at 200 °C Figure 4b The Py-FTIR spectra of ZSM-5-SBA-15 composite molecular sieves with different silica-alumina ratios prepared for Example 1 measured at 350 °C.

[0073] Figures 5a to 5e The transmission electron microscopy (TEM) images of the hydrofining catalysts made of ZSM-5-SBA-15 composite molecular sieves with different silica-alumina ratios in Example 1.

[0074] Figures 6a to 6e The transmission electron microscopy (TEM) images of the hydrofining catalysts made of ZSM-5-SBA-15 composite molecular sieves with different silica-alumina ratios in Example 1. Detailed implementation manners

[0075] For a clearer understanding of the technical features, objectives, and beneficial effects of the present invention, the technical solutions of the present invention are described in detail below, but it should not be construed as a limitation on the implementable scope of the present invention.

[0076] Example 1

[0077] This example provides a ZSM-5-SBA-15 composite molecular sieve, and its preparation method includes:

[0078] 1. Mix 0.3 g of NaOH, 2.65 g of TPABr, and 8.0 g of H2O, stir until dissolved, add 10.0 g of silica sol (40 wt% SiO2), and stir at room temperature for 1.0 h to obtain a first solution;

[0079] Take 0.143 g of NaOH and a certain mass of NaAlO2, add them to 10 g of H2O, dissolve at room temperature, and stir for 1 h until transparent to obtain a second solution;

[0080] Mix all the first solution and all the second solution, and stir for 2 - 4 h until the formed sol no longer separates into layers to obtain a third solution;

[0081] Age the third solution at 40 °C for the first time for 3 h; transfer the aged third solution to a crystallization kettle, crystallize at 170 °C for 30 h, and the pressure in the crystallization kettle is about 0.4 - 0.5 MPa. After crystallization is completed, the microcrystalline emulsion of ZSM-5 molecular sieve is obtained and reserved.

[0082] 2. At 35 °C, 4.0 g of P123 and 20 ml of 2 mol / L HCl solution were added to 120 ml of H2O, stirred and dissolved to obtain solution A;

[0083] While keeping solution A under rapid stirring, 9.6 g of ZSM-5 molecular sieve microcrystalline emulsion was slowly added to all of solution A, stirred for 1 h, and then 8.5 g of TEOS was slowly added dropwise, and stirring was continued for 20 h to obtain a sol-state solution B;

[0084] 3. Solution B was second-aged at 40 °C for 20 h; the aged solution B was transferred to a crystallization kettle and crystallized at 95 °C for 20 h; then the crystallization product was filtered, washed, dried at 50 °C for 12 h, calcined at 550 °C for 6 h, cooled down to obtain the ZSM-5-SBA-15 composite molecular sieve.

[0085] In step 1, the added masses of NaAlO2 were 1.51 g, 0.7548 g, 0.5 g, 0.302 g, and 0.1888 g respectively, and the molar ratios to SiO2 in the silica sol were 33:1, 16.5:1, 10.9:1, 6.6:1, and 4.1:1 respectively.

[0086] Correspondingly, the composite molecular sieve with 1.51 g of added NaAlO2 was denoted as ZS-15-50 and sample a, the composite molecular sieve with 0.7548 g of added NaAlO2 was denoted as ZS-15-80 and sample b, the composite molecular sieve with 0.5 g of added NaAlO2 was denoted as ZS-15-100 and sample c, the composite molecular sieve with 0.302 g of added NaAlO2 was denoted as ZS-15-120 and sample d, and the composite molecular sieve with 0.1888 g of added NaAlO2 was denoted as ZS-15-150 and sample e.

[0087] The 5 ZSM-5-SBA-15 composite molecular sieves obtained in this example were tested and analyzed. The small-angle XRD and wide-angle XRD results of each sample are as Figure 1 、 Figure 2 shown. The N2-adsorption and desorption isotherms of each sample are as Figure 3 shown; the Py-FTIR spectra of each sample measured at 200 °C are as Figure 4a shown, and the Py-FTIR spectra of each sample measured at 350 °C are as Figure 4b shown.

[0088] From Figures 1 to 4bIt can be seen that: 1. The ZSM-5-SBA-15 composite zeolites with different silica-alumina ratios synthesized by small-angle XRD all have the typical pore structure of SBA-15 and maintain their order after compounding; 2. Wide-angle XRD shows that the ZSM-5-SBA-15 composite zeolite has some primary structural units of ZSM-5, but they do not agglomerate to form a separate phase, but exist in the ZSM-5-SBA-15 composite zeolite in the form of a framework; 3. It can be seen from the N2-adsorption and desorption curves that the composite material has mesoporous and microporous structures; 4. The Py-FTIR spectrum shows that compared with the pure silica-based SBA-15 zeolite, the ZSM-5-SBA-15 composite zeolite has more Bronsted acid and Lewis acid sites, which is beneficial to the activity of the hydrogenation reaction.

[0089] Example 2

[0090] This example provides a hydrofining catalyst, and its preparation method includes:

[0091] 1. The ZSM-5-SBA-15 composite molecular sieve support prepared in Example 1 (sample c, the added mass of sodium aluminate is 0.5 g) and 1 mol / L NH4Cl solution are stirred for 2 h under the condition of an 80°C water bath according to the ratio of 1 g support corresponding to 10 mL NH4Cl solution for ammonium exchange. After filtration, washing, and drying, one ammonium exchange process is completed; then the second ammonium exchange process is carried out in the same steps to obtain an H-type ZSM-5-SBA-15 composite molecular sieve support.

[0092] 2. 0.71 g of ammonium molybdate is dissolved in deionized water to form a solution. This solution is used to impregnate 5 g of the ZSM-5-SBA-15 composite molecular sieve support obtained in step 1. At the same time, ultrasonic dispersion is carried out for 15 min, stirring is carried out for 3 minutes, drying is carried out at 100°C for 5 h, and after calcination at 550°C for 6 h, it is cooled to room temperature to obtain a Mo / ZSM-5-SBA-15 support loaded with molybdenum;

[0093] 3. 0.79 g of nickel nitrate is dissolved in deionized water to form a solution. This solution is used to impregnate the above Mo / ZSM-5-SBA-15 support. At the same time, ultrasonic dispersion is carried out for 15 min, stirring is carried out for 3 min, drying is carried out at 100°C for 5 h, and after calcination at 550°C for 6 h, it is cooled to room temperature to obtain a hydro-upgrading catalyst loaded with molybdenum and nickel, denoted as Cat-ZS.

[0094] After testing, in the above catalyst, Mo is calculated as MoO3, and the mass fraction is 15%; Ni is calculated as NiO, and the mass fraction is 3.5%.

[0095] The 5 types of ZSM-5-SBA-15 composite molecular sieves prepared in Example 1 were made into hydrofining catalysts according to the method of Example 2, and the hydrofining catalysts were sulfided to obtain samples to be tested. The transmission electron microscopy (TEM) results of each catalyst sample to be tested are as Figures 5a to 5e and Figures 6a to 6e shown, where Figure 5a and Figure 6a correspond to the carrier being Sample a of Example 1, Figure 5b and Figure 6b correspond to the carrier being Sample b of Example 1, Figure 5c and Figure 6c correspond to the carrier being Sample c of Example 1, Figure 5d and Figure 6d correspond to the carrier being Sample d of Example 1, Figure 5e and Figure 6e correspond to the carrier being Sample e of Example 1. The conditions of the sulfiding process are: temperature 340 °C, pressure 4 MPa, sulfiding liquid flow rate 2.5 mL / h, for 4 h.

[0096] It can be seen from the TEM transmission electron microscopy results that: the ZSM-5-SBA-15 composite molecular sieve provided by the present invention maintains the original mesoporous channel structure of SBA-15. After introducing ZSM-5 microcrystals into the framework of SBA-15 molecular sieve, the composite material still has relatively regular and uniform pores, indicating that the introduction of ZSM-5 molecular sieve has little effect on the mesoporous channel structure of SBA-15. Moreover, using the ZSM-5-SBA-15 composite molecular sieve as a carrier to prepare a hydrofining catalyst, the active metal components loaded in the catalyst have a relatively high stacking layer number and a high metal dispersion.

[0097] Example 3

[0098] This example provides a hydro-upgrading catalyst, and its preparation process is similar to the Cat-ZS preparation process in Example 2, except that in this example, the type of alkali source in the ZSM-5 molecular sieve microcrystal emulsion is changed to concentrated ammonia water, and the catalyst is denoted as Cat-ZS-A.

[0099] Example 4

[0100] This example provides a hydro-upgrading catalyst, and its preparation process is similar to the Cat-ZS preparation process in Example 2, except that in this example, the alkali source in the ZSM-5 molecular sieve microcrystal emulsion is changed to KOH, and the catalyst is denoted as Cat-ZS-B.

[0101] Example 5

[0102] This example provides a waste lubricating oil hydro-upgrading catalyst with a ZSM-5-SBA-15 composite molecular sieve support. Its preparation process is similar to the Cat-ZS preparation process in Example 2, except that in this example, the type of silicon source in the ZSM-5 molecular sieve microcrystal emulsion is changed to TEOS, and the catalyst is denoted as Cat-ZS-C.

[0103] Example 6

[0104] This example provides a waste lubricating oil hydro-upgrading catalyst with a ZSM-5-SBA-15 composite molecular sieve support. Its preparation process is similar to the Cat-ZS preparation process in Example 2, except that in this example, the acid in Solution A is changed to HNO3, and the catalyst is denoted as Cat-ZS-D.

[0105] Examples 3 to 6 only changed the types of reagents compared to Example 2, and the molar ratios between the reagents remained unchanged.

[0106] Example 7

[0107] This example provides a waste lubricating oil hydro-upgrading catalyst with a ZSM-5-SBA-15 composite molecular sieve support. Its preparation process is similar to the Cat-ZS preparation process in Example 2, except that in this example, the metal elements of the supported active metal components are Ni and W. Calculated by the content of oxides, the mass fraction of the active metal components in the catalyst is: 3.5% NiO, 15% WO, and the catalyst is denoted as Cat-ZS-E.

[0108] Example 8

[0109] This example provides a waste lubricating oil hydro-upgrading catalyst with a ZSM-5-SBA-15 composite molecular sieve support. Its preparation process is similar to the Cat-ZS preparation process in Example 2, except that in this example, the metal elements of the supported active metal components are Ni, Mo, and W. Calculated by the content of oxides, the mass fraction of the active metal components in the catalyst is: 3.5% NiO, 7.5% MoO3, 7.5% WO, and the catalyst is denoted as Cat-ZS-F.

[0110] Example 9

[0111] This example provides a hydro-upgrading catalyst. Its preparation process is similar to the Cat-ZS preparation process in Example 2, except that in this example, the first crystallization condition of the ZSM-5 molecular sieve microcrystal emulsion is changed to crystallization at 110 °C for 20 h, and the catalyst is denoted as Cat-ZS-G.

[0112] Example 10

[0113] This example provides a hydro-upgrading catalyst. Its preparation process is similar to the Cat-ZS preparation process in Example 2, except that in this example, the second crystallization condition of the final composite material is changed to crystallization at 120 °C for 20 h, and the catalyst is denoted as Cat-ZS-H.

[0114] Comparative Example 1

[0115] This comparative example provides a hydrofining catalyst, and its preparation method is as follows:

[0116] Prepare the hydrofining catalyst according to the Cat-ZS method in Example 2. The difference is that in this comparative example, the mechanical mixing method of ZSM-5 and SBA-15 is used as the catalyst support, and the obtained catalyst is denoted as Cat-Z-S.

[0117] Comparative Example 2

[0118] This comparative example provides a hydrofining catalyst, and its preparation method is as follows:

[0119] Prepare the hydrofining catalyst according to the Cat-ZS method in Example 2. The difference is that in this comparative example, the method of Example 3 of CN201110077193.7 (invention name: A production method of p-tert-butyltoluene, publication number: CN102199068A) is used to prepare the catalyst support, and the obtained catalyst is denoted as Cat-ZSA.

[0120] Test Example 1

[0121] This test example provides the characterization test results of the molecular sieve supports in the above examples and comparative examples.

[0122] Perform structural characterization on the ZSM-5-SBA-15 composite molecular sieves in Test Examples 1 to 8 and the molecular sieve supports in Comparative Examples 1 to 2, and the results are summarized in Table 1.

[0123] Table 1

[0124]

[0125] It can be seen from the results in Table 1 that the ZSM-5-SBA-15 composite molecular sieve provided by the present invention has a higher specific surface area and a more developed pore structure than the molecular sieve in the comparative example. Through the comparison results, it can be seen that when the first silicon source is alkaline silica sol, the base is NaOH, the acid is HCl, and the supported active metal components are Ni, Mo, and W, the pore structure of the obtained ZSM-5-SBA-15 composite molecular sieve is relatively ideal. And the composite molecular sieve synthesized by the present invention has both micropores and mesopores at the same time.

[0126] Test Example 2

[0127] This test example provides the structural characterization results of the catalyst prepared from the ZSM-5-SBA-15 composite molecular sieve. The sample to be tested is a hydrofining catalyst prepared by using five ZSM-5-SBA-15 composite molecular sieves with different silica-alumina ratios in Example 1 as carriers and according to the methods and parameters in Example 2.

[0128] Through the test method of Py-FTIR, the acidic site results of each catalyst sample measured at 200 °C and 350 °C are shown in Table 2.

[0129] Table 2

[0130]

[0131] It can be seen from Table 2 that compared with the conventional SBA-15 molecular sieve, the acidic sites of the ZSM-5-SBA-15 composite molecular sieve provided by the present invention are significantly improved, especially the quantity and proportion of B acid are significantly increased.

[0132] Test Example 3

[0133] This test example provides the performance tests of the catalysts in Examples 2 to 8 and Comparative Examples 1 to 2. The properties of the waste lubricating oil raw material are shown in Table 3.

[0134] Table 3

[0135] Item Feedstock oil Viscosity index 149 Color number / D1500 >8 Density / g.cm-3 0.883 Sulfur content / μg.g-1 2020 Nitrogen content / μg.g-1 351 <![CDATA[40℃ kinematic viscosity / mm 2 .s -1 > 68.89 <![CDATA[100℃ kinematic viscosity / mm 2 .s -1 > 10.89

[0136] Using pretreated waste lubricating oil as the feedstock and the above catalyst as the refining agent, the hydrofining reaction conditions were optimized, and the raw material conversion rate, product distribution and yield were investigated.

[0137] The specific test method for the catalyst is as follows:

[0138] 1. Catalyst loading: quartz wool + quartz sand (20-40 mesh) 14 mL + quartz wool + refining agent 2 g + quartz wool + quartz sand 6 mL + quartz wool;

[0139] 2. Conditions during the presulfurization process: temperature 340 °C, pressure 4 MPa, sulfurizing liquid flow rate 2.5 mL / h; stabilizing for 4 h;

[0140] 3. Reaction conditions during the evaluation process: reaction temperature 350 °C, pressure 5 MPa, mass space velocity 1.0 h -1 , hydrogen-oil ratio 600.

[0141] The test results are summarized in Table 4. Among them, the sulfur content is measured according to "GB / T 17040-2008 Determination of sulfur content in petroleum and petroleum products - Energy dispersive X-ray fluorescence spectrometry". The nitrogen content is measured according to "GB / T 9170-1988 Determination of total nitrogen content in lubricating oil and fuel oil (modified Kjeldahl method)". The saturated hydrocarbon content is measured according to "Determination of total aromatic hydrocarbon and total saturated hydrocarbon content in lubricating base oil - High performance liquid chromatography with differential refractive index detector", and the content of unsaturated hydrocarbons can be calculated according to "100% - saturated hydrocarbon content (%)".

[0142] Table 4

[0143] Number Sulfur content, μg / g Nitrogen content, μg / g Saturated hydrocarbons, % Example 2 10 5 98.8 Example 3 27 16 94.5 Example 4 45 22 92.0 Example 5 30 17 93.8 Example 6 26 16 95.8 Example 7 20 9 96.5 Example 8 15 7 96.8 Comparative Example 1 67 30 67 Comparative Example 2 120 58 80

[0144] As can be seen from Table 3, the hydrogenation effects of the catalysts prepared in Examples 2 to 8 on waste lubricating oil are higher than those of Comparative Example 1 and Comparative Example 2. The catalyst in Example 2 has the best hydro-upgrading effect, with a desulfurization rate higher than 97% and a denitrification rate higher than 85%.

[0145] The above results show that the ZSM-5-SBA-15 composite molecular sieve provided by the present invention has wide pores and a reasonable pore size distribution, a large specific surface area, which is conducive to the highly dispersed active metal and eliminates the diffusion resistance of reactants and products. Moreover, the acidity of the ZSM-5-SBA-15 composite molecular sieve support is easy to modulate, and the acidity can be modulated for the problem of complex sources of waste lubricating oil raw materials to obtain more suitable reaction activity. The catalyst obtained by loading a cheap active metal on the composite molecular sieve has excellent hydrogenation reaction activity for waste lubricating oil.

Claims

1. Application of a hydrofining catalyst in the hydrotreating reaction of waste lubricating oil, wherein, The hydrofining catalyst described above comprises a support and an active metal component, and the support comprises a ZSM-5-SBA-15 composite molecular sieve; The preparation method of the ZSM-5-SBA-15 composite molecular sieve comprises: Step 1: Uniformly mix an aluminum source, an alkali, water, a first silicon source, and a first templating agent, and successively carry out a first aging and a first crystallization to obtain a ZSM-5 molecular sieve precursor emulsion; Step 2: Mix a second templating agent, an acid, and water to obtain Solution A; mix Solution A with the ZSM-5 molecular sieve precursor emulsion, continue to add a second silicon source, and uniformly mix to obtain Solution B; subject Solution B to a second aging and a second crystallization, and post-treatment to obtain the ZSM-5-SBA-15 composite molecular sieve; Wherein, the temperature of the first crystallization is 100-200 °C, the time of the first crystallization is 18-40 h; the temperature of the second crystallization is 80-140 °C, the time of the second crystallization is 18-30 h; the molar ratio of the first silicon source to the second silicon source is 1.6:1 to 1.8:1; in Step 1, based on the number of moles of SiO2, the molar ratio of the first silicon source, the alkali, and water is 3-8:1:50-100; In Step 1, based on the number of moles of SiO2 and Al2O3, the molar ratio of the first silicon source to the aluminum source is 4:1 to 35:

1.

2. The application according to claim 1, wherein In Step 1, based on the number of moles of SiO2 and Al2O3, the molar ratio of the first silicon source to the aluminum source is 10:1 to 35:

1.

3. The application according to claim 1, wherein In Step 1, based on the number of moles of SiO2 and Al2O3, the molar ratio of the first silicon source to the aluminum source is 20:1 to 35:

1.

4. The application according to claim 1, wherein, In Step 1, based on the number of moles of SiO2, the molar ratio of the first silicon source to the first templating agent is 4-10:

1.

5. The application according to claim 1, wherein, In Step 1, based on the number of moles of SiO2, the molar ratio of the first silicon source to the first templating agent is 5-8:

1.

6. The application according to claim 1, wherein, In Step 2, based on the number of moles of SiO2, the molar ratio of the second silicon source to the second templating agent is 50:1 to 80:

1.

7. The application according to claim 1, wherein In Step 2, based on the number of moles of SiO2, the molar ratio of the second silicon source, the acid, and water is 1: :16-30.

8. The application according to claim 1, wherein, In Step 2, based on the number of moles of SiO2, the molar ratio of the second silicon source, the acid, and water is 1: :20-30.

9. The application according to claim 1, wherein, The aluminum source comprises aluminum sulfate and / or sodium metaaluminate; and / or, the first silicon source comprises one or a combination of two or more of silicon dioxide, sodium silicate, and TEOS; and / or, the first templating agent comprises TPABr and / or TPAOH; and / or, the second silicon source comprises TEOS and / or sodium silicate; and / or, the second templating agent comprises one or a combination of two or more of P123, P104, P85, and P65.

10. The application according to claim 1, wherein, The temperature of the first crystallization is 150-180 °C, the time of the first crystallization is 18-34 h; and / or, the temperature of the second crystallization is 90-100 °C, the time of the second crystallization is 18-24 h.

11. The application according to claim 1, wherein, The temperature of the first crystallization is 160 - 180 °C, and the time of the first crystallization is 28 - 32 h.

12. The application according to claim 1, wherein The temperature of the first crystallization is 170 °C, and the time of the first crystallization is 30 h.

13. The application according to claim 1, wherein, The temperature of the second crystallization is 95 °C, and the time of the second crystallization is 20 h.

14. The application according to claim 1, wherein The temperature of the first aging is 30 - 60 °C, and the time of the first aging is 2 - 4 h; and / or, the temperature of the second aging is 40 - 90 °C, and the time of the second aging is 18 - 24 h.

15. The application according to claim 1, wherein, The temperature of the first aging is 50 - 60 °C.

16. The application according to claim 1, wherein, The specific surface area of the ZSM-5-SBA-15 composite molecular sieve is 500-1000 m 2 ·g -1 .

17. The application according to claim 1, wherein The average pore diameter of the ZSM-5-SBA-15 composite molecular sieve is 3 - 12 nm.

18. The application according to claim 1, wherein, The average pore diameter of the ZSM-5-SBA-15 composite molecular sieve is 4 - 10 nm.

19. The application according to claim 1, wherein, The pore volume of the ZSM-5-SBA-15 composite molecular sieve is 0.3-1.2 cm 3 ·g -1 .

20. The application according to claim 1, wherein The pore volume of the ZSM-5-SBA-15 composite molecular sieve is 1-1.2 cm 3 ·g -1 .

21. The application according to claim 1, wherein, Calculated as metal oxide, the mass content of the active metal component in the hydrofining catalyst is 15% - 20%.

22. The application according to claim 1 or 21, wherein, The metal elements in the active metal component include Group VIII elements and / or Group VIB elements.

23. The application according to claim 22, wherein, The Group VIII elements include Ni, and the Group VIB elements include Mo and / or W.

24. The application according to claim 1, wherein, The pressure of the hydrogenation reaction is 4 - 10 MPa, the temperature is 300 - 360 °C, the space velocity is 1 - 1.5 h -1 , and the hydrogen-oil ratio is 400 - 1000:1.

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