A full-fraction waste mineral oil hydrogenation catalyst and preparation method

Abstract

The present invention belongs to the field of catalyst technology, and specifically relates to a novel full-fraction waste mineral oil hydrogenation catalyst and a preparation method. The present invention adopts polyethylene glycol as a surfactant, and prepares a high specific surface area catalyst carrier by a coprecipitation process. And on the basis of the Mo-Co catalyst, a certain amount of metallic manganese and cerium are added. The pre-deposited cerium oxide additive promotes the dispersion of active components in the catalyst, weakens the interaction between the metal and the carrier, and promotes the increase of the specific surface area of ​​the catalyst. The addition of manganese can enhance the interaction between the various components of the catalyst, especially the formation of manganese oxide can effectively promote the dispersion of active components, prevent the catalyst from being over-sintered, thereby effectively improving the activity of the catalyst. The catalyst has a high specific surface area and pore size, high catalytic activity, effectively improves the desulfurization and denitrification rates of waste mineral oil, and has broad application prospects.

Description

Technical Field

[0001] The invention belongs to the technical field of catalysts, and in particular relates to a novel full-fraction waste mineral oil hydrogenation catalyst and a preparation method thereof. Background Art

[0002] As oil resources are increasingly depleted and the price of oil products continues to rise, the recycling and reuse of waste mineral oil will achieve higher social application value and ecological benefits in terms of economy, resources and environment. Waste mineral oil has a wide range of sources, is extremely harmful and difficult to handle. Most of the initial waste mineral oil is directly incinerated, discarded, and landfilled. A small part of the waste mineral oil is regenerated and cracked to produce fuel oil, which not only causes serious waste of resources but also causes environmental pollution. Among them, lubricating oil is the most common type of waste mineral oil due to its wide use.

[0003] After a period of use, lubricating oil will deteriorate in performance and quality, whether due to human factors or natural influences, and lose the excellent performance of the original oil. Lubricating oil that can no longer be used due to the above reasons is called "waste oil". During the use of lubricating oil, since the nitrogen oxides, sulfides and fuel contained in the lubricating oil itself cannot be completely burned, insoluble sediments such as colloid, sludge, and metal debris are formed, the viscosity of the lubricating oil increases, the fluidity slows down, the heat dissipation deteriorates, and the color of the oil turns black.

[0004] The gum, sludge, nitrogen and sulfur oxides and other substances generated after the engine oil deteriorates have a great impact on the combustion performance of the diesel engine. The acid value of the lubricating oil will continue to increase and the aging speed will continue to accelerate; gum and carbon deposits cause the heat dissipation of parts to slow down and accelerate the wear between parts; sludge is a mixture of water and engine oil, which is easy to adhere to the pipe wall; it hinders the fluidity of the lubricating oil, increases the resistance of the oil pipe, increases the wear and oxidation rate of the machinery, and reduces the service life of the engine.

[0005] The production of waste mineral oil is increasing year by year. From an environmental perspective, the direct discharge of waste mineral oil not only causes a waste of resources, but also pollutes groundwater and damages the soil. Therefore, it is urgent to develop an effective method to achieve efficient recycling of waste lubricating oil.

[0006] At present, the main processes used for the recycling and treatment of waste lubricating oil include sulfuric acid-kaolin process, flocculation process, distillation-solvent refining process, molecular distillation technology, supercritical extraction technology, membrane separation technology and hydrogenation refining process. Among them, the sulfuric acid-kaolin process is gradually being eliminated because it will produce a large amount of waste acid, solid waste and serious equipment corrosion; the flocculation process is to remove solid particles that are difficult to settle by adding flocculants, but the refining depth often does not meet the requirements; the distillation-solvent refining process requires a large amount of organic solvents, and the energy consumption is large and the product quality is unstable; molecular distillation technology, supercritical extraction technology, and membrane separation technology are new regeneration technologies, which are not mature enough at present. The hydrogenation refining process can not only remove sulfur, oxygen, nitrogen, and chlorine compounds, but also hydrogenate unsaturated organic matter to improve the quality of oil products. Therefore, this method has a wider application prospect. Summary of the invention

[0007] In order to promote the recycling of waste mineral oil, the present invention provides a novel full-fraction waste mineral oil hydrogenation catalyst and a preparation method thereof. The catalyst has a high specific surface area and pore size, high catalytic activity, and effectively improves the desulfurization and denitrification rates of waste mineral oil.

[0008] The present invention is achieved through the following technical solutions:

[0009] A method for preparing a novel full-fraction waste mineral oil hydrogenation catalyst comprises the following steps:

[0010] (1) A modified alumina carrier is prepared by coprecipitation and calcination using aluminum salt, ammonium salt and PEG surfactant as raw materials; wherein the number average molecular weight of PEG is 800-2000;

[0011] (2) impregnating a modified alumina carrier with a cerium-containing solution, drying and calcining to obtain a primary catalyst;

[0012] (3) A primary catalyst is impregnated with a mixed solution containing molybdenum, cobalt and manganese, and after drying and calcination, a full-fraction waste mineral oil hydrogenation catalyst is obtained; wherein, in terms of oxide content, the MoO3 content is 16-20wt%, the CoO content is 5-10wt%, the MnO2 content is 2-4wt%, and the CeO2 content is 0.5-1.2wt%.

[0013] In a supported catalyst, the carrier can provide a large specific surface area to ensure the dispersion of active metals and good activity and selectivity. At present, the commonly used supported hydrogenation catalyst carrier in industry is Al2O3. When alumina is used as a carrier, the active component can maximize its hydrogenation activity. Hydrogenation catalyst carriers are generally required to have a high specific surface area and a suitable pore size. In order to increase the surface area of ​​the alumina carrier and improve its loading capacity, the present invention adopts polyethylene glycol as a surfactant and prepares a high specific surface area catalyst carrier by a co-precipitation process. By selecting polyethylene glycol with a number average molecular weight of 800-2000 as a surfactant, the dispersion of the precipitate can be promoted, which is beneficial to the formation of interstitial pores. When the molecular weight is too small, the dispersing effect is limited; when the molecular weight is too large, it is easy to cause the mechanical strength of the carrier to be low, and structural collapse is prone to occur during high-temperature calcination.

[0014] The metal active components commonly used in hydrogenation catalysts are generally transition metal elements and their compounds. They include molybdenum and tungsten of group VIB and cobalt, nickel, iron, palladium and platinum of group VIII. These metal elements all have unfilled d orbitals. At the same time, they all have body-centered or face-centered cubic lattices or hexagonal lattices, and they all have the conditions to be active components in terms of electronic properties and geometric properties. When molybdenum and cobalt exist alone, the catalytic activity is not high, but when the two exist at the same time, they produce a synergistic effect and show very high catalytic activity. In order to further improve the performance of the catalyst, the present invention adds a certain amount of metal manganese and cerium. The cerium additive can increase the dispersion of the active components on the surface of the carrier and improve the catalytic activity. Metal manganese can change the synergistic effect between different metals and thus change the catalytic selectivity. By pre-depositing cerium salts, the cerium oxide additive significantly promotes the dispersion of active components in the catalyst, weakens the interaction between the metal and the carrier, increases the specific surface area of ​​the catalyst, and thus increases the number of active species on the catalyst surface. When the amount of cerium oxide is too small, the dispersion effect is limited; when the amount of cerium oxide is too large, it will lead to an increase in grain size and a decrease in specific surface area and pore size. This is because the cerium oxide introduced by the impregnation method is loaded onto the surface of the carrier, causing partial pore blockage. Since the transition metal Mn element has a variety of variable d-electron structures, it has a special effect on the hydrogenation reaction: the addition of manganese can enhance the interaction between the components of the catalyst, especially the formation of manganese oxide can effectively promote the dispersion of active components and prevent catalyst sintering, thereby effectively improving the activity of the catalyst. In addition, the addition of manganese oxide reduces the particle size of molybdenum and increases the dispersion of molybdenum.

[0015] Further, in the full-fraction waste mineral oil hydrogenation catalyst, in terms of oxide content, the MoO3 content is 16-20wt%, the CoO content is 6.5-8.5wt%, the MnO2 content is 2.5-3.4wt%, and the CeO2 content is 0.5-1.2wt%. The active metal components in the present invention are loaded onto an alumina carrier by a step-by-step impregnation method, and either isovolumetric impregnation or excessive impregnation can be used. Further, the present invention prepares the catalyst by an isovolumetric impregnation process. The isovolumetric impregnation method can conveniently control the loading amount of the active component by accurately controlling the volume of the solution to be equal to that of the carrier, thereby ensuring that the active component content of the catalyst is accurate. Specifically, metal salts such as ammonium molybdate, cobalt nitrate, manganese nitrate, and cerium nitrate are calcined to generate metal oxides such as MoO3, CoO, MnO2, and CeO2. According to the water absorption rate and mass of the carrier and the primary catalyst, a cerium nitrate solution and a mixed solution containing ammonium molybdate, cobalt nitrate and manganese nitrate with corresponding mass fractions (in terms of oxides) are respectively prepared, and the metal components are completely impregnated into the surface of the carrier or the primary catalyst by the equal volume impregnation method. The corresponding catalyst is prepared directly after drying and calcination. In particular, multiple equal volume impregnation processes can also be used to load the active components onto the catalyst surface.

[0016] Furthermore, in step (1), the aluminum salt is any one of aluminum nitrate and aluminum chloride; and the ammonium salt is any one of ammonium bicarbonate and ammonium chloride.

[0017] Furthermore, the number average molecular weight of PEG in step (1) is 1000-1500. Since the present invention adopts a step-by-step impregnation and calcination process, it is necessary to control the molecular weight of polyethylene glycol to prevent the collapse of the porous structure of alumina during the calcination process.

[0018] Furthermore, in step (1), the molar ratio of ammonium salt to aluminum salt is (6-9):1; and the mass ratio of PEG surfactant to aluminum salt is (0.8-1.2):1.

[0019] Furthermore, the specific preparation process of the modified alumina carrier in step (1) is:

[0020] First, aluminum salt and PEG surfactant were dissolved in deionized water to prepare a mixed solution; the aluminum salt concentration in the mixed solution was 0.2 mol / L;

[0021] Under stirring conditions, the mixed solution is added dropwise to an ammonium salt aqueous solution, and the pH of the ammonium salt aqueous solution is adjusted to 8-9; a precipitate is obtained after aging; before the addition, the ammonium salt concentration in the ammonium salt aqueous solution is 0.7-0.9 mol / L;

[0022] The precipitate is calcined at 580-650°C for 4-6 hours to obtain a modified alumina carrier.

[0023] The co-precipitation method is used to prepare alumina carriers. The materials used are readily available, the preparation process is relatively simple, and it does not require expensive equipment and expertise, making it suitable for large-scale production.

[0024] Furthermore, the cerium-containing solution in step (2) is a cerium nitrate solution.

[0025] Furthermore, in step (2), the drying temperature is 110-120°C; the roasting temperature is 500-550°C, and the roasting time is 3.5-5h.

[0026] Furthermore, the mixed solution containing molybdenum, cobalt and manganese in step (3) is a mixed solution containing ammonium molybdate, cobalt nitrate and manganese nitrate.

[0027] Furthermore, it is characterized in that in step (3), the drying temperature is 105-110°C; the roasting temperature is 500-600°C, and the roasting time is 4-5h.

[0028] On the other hand, the present invention also provides a novel full-fraction waste mineral oil hydrogenation catalyst, which has a high specific surface area and pore size, high catalytic activity, and effectively improves the desulfurization and denitrification rates of the waste mineral oil.

[0029] Beneficial effects: The present invention adopts polyethylene glycol as a surfactant and prepares a catalyst carrier with a high specific surface area through a coprecipitation process. By selecting polyethylene glycol with a number average molecular weight of 800-2000 as a surfactant, the dispersion of the precipitate can be promoted, which is conducive to the formation of interstitial pores. In order to further improve the performance of the Mo-Co catalyst, the present invention adds a certain amount of metallic manganese and cerium. By pre-depositing cerium salt, the cerium oxide additive significantly promotes the dispersion of active components in the catalyst, weakens the interaction between the metal and the carrier, increases the specific surface area of ​​the catalyst, and thus increases the number of active species on the catalyst surface. The addition of manganese can enhance the interaction between the various components of the catalyst, especially the formation of manganese oxide can effectively promote the dispersion of active components and prevent the catalyst from sintering, thereby effectively improving the activity of the catalyst, and the addition of manganese oxide reduces the particle size of molybdenum and increases the dispersion of molybdenum. The catalyst has a high specific surface area and pore size, high catalytic activity, effectively improves the desulfurization and denitrification rates of waste mineral oil, and has broad application prospects. DETAILED DESCRIPTION

[0030] The experimental methods in the following examples of the present invention, where no specific conditions are specified, are usually carried out under conventional conditions or under conditions recommended by the manufacturers. The various commonly used chemical reagents used in the examples are all commercially available products.

[0031] Unless otherwise defined, all technical and scientific terms used in the present invention have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0032] The terms "including" and "having" and any variations thereof of the present invention are intended to cover non-exclusive inclusions. For example, a process, method, device, product or equipment comprising a series of steps is not limited to the listed steps or modules, but may optionally include steps not listed, or may optionally include other steps inherent to these processes, methods, products or equipment.

[0033] Example 1

[0034] A method for preparing a novel full-fraction waste mineral oil hydrogenation catalyst comprises the following steps:

[0035] (1) Firstly, aluminum salt and PEG surfactant are dissolved in deionized water to prepare a mixed solution; under stirring, the mixed solution is added dropwise to an ammonium salt aqueous solution, and the pH of the ammonium salt aqueous solution is adjusted to 8; after aging, a precipitate is obtained; and the precipitate is calcined at 620° C. for 5 h to obtain a modified alumina carrier; wherein the number average molecular weight of PEG is 1000; the aluminum salt is aluminum nitrate; the ammonium salt is ammonium bicarbonate; the molar ratio of the ammonium salt to the aluminum salt is 6:1; and the mass ratio of the PEG surfactant to the aluminum salt is 0.8:1;

[0036] (2) impregnating a modified alumina carrier with a cerium-containing solution, drying and calcining to obtain a primary catalyst; the cerium-containing solution is a cerium nitrate solution; the drying temperature is 115°C; the calcination temperature is 500°C, and the calcination time is 5 hours;

[0037] (3) A primary catalyst is impregnated with a mixed solution containing molybdenum, cobalt and manganese, and after drying and calcination, a full-fraction waste mineral oil hydrogenation catalyst is obtained; wherein, in terms of oxide content, the MoO3 content is 16wt%, the CoO content is 6.5wt%, the MnO2 content is 2.5wt%, and the CeO2 content is 0.5wt%; the mixed solution containing molybdenum, cobalt and manganese is a mixed solution containing ammonium molybdate, cobalt nitrate and manganese nitrate; the drying temperature is 108°C; the calcination temperature is 500°C, and the calcination time is 5h.

[0038] Example 2

[0039] A method for preparing a novel full-fraction waste mineral oil hydrogenation catalyst comprises the following steps:

[0040] (1) Firstly, aluminum salt and PEG surfactant are dissolved in deionized water to prepare a mixed solution; under stirring, the mixed solution is added dropwise to an ammonium salt aqueous solution, and the pH of the ammonium salt aqueous solution is adjusted to 8; after aging, a precipitate is obtained; the precipitate is calcined at 620°C for 5 hours to obtain a modified alumina carrier; wherein the number average molecular weight of PEG is 2000; the aluminum salt is aluminum nitrate; the ammonium salt is ammonium bicarbonate; the molar ratio of the ammonium salt to the aluminum salt is 9:1; and the mass ratio of the PEG surfactant to the aluminum salt is 1.2:1;

[0041] (2) impregnating a modified alumina carrier with a cerium-containing solution, drying and calcining to obtain a primary catalyst; the cerium-containing solution is a cerium nitrate solution; the drying temperature is 115°C; the calcination temperature is 550°C, and the calcination time is 3.5 hours;

[0042] (3) A primary catalyst is impregnated with a mixed solution containing molybdenum, cobalt and manganese, and after drying and calcination, a full-fraction waste mineral oil hydrogenation catalyst is obtained; wherein, in terms of oxide content, the MoO3 content is 20wt%, the CoO content is 8.5wt%, the MnO2 content is 3.4wt%, and the CeO2 content is 1.2wt%; the mixed solution containing molybdenum, cobalt and manganese is a mixed solution containing ammonium molybdate, cobalt nitrate and manganese nitrate; the drying temperature is 108°C; the calcination temperature is 600°C, and the calcination time is 4h.

[0043] Example 3

[0044] A method for preparing a novel full-fraction waste mineral oil hydrogenation catalyst comprises the following steps:

[0045] (1) Firstly, aluminum salt and PEG surfactant are dissolved in deionized water to prepare a mixed solution; under stirring, the mixed solution is added dropwise to an ammonium salt aqueous solution, and the pH of the ammonium salt aqueous solution is adjusted to 8; after aging, a precipitate is obtained; and the precipitate is calcined at 620° C. for 5 h to obtain a modified alumina carrier; wherein the number average molecular weight of PEG is 1000; the aluminum salt is aluminum nitrate; the ammonium salt is ammonium bicarbonate; the molar ratio of the ammonium salt to the aluminum salt is 9:1; and the mass ratio of the PEG surfactant to the aluminum salt is 0.8:1;

[0046] (2) impregnating a modified alumina carrier with a cerium-containing solution, drying and calcining to obtain a primary catalyst; the cerium-containing solution is a cerium nitrate solution; the drying temperature is 115°C; the calcination temperature is 550°C, and the calcination time is 3.5 hours;

[0047] (3) A primary catalyst is impregnated with a mixed solution containing molybdenum, cobalt and manganese, and after drying and calcination, a full-fraction waste mineral oil hydrogenation catalyst is obtained; wherein, in terms of oxide content, the MoO3 content is 20wt%, the CoO content is 6.5wt%, the MnO2 content is 3.4wt%, and the CeO2 content is 0.5wt%; the mixed solution containing molybdenum, cobalt and manganese is a mixed solution containing ammonium molybdate, cobalt nitrate and manganese nitrate; the drying temperature is 108°C; the calcination temperature is 500°C, and the calcination time is 4h.

[0048] Example 4

[0049] A method for preparing a novel full-fraction waste mineral oil hydrogenation catalyst comprises the following steps:

[0050] (1) Firstly, aluminum salt and PEG surfactant are dissolved in deionized water to prepare a mixed solution; under stirring, the mixed solution is added dropwise to an ammonium salt aqueous solution, and the pH of the ammonium salt aqueous solution is adjusted to 8; after aging, a precipitate is obtained; and the precipitate is calcined at 620° C. for 5 h to obtain a modified alumina carrier; wherein the number average molecular weight of PEG is 1200; the aluminum salt is aluminum nitrate; the ammonium salt is ammonium bicarbonate; the molar ratio of the ammonium salt to the aluminum salt is 7:1; and the mass ratio of the PEG surfactant to the aluminum salt is 0.9:1;

[0051] (2) impregnating a modified alumina carrier with a cerium-containing solution, drying and calcining to obtain a primary catalyst; the cerium-containing solution is a cerium nitrate solution; the drying temperature is 115°C; the calcination temperature is 520°C, and the calcination time is 4.5 hours;

[0052] (3) A primary catalyst is impregnated with a mixed solution containing molybdenum, cobalt and manganese, and after drying and calcination, a full-fraction waste mineral oil hydrogenation catalyst is obtained; wherein, in terms of oxide content, the MoO3 content is 17wt%, the CoO content is 7wt%, the MnO2 content is 2.9wt%, and the CeO2 content is 0.7wt%; the mixed solution containing molybdenum, cobalt and manganese is a mixed solution containing ammonium molybdate, cobalt nitrate and manganese nitrate; the drying temperature is 108°C; the calcination temperature is 530°C, and the calcination time is 4.8h.

[0053] Example 5

[0054] A method for preparing a novel full-fraction waste mineral oil hydrogenation catalyst comprises the following steps:

[0055] (1) Firstly, aluminum salt and PEG surfactant are dissolved in deionized water to prepare a mixed solution; under stirring, the mixed solution is added dropwise to an ammonium salt aqueous solution, and the pH of the ammonium salt aqueous solution is adjusted to 8; after aging, a precipitate is obtained; and the precipitate is calcined at 620° C. for 5 h to obtain a modified alumina carrier; wherein the number average molecular weight of PEG is 1800; the aluminum salt is aluminum nitrate; the ammonium salt is ammonium bicarbonate; the molar ratio of the ammonium salt to the aluminum salt is 8:1; and the mass ratio of the PEG surfactant to the aluminum salt is 1.1:1;

[0056] (2) impregnating a modified alumina carrier with a cerium-containing solution, drying and calcining to obtain a primary catalyst; the cerium-containing solution is a cerium nitrate solution; the drying temperature is 115°C; the calcination temperature is 540°C, and the calcination time is 3.9 hours;

[0057] (3) A primary catalyst is impregnated with a mixed solution containing molybdenum, cobalt and manganese, and after drying and calcination, a full-fraction waste mineral oil hydrogenation catalyst is obtained; wherein, in terms of oxide content, the MoO3 content is 19wt%, the CoO content is 8wt%, the MnO2 content is 3.2wt%, and the CeO2 content is 1.1wt%; the mixed solution containing molybdenum, cobalt and manganese is a mixed solution containing ammonium molybdate, cobalt nitrate and manganese nitrate; the drying temperature is 108°C; the calcination temperature is 580°C, and the calcination time is 4.2h.

[0058] Example 6

[0059] A method for preparing a novel full-fraction waste mineral oil hydrogenation catalyst comprises the following steps:

[0060] (1) Firstly, aluminum salt and PEG surfactant are dissolved in deionized water to prepare a mixed solution; under stirring, the mixed solution is added dropwise to an ammonium salt aqueous solution, and the pH of the ammonium salt aqueous solution is adjusted to 8; after aging, a precipitate is obtained; and the precipitate is calcined at 620° C. for 5 h to obtain a modified alumina carrier; wherein the number average molecular weight of PEG is 800; the aluminum salt is aluminum nitrate; the ammonium salt is ammonium bicarbonate; the molar ratio of the ammonium salt to the aluminum salt is 8:1; and the mass ratio of the PEG surfactant to the aluminum salt is 1:1;

[0061] (2) impregnating a modified alumina carrier with a cerium-containing solution, drying and calcining to obtain a primary catalyst; the cerium-containing solution is a cerium nitrate solution; the drying temperature is 115°C; the calcination temperature is 530°C, and the calcination time is 4 hours;

[0062] (3) A primary catalyst is impregnated with a mixed solution containing molybdenum, cobalt and manganese, and after drying and calcination, a full-fraction waste mineral oil hydrogenation catalyst is obtained; wherein, in terms of oxide content, the MoO3 content is 18wt%, the CoO content is 7wt%, the MnO2 content is 3wt%, and the CeO2 content is 0.9wt%; the mixed solution containing molybdenum, cobalt and manganese is a mixed solution containing ammonium molybdate, cobalt nitrate and manganese nitrate; the drying temperature is 108°C; the calcination temperature is 550°C, and the calcination time is 4.5h.

[0063] Example 7

[0064] A method for preparing a novel full-fraction waste mineral oil hydrogenation catalyst comprises the following steps:

[0065] (1) Firstly, aluminum salt and PEG surfactant are dissolved in deionized water to prepare a mixed solution; under stirring, the mixed solution is added dropwise to an ammonium salt aqueous solution, and the pH of the ammonium salt aqueous solution is adjusted to 8; after aging, a precipitate is obtained; and the precipitate is calcined at 620° C. for 5 h to obtain a modified alumina carrier; wherein the number average molecular weight of PEG is 1500; the aluminum salt is aluminum nitrate; the ammonium salt is ammonium bicarbonate; the molar ratio of the ammonium salt to the aluminum salt is 8:1; and the mass ratio of the PEG surfactant to the aluminum salt is 1:1;

[0066] (2) impregnating a modified alumina carrier with a cerium-containing solution, drying and calcining to obtain a primary catalyst; the cerium-containing solution is a cerium nitrate solution; the drying temperature is 115°C; the calcination temperature is 530°C, and the calcination time is 4 hours;

[0067] (3) A primary catalyst is impregnated with a mixed solution containing molybdenum, cobalt and manganese, and after drying and calcination, a full-fraction waste mineral oil hydrogenation catalyst is obtained; wherein, in terms of oxide content, the MoO3 content is 18wt%, the CoO content is 5wt%, the MnO2 content is 3wt%, and the CeO2 content is 0.9wt%; the mixed solution containing molybdenum, cobalt and manganese is a mixed solution containing ammonium molybdate, cobalt nitrate and manganese nitrate; the drying temperature is 108°C; the calcination temperature is 550°C, and the calcination time is 4.5h.

[0068] Example 8

[0069] A method for preparing a novel full-fraction waste mineral oil hydrogenation catalyst comprises the following steps:

[0070] (1) Firstly, aluminum salt and PEG surfactant are dissolved in deionized water to prepare a mixed solution; under stirring, the mixed solution is added dropwise to an ammonium salt aqueous solution, and the pH of the ammonium salt aqueous solution is adjusted to 8; after aging, a precipitate is obtained; and the precipitate is calcined at 620° C. for 5 h to obtain a modified alumina carrier; wherein the number average molecular weight of PEG is 1500; the aluminum salt is aluminum nitrate; the ammonium salt is ammonium bicarbonate; the molar ratio of the ammonium salt to the aluminum salt is 8:1; and the mass ratio of the PEG surfactant to the aluminum salt is 1:1;

[0071] (2) impregnating a modified alumina carrier with a cerium-containing solution, drying and calcining to obtain a primary catalyst; the cerium-containing solution is a cerium nitrate solution; the drying temperature is 115°C; the calcination temperature is 530°C, and the calcination time is 4 hours;

[0072] (3) A primary catalyst is impregnated with a mixed solution containing molybdenum, cobalt and manganese, and after drying and calcination, a full-fraction waste mineral oil hydrogenation catalyst is obtained; wherein, in terms of oxide content, the MoO3 content is 18wt%, the CoO content is 10wt%, the MnO2 content is 3wt%, and the CeO2 content is 0.9wt%; the mixed solution containing molybdenum, cobalt and manganese is a mixed solution containing ammonium molybdate, cobalt nitrate and manganese nitrate; the drying temperature is 108°C; the calcination temperature is 550°C, and the calcination time is 4.5h.

[0073] Example 9

[0074] A method for preparing a novel full-fraction waste mineral oil hydrogenation catalyst comprises the following steps:

[0075] (1) Firstly, aluminum salt and PEG surfactant are dissolved in deionized water to prepare a mixed solution; under stirring, the mixed solution is added dropwise to an ammonium salt aqueous solution, and the pH of the ammonium salt aqueous solution is adjusted to 8; after aging, a precipitate is obtained; and the precipitate is calcined at 620° C. for 5 h to obtain a modified alumina carrier; wherein the number average molecular weight of PEG is 1500; the aluminum salt is aluminum nitrate; the ammonium salt is ammonium bicarbonate; the molar ratio of the ammonium salt to the aluminum salt is 8:1; and the mass ratio of the PEG surfactant to the aluminum salt is 1:1;

[0076] (2) impregnating a modified alumina carrier with a cerium-containing solution, drying and calcining to obtain a primary catalyst; the cerium-containing solution is a cerium nitrate solution; the drying temperature is 115°C; the calcination temperature is 530°C, and the calcination time is 4 hours;

[0077] (3) A primary catalyst is impregnated with a mixed solution containing molybdenum, cobalt and manganese, and after drying and calcination, a full-fraction waste mineral oil hydrogenation catalyst is obtained; wherein, in terms of oxide content, the MoO3 content is 18wt%, the CoO content is 7wt%, the MnO2 content is 2wt%, and the CeO2 content is 0.9wt%; the mixed solution containing molybdenum, cobalt and manganese is a mixed solution containing ammonium molybdate, cobalt nitrate and manganese nitrate; the drying temperature is 108°C; the calcination temperature is 550°C, and the calcination time is 4.5h.

[0078] Example 10

[0079] A method for preparing a novel full-fraction waste mineral oil hydrogenation catalyst comprises the following steps:

[0080] (1) Firstly, aluminum salt and PEG surfactant are dissolved in deionized water to prepare a mixed solution; under stirring, the mixed solution is added dropwise to an ammonium salt aqueous solution, and the pH of the ammonium salt aqueous solution is adjusted to 8; after aging, a precipitate is obtained; and the precipitate is calcined at 620° C. for 5 h to obtain a modified alumina carrier; wherein the number average molecular weight of PEG is 1500; the aluminum salt is aluminum nitrate; the ammonium salt is ammonium bicarbonate; the molar ratio of the ammonium salt to the aluminum salt is 8:1; and the mass ratio of the PEG surfactant to the aluminum salt is 1:1;

[0081] (2) impregnating a modified alumina carrier with a cerium-containing solution, drying and calcining to obtain a primary catalyst; the cerium-containing solution is a cerium nitrate solution; the drying temperature is 115°C; the calcination temperature is 530°C, and the calcination time is 4 hours;

[0082] (3) A primary catalyst is impregnated with a mixed solution containing molybdenum, cobalt and manganese, and after drying and calcination, a full-fraction waste mineral oil hydrogenation catalyst is obtained; wherein, in terms of oxide content, the MoO3 content is 18wt%, the CoO content is 7wt%, the MnO2 content is 4wt%, and the CeO2 content is 0.9wt%; the mixed solution containing molybdenum, cobalt and manganese is a mixed solution containing ammonium molybdate, cobalt nitrate and manganese nitrate; the drying temperature is 108°C; the calcination temperature is 550°C, and the calcination time is 4.5h.

[0083] Embodiment 11

[0084] A method for preparing a novel full-fraction waste mineral oil hydrogenation catalyst comprises the following steps:

[0085] (1) Firstly, aluminum salt and PEG surfactant are dissolved in deionized water to prepare a mixed solution; under stirring, the mixed solution is added dropwise to an ammonium salt aqueous solution, and the pH of the ammonium salt aqueous solution is adjusted to 8; after aging, a precipitate is obtained; and the precipitate is calcined at 620° C. for 5 h to obtain a modified alumina carrier; wherein the number average molecular weight of PEG is 1500; the aluminum salt is aluminum nitrate; the ammonium salt is ammonium bicarbonate; the molar ratio of the ammonium salt to the aluminum salt is 8:1; and the mass ratio of the PEG surfactant to the aluminum salt is 1:1;

[0086] (2) impregnating a modified alumina carrier with a cerium-containing solution, drying and calcining to obtain a primary catalyst; the cerium-containing solution is a cerium nitrate solution; the drying temperature is 115°C; the calcination temperature is 530°C, and the calcination time is 4 hours;

[0087] (3) A primary catalyst is impregnated with a mixed solution containing molybdenum, cobalt and manganese, and after drying and calcination, a full-fraction waste mineral oil hydrogenation catalyst is obtained; wherein, in terms of oxide content, the MoO3 content is 18wt%, the CoO content is 7wt%, the MnO2 content is 3wt%, and the CeO2 content is 0.9wt%; the mixed solution containing molybdenum, cobalt and manganese is a mixed solution containing ammonium molybdate, cobalt nitrate and manganese nitrate; the drying temperature is 108°C; the calcination temperature is 550°C, and the calcination time is 4.5h.

[0088] Comparative Example 1

[0089] A method for preparing a novel full-fraction waste mineral oil hydrogenation catalyst comprises the following steps:

[0090] (1) Firstly, aluminum salt and PEG surfactant are dissolved in deionized water to prepare a mixed solution; under stirring, the mixed solution is added dropwise to an ammonium salt aqueous solution, and the pH of the ammonium salt aqueous solution is adjusted to 8; after aging, a precipitate is obtained; and the precipitate is calcined at 620° C. for 5 h to obtain a modified alumina carrier; wherein the number average molecular weight of PEG is 3000; the aluminum salt is aluminum nitrate; the ammonium salt is ammonium bicarbonate; the molar ratio of the ammonium salt to the aluminum salt is 8:1; and the mass ratio of the PEG surfactant to the aluminum salt is 1:1;

[0091] (2) impregnating a modified alumina carrier with a cerium-containing solution, drying and calcining to obtain a primary catalyst; the cerium-containing solution is a cerium nitrate solution; the drying temperature is 115°C; the calcination temperature is 530°C, and the calcination time is 4 hours;

[0092] (3) A primary catalyst is impregnated with a mixed solution containing molybdenum, cobalt and manganese, and after drying and calcination, a full-fraction waste mineral oil hydrogenation catalyst is obtained; wherein, in terms of oxide content, the MoO3 content is 18wt%, the CoO content is 7wt%, the MnO2 content is 3wt%, and the CeO2 content is 0.9wt%; the mixed solution containing molybdenum, cobalt and manganese is a mixed solution containing ammonium molybdate, cobalt nitrate and manganese nitrate; the drying temperature is 108°C; the calcination temperature is 550°C, and the calcination time is 4.5h.

[0093] Comparative Example 2

[0094] A method for preparing a novel full-fraction waste mineral oil hydrogenation catalyst comprises the following steps:

[0095] (1) Firstly, aluminum salt and PEG surfactant are dissolved in deionized water to prepare a mixed solution; under stirring, the mixed solution is added dropwise to an ammonium salt aqueous solution, and the pH of the ammonium salt aqueous solution is adjusted to 8; after aging, a precipitate is obtained; and the precipitate is calcined at 620° C. for 5 h to obtain a modified alumina carrier; wherein the number average molecular weight of PEG is 1500; the aluminum salt is aluminum nitrate; the ammonium salt is ammonium bicarbonate; the molar ratio of the ammonium salt to the aluminum salt is 8:1; and the mass ratio of the PEG surfactant to the aluminum salt is 1:1;

[0096] (2) A modified alumina carrier is impregnated with a mixed solution containing molybdenum, cobalt, manganese and cerium, and a full-fraction waste mineral oil hydrogenation catalyst is obtained after drying and calcination; wherein, in terms of oxide content, the MoO3 content is 18wt%, the CoO content is 7wt%, the MnO2 content is 3wt%, and the CeO2 content is 0.9wt%; the mixed solution containing molybdenum, cobalt, manganese and cerium is a mixed solution containing ammonium molybdate, cobalt nitrate, manganese nitrate and cerium nitrate; the drying temperature is 108°C; the calcination temperature is 550°C, and the calcination time is 4.5h.

[0097] Comparative Example 3

[0098] A method for preparing a novel full-fraction waste mineral oil hydrogenation catalyst comprises the following steps:

[0099] (1) Firstly, aluminum salt and PEG surfactant are dissolved in deionized water to prepare a mixed solution; under stirring, the mixed solution is added dropwise to an ammonium salt aqueous solution, and the pH of the ammonium salt aqueous solution is adjusted to 8; after aging, a precipitate is obtained; and the precipitate is calcined at 620° C. for 5 h to obtain a modified alumina carrier; wherein the number average molecular weight of PEG is 1500; the aluminum salt is aluminum nitrate; the ammonium salt is ammonium bicarbonate; the molar ratio of the ammonium salt to the aluminum salt is 8:1; and the mass ratio of the PEG surfactant to the aluminum salt is 1:1;

[0100] (2) A modified alumina carrier is impregnated with a mixed solution containing molybdenum, cobalt and manganese, and a full-fraction waste mineral oil hydrogenation catalyst is obtained after drying and calcination; wherein, in terms of oxide content, the MoO3 content is 18wt%, the CoO content is 7wt%, and the MnO2 content is 3.9wt%; the mixed solution containing molybdenum, cobalt and manganese is a mixed solution containing ammonium molybdate, cobalt nitrate and manganese nitrate; the drying temperature is 108°C; the calcination temperature is 550°C, and the calcination time is 4.5h.

[0101] Comparative Example 4

[0102] A method for preparing a novel full-fraction waste mineral oil hydrogenation catalyst comprises the following steps:

[0103] (1) Firstly, aluminum salt and PEG surfactant are dissolved in deionized water to prepare a mixed solution; under stirring, the mixed solution is added dropwise to an ammonium salt aqueous solution, and the pH of the ammonium salt aqueous solution is adjusted to 8; after aging, a precipitate is obtained; and the precipitate is calcined at 620° C. for 5 h to obtain a modified alumina carrier; wherein the number average molecular weight of PEG is 1500; the aluminum salt is aluminum nitrate; the ammonium salt is ammonium bicarbonate; the molar ratio of the ammonium salt to the aluminum salt is 8:1; and the mass ratio of the PEG surfactant to the aluminum salt is 1:1;

[0104] (2) impregnating a modified alumina carrier with a cerium-containing solution, drying and calcining to obtain a primary catalyst; the cerium-containing solution is a cerium nitrate solution; the drying temperature is 115°C; the calcination temperature is 530°C, and the calcination time is 4 hours;

[0105] (3) A primary catalyst is impregnated with a mixed solution containing molybdenum and cobalt, and after drying and calcination, a full-fraction waste mineral oil hydrogenation catalyst is obtained; wherein, in terms of oxide content, the MoO3 content is 18wt%, the CoO content is 7wt%, and the CeO2 content is 3.9wt%; the mixed solution containing molybdenum and cobalt is a mixed solution containing ammonium molybdate and cobalt nitrate; the drying temperature is 108°C; the calcination temperature is 550°C, and the calcination time is 4.5h.

[0106] Comparative Example 5

[0107] A method for preparing a novel full-fraction waste mineral oil hydrogenation catalyst comprises the following steps:

[0108] (1) Firstly, aluminum salt and PEG surfactant are dissolved in deionized water to prepare a mixed solution; under stirring, the mixed solution is added dropwise to an ammonium salt aqueous solution, and the pH of the ammonium salt aqueous solution is adjusted to 8; after aging, a precipitate is obtained; and the precipitate is calcined at 620° C. for 5 h to obtain a modified alumina carrier; wherein the number average molecular weight of PEG is 1500; the aluminum salt is aluminum nitrate; the ammonium salt is ammonium bicarbonate; the molar ratio of the ammonium salt to the aluminum salt is 8:1; and the mass ratio of the PEG surfactant to the aluminum salt is 1:1;

[0109] (2) impregnating a modified alumina carrier with a cerium-containing solution, drying and calcining to obtain a primary catalyst; the cerium-containing solution is a cerium nitrate solution; the drying temperature is 115°C; the calcination temperature is 530°C, and the calcination time is 4 hours;

[0110] (3) A primary catalyst is impregnated with a mixed solution containing molybdenum, cobalt and manganese, and after drying and calcination, a full-fraction waste mineral oil hydrogenation catalyst is obtained; wherein, in terms of oxide content, the MoO3 content is 18wt%, the CoO content is 7wt%, the MnO2 content is 3wt%, and the CeO2 content is 0.2wt%; the mixed solution containing molybdenum, cobalt and manganese is a mixed solution containing ammonium molybdate, cobalt nitrate and manganese nitrate; the drying temperature is 108°C; the calcination temperature is 550°C, and the calcination time is 4.5h.

[0111] Comparative Example 6

[0112] A method for preparing a novel full-fraction waste mineral oil hydrogenation catalyst comprises the following steps:

[0113] (1) Firstly, aluminum salt and PEG surfactant are dissolved in deionized water to prepare a mixed solution; under stirring, the mixed solution is added dropwise to an ammonium salt aqueous solution, and the pH of the ammonium salt aqueous solution is adjusted to 8; after aging, a precipitate is obtained; and the precipitate is calcined at 620° C. for 5 h to obtain a modified alumina carrier; wherein the number average molecular weight of PEG is 1500; the aluminum salt is aluminum nitrate; the ammonium salt is ammonium bicarbonate; the molar ratio of the ammonium salt to the aluminum salt is 8:1; and the mass ratio of the PEG surfactant to the aluminum salt is 1:1;

[0114] (2) impregnating a modified alumina carrier with a cerium-containing solution, drying and calcining to obtain a primary catalyst; the cerium-containing solution is a cerium nitrate solution; the drying temperature is 115°C; the calcination temperature is 530°C, and the calcination time is 4 hours;

[0115] (3) A primary catalyst is impregnated with a mixed solution containing molybdenum, cobalt and manganese, and after drying and calcination, a full-fraction waste mineral oil hydrogenation catalyst is obtained; wherein, in terms of oxide content, the MoO3 content is 18wt%, the CoO content is 7wt%, the MnO2 content is 3wt%, and the CeO2 content is 2wt%; the mixed solution containing molybdenum, cobalt and manganese is a mixed solution containing ammonium molybdate, cobalt nitrate and manganese nitrate; the drying temperature is 108°C; the calcination temperature is 550°C, and the calcination time is 4.5h.

[0116] Performance test: The BET method was used to test the specific surface area and average pore size of the full-fraction waste mineral oil hydrogenation catalyst prepared in the embodiment and the comparative example. Then, the full-fraction waste mineral oil hydrogenation catalyst prepared in the embodiment and the comparative example was sulfurized and introduced into the full-fraction waste lubricating oil for hydrogenation reaction. The specific process conditions were: reaction temperature 320°C, hydrogen pressure 4.5Mpa, mass space velocity 1.0h -1, hydrogen to oil volume ratio is 1000.

[0117]

[0118] As can be seen from Table 1, the present invention adopts polyethylene glycol as a surfactant and prepares a high specific surface area catalyst carrier by a coprecipitation process. By selecting polyethylene glycol with a number average molecular weight of 800-2000 as a surfactant, the dispersion of the precipitate can be promoted, which is conducive to the formation of interstitial pores. By pre-depositing cerium salts, the cerium oxide auxiliary agent significantly promotes the dispersion of active components in the catalyst, weakens the interaction between the metal and the carrier, and increases the specific surface area of ​​the catalyst, thereby increasing the number of active species on the catalyst surface. The addition of manganese can enhance the interaction between the various components of the catalyst, and in particular, the formation of manganese oxide can effectively promote the dispersion of active components and prevent catalyst sintering, thereby effectively improving the activity of the catalyst, and the addition of manganese oxide reduces the particle size of platinum and increases the dispersion of platinum. The catalyst has a higher specific surface area and pore size, high catalytic activity, and effectively improves the desulfurization and denitrification rates of waste mineral oil. The embodiment and the comparative example are all compared using a single factor. Specifically, compared with Example 11, the difference of Comparative Example 1 is only that the molecular weight of PEG used is too large, which is not conducive to the dispersion of precipitation, and it is easy to cause the mechanical strength of the carrier to be low, and the structural collapse phenomenon is easy to occur during high-temperature calcination. Similarly, relative to Example 11, Comparative Examples 2-4 show that the cerium additive can improve the dispersion of the active component on the carrier surface and improve the catalytic activity. Metallic manganese can change the synergistic effect between different metals and thus change the catalytic selectivity; adding both at the same time can play a synergistic effect. Comparative Examples 5-6 show that when the amount of cerium oxide is too small, the dispersion effect is limited. Although the catalyst performance is improved to a certain extent and can meet the use requirements of ordinary hydrogenation catalysts, it cannot meet the harsh conditions of full-fraction waste mineral oil hydrogenation catalysts, and the desulfurization and denitrification rates are low. When the amount of cerium oxide is too much, its performance is not further improved. This may be because the excessive amount of cerium oxide leads to an increase in grain size, a decrease in specific surface area and pore size, and affects the catalyst performance.

[0119] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A method for preparing a full-fraction waste mineral oil hydrogenation catalyst, characterized in that: The following steps are involved: (1) Using aluminum salt, ammonium salt and PEG surfactant as raw materials, a modified alumina carrier is prepared by coprecipitation and calcination process; wherein the number average molecular weight of PEG is 1000-1500; (2) impregnating a modified alumina carrier with a cerium-containing solution, drying and calcining to obtain a primary catalyst; (3) A primary catalyst is impregnated with a mixed solution containing molybdenum, cobalt and manganese, and after drying and calcination, a full-fraction waste mineral oil hydrogenation catalyst is obtained; wherein, in terms of oxide content, the MoO3 content is 16-20wt%, the CoO content is 6.5-8.5wt%, the MnO2 content is 2.5-3.4wt%, and the CeO2 content is 0.5-1.2wt%.

2. The method for preparing a full-fraction waste mineral oil hydrogenation catalyst according to claim 1, characterized in that: In step (1), the aluminum salt is any one of aluminum nitrate and aluminum chloride; and the ammonium salt is any one of ammonium bicarbonate and ammonium chloride.

3. The method for preparing a full-fraction waste mineral oil hydrogenation catalyst according to claim 1, characterized in that: In step (1), the molar ratio of ammonium salt to aluminum salt is (6-9):1; the mass ratio of PEG surfactant to aluminum salt is (0.8-1.2):

1.

4. The method for preparing a full-fraction waste mineral oil hydrogenation catalyst according to claim 1, characterized in that: The specific preparation process of the modified alumina carrier in step (1) is: First, aluminum salt and PEG surfactant were dissolved in deionized water to prepare a mixed solution; Under stirring, the mixed solution is added dropwise to the ammonium salt aqueous solution, and the pH of the ammonium salt aqueous solution is adjusted to 8-9; After aging, precipitation is obtained; The precipitate is calcined at 580-650°C for 4-6 hours to obtain a modified alumina carrier.

5. The method for preparing a full-fraction waste mineral oil hydrogenation catalyst according to claim 1, characterized in that: The cerium-containing solution in step (2) is a cerium nitrate solution.

6. The method for preparing a full-fraction waste mineral oil hydrogenation catalyst according to claim 1, characterized in that: In step (2), the drying temperature is 110-120°C; the roasting temperature is 500-550°C, and the roasting time is 3.5-5h.

7. The method for preparing a full-fraction waste mineral oil hydrogenation catalyst according to claim 1, characterized in that: The mixed solution containing molybdenum, cobalt and manganese in step (3) is a mixed solution containing ammonium molybdate, cobalt nitrate and manganese nitrate.

8. The method for preparing a full-fraction waste mineral oil hydrogenation catalyst according to claim 1, characterized in that: In step (3), the drying temperature is 105-110°C; the roasting temperature is 500-600°C, and the roasting time is 4-5h.

9. A full-fraction waste mineral oil hydrogenation catalyst, characterized in that: The catalyst is prepared by the method for preparing a full-fraction waste mineral oil hydrogenation catalyst as described in any one of claims 1 to 8.

Images