A method for preparing a molybdenum-based catalyst and its application
Through the preparation method of molybdenum-based catalyst, the problems of high energy consumption and high catalyst harshness in traditional crude oil processing technology are solved, and the efficient self-sulfurization and hydrogenation performance of molybdenum-based catalysts in slurry beds are achieved, which is suitable for various crude oils , reducing the harshness of crude oil-making chemical processes.
Patent Information
- Application Number
- CN202410210652.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-02-27
- Publication Date
- 2025-01-03
- Estimated Expiration
- 2044-02-27
AI Technical Summary
The traditional crude oil processing process has high comprehensive energy consumption, large equipment investment, and high catalyst harshness. It is impossible to effectively treat crude oil with high metal content, large density, wide distillation range and high heavy component content, and cannot achieve one-step process chemicals.
The preparation method of molybdenum-based catalyst is adopted to obtain an oil-soluble molybdenum-based catalyst by reacting molybdenum source, long-chain fatty acid amide, organic solvent, and vulcanizing agent in a one-pot method. The process is simple and reliable. The catalyst can be self-sulfurized in a slurry bed reactor. It is suitable for Hydrogenation of crude oil of various qualities to improve quality.
It realizes the high dispersion and good hydrogenation performance of the catalyst, reduces the asphaltene content, improves the yield of light oil, reduces the amount of coke, is suitable for crude oil of various quality, and reduces the harshness of crude oil-making chemical processes. .
Smart Images
Figure SMS_1 
Figure SMS_2 
Figure SMS_3
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of catalyst preparation, and in particular to a preparation method of a molybdenum-based catalyst and application thereof. Background Art
[0002] The main products of the traditional crude oil processing process are mainly refined oil. In the future, affected by the development of new energy vehicles based on hydrogen and electric energy, the market demand for automotive fuel oil will be further reduced, and the consumption demand for olefins and aromatics of various materials will continue to grow. The process route of maximizing the production of chemical raw materials in the traditional refining process mainly cuts crude oil into light and heavy fractions through atmospheric and vacuum distillation. The light fraction oil is directly produced through steam cracking, reforming, aromatization and other devices to produce olefin aromatics, and the heavy fraction oil is lightened through fixed bed hydrocracking, slurry bed (suspended bed) hydrocracking and other devices to maximize the production of olefin aromatics. The above process scheme has a long overall process, high comprehensive energy consumption, and large overall device investment, which is not conducive to the structural transformation of traditional stock refineries. At present, two typical technologies have been formed: steam cracking and catalytic cracking. However, due to the high severity of the catalyst, the harsh operation of the cracking furnace process, and the poor adaptability to the raw materials, it is impossible to directly produce chemicals in one step for crude oil with high metal content, high density, wide distillation range, and high heavy component content. Therefore, upgrading crude oil through slurry bed hydrogenation to reduce metal content, sulfur and nitrogen content, reduce asphaltene content, and increase the proportion of light oil can provide effective raw materials for the one-step production of chemicals from crude oil, which is of great significance.
[0003] Slurry bed hydrogenation is a process in which a small amount of catalyst is dispersed in the raw material in the form of solid powder or liquid. After the raw material and hydrogen are heated to the reaction temperature, they pass through the reactor from bottom to top in the form of a gas, liquid and solid three-phase slurry. It has the advantages of strong raw material adaptability, simple process and high conversion rate.
[0004] The key to the development of slurry bed hydrocracking process lies in the continuous progress of high-quality hydrogenation catalysts, among which oil-soluble catalysts can be effectively dissolved in heavy raw materials, show excellent hydrogenation effect and effectively inhibit coke formation, and are ideal catalysts. Chinese patent CN201610804914.2 discloses the use of soluble salts of Mo or W to precipitate at 40-100°C to obtain active metal precursors, and react with C6-C20 organic acids to obtain oil-soluble catalysts. Chinese patent CN201410216485.8 discloses the use of reduced metals and organic amines to react to obtain oil-soluble catalysts. Chinese patent CN202010553349.3 metal acid salts are mixed evenly with surfactants, and the mixture is obtained after sufficient grinding to obtain a suspended bed hydrogenation catalyst. U.S. Patent No. 4125455 discloses the use of metal salts composed of VIB metals (molybdenum, tungsten, chromium) of C7-C32 fatty acids as catalysts for hydrogenation. 590ppm of molybdenum octoate is added as a catalyst, and the hydrogenation effect is good at 430°C and 13.7MPa. Most of these catalysts have complex synthesis routes and need to be sulfurized separately, which reduces the efficiency of slurry bed crude oil hydrogenation and increases equipment investment. Summary of the invention
[0005] In view of this, the present invention proposes a preparation method of a molybdenum-based catalyst and its application. The preparation method has a simple and reliable process, low requirements on temperature and equipment, and simple operation. The catalyst can be self-sulfurized into active components in situ in a slurry bed reactor. The active metal is ultra-highly dispersed in the crude oil, has good hydrogenation performance and coke suppression performance, and is suitable for slurry bed hydrogenation and quality upgrading of crude oil of various qualities.
[0006] To achieve the above object, the present invention provides the following technical solution: a method for preparing a molybdenum-based catalyst, comprising the following steps:
[0007] S1, taking a molybdenum source, a long-chain fatty acid amide, an organic solvent, and a vulcanizing agent and reacting them in one pot to obtain a molybdenum-based precursor mixed solution;
[0008] S2. Separating the molybdenum-based precursor mixed solution to obtain an oil-soluble molybdenum-based catalyst.
[0009] Preferably, in step S1, a molybdenum source, a long-chain fatty acid amide, an organic solvent, and a vulcanizing agent are added together into a reactor, and stirred and heated at 85° C. to 150° C. for 6 to 12 hours; in step S2, the solution obtained in S1 is cooled, allowed to stand for stratification, and the aqueous phase is removed to obtain an organic solvent-dispersed oil-soluble molybdenum-based catalyst.
[0010] Preferably, the molybdenum source in step S1 is any one or a combination of molybdenum trioxide, ammonium heptamolybdate, ammonium tetramolybdate, molybdic acid, molybdenum acetylacetonate, and molybdenum hexacarbonyl.
[0011] Preferably, in step S1, the long-chain fatty acid amide is any one or more of palmitic acid diethanolamide, lauric acid diethanolamide, stearic acid diethanolamide, oleic acid diethanolamide, behenic acid diethanolamide, arachidic acid diethanolamide, nonanoic acid diethanolamide, capric acid diethanolamide, myristic acid diethanolamide, lignoceric acid diethanolamide, ceric acid diethanolamide, melissic acid diethanolamide, lacquer wax acid diethanolamide, dodecenoic acid diethanolamide, eicosatrienoic acid diethanolamide, and erucic acid diethanolamide.
[0012] Preferably, the organic solvent in step S1 is any one or more of toluene, petroleum ether, xylene, DMF, and n-butanol.
[0013] Preferably, the sulfiding agent in step S1 is one or more of ammonium sulfide, sodium sulfide, sodium hydrosulfide, sodium polysulfide, and thioacetamide.
[0014] Preferably, the molar ratio of the molybdenum source, the long-chain fatty acid amide, the organic solvent, and the vulcanizing agent is 1:0.6-1:5-10:4-10.
[0015] The present invention also proposes an application of a molybdenum-based catalyst, which is prepared by the above-mentioned preparation method, and is hydrogenated in a crude oil slurry bed over a molybdenum-based catalyst before the crude oil is subjected to atmospheric and vacuum distillation or before entering a crude oil direct chemical production device.
[0016] Preferably, the catalyst addition amount is 50-1200 ppm, the reaction temperature is 330-460°C, the reaction pressure is 5-20 MPa, and the liquid hourly volume space velocity is 0.2-1.5 h -1 , the volume ratio of hydrogen to raw material is 300-1500.
[0017] Preferably, the crude oil is one or more of paraffin-based crude oil, intermediate-based crude oil, and naphthenic crude oil.
[0018] Compared with the existing technology, the present invention provides a preparation method and application of a molybdenum-based catalyst preparation method, which has the following beneficial effects:
[0019] The present invention adopts a one-pot reaction of a molybdenum source, a long-chain fatty acid amide, an organic solvent, and a vulcanizing agent to obtain a molybdenum-based precursor mixed solution, and the liquid is separated to directly obtain an oil-soluble molybdenum-based catalyst dispersed in an organic solvent. The preparation method has a simple and reliable process, low requirements on temperature and equipment, and simple operation. When the catalyst is used, there is no need to add an additional vulcanizing agent. The catalyst can be self-sulfurized in situ in a slurry bed reactor to form an active component. The active metal is highly dispersed in the crude oil, has good hydrogenation performance and coke suppression performance, is suitable for slurry bed hydrogenation and upgrading of crude oil of various qualities, can provide high-quality raw materials for the direct production of chemicals from crude oil, and has a very broad application prospect. DETAILED DESCRIPTION
[0020] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.
[0021] The experimental methods in the examples of this application are all conventional methods unless otherwise specified. The experimental materials used in the examples are all purchased from conventional reagent stores unless otherwise specified.
[0022] Example 1
[0023] Weigh 30g of molybdenum oxide, add 100ml of water, weigh 30g of oleic acid diethanolamide, 120g of toluene, and 70g of thioacetamide, add them to the above solution in sequence, heat to 145°C and stir to react for 3h. Centrifuge the obtained solution, separate the liquid and take the oil phase, and prepare an oil-soluble molybdenum-based catalyst, named M-1.
[0024] Example 2
[0025] Weigh 30g of ammonium heptamolybdate, add 80ml of water, weigh 30g of palmitic acid diethanolamide, 150g of toluene, and 80g of sodium sulfide, add them to the above solution in sequence, heat to 130°C and stir to react for 4h. Centrifuge the obtained solution, separate the liquid and take the oil phase, and prepare an oil-soluble molybdenum-based catalyst, named M-2.
[0026] Example 3
[0027] Weigh 30g of molybdenum oxide, add 100ml of water, weigh 30g of lauric acid diethanolamide, 150g of toluene, and 70g of sodium hydrosulfide, add them to the above solution in sequence, heat to 150°C and stir to react for 3h. Centrifuge the obtained solution, separate the liquid and take the oil phase, and prepare an oil-soluble molybdenum-based catalyst, named M-3.
[0028] Example 4
[0029] Weigh 30g of ammonium heptamolybdate, add 100ml of water, weigh 30g of stearic acid diethanolamide, 160g of petroleum ether, and 70g of thioacetamide, add them to the above solution in sequence, heat to 150°C and stir to react for 3h. Centrifuge the obtained solution, separate the liquid and take the oil phase, and obtain an oil-soluble molybdenum-based catalyst, named M-4.
[0030] Comparative Example 1
[0031] Comparative Example 1 is a commercial molybdenum octanoate catalyst purchased
[0032] The oil-soluble Mo catalyst of the present invention can be used in the slurry bed hydrocracking process of various crude oils. The method of using the oil-soluble Mo-based catalyst is as follows: the oil-soluble Mo-based catalyst is directly added to the crude oil, and the active metal Mo sulfide is generated by self-sulfurization during the heating process, which has excellent hydrogenation activity. The amount of the catalyst added is 50 to 1200 ppm (in terms of metal Mo), the reaction temperature is 330 to 460° C., the reaction pressure is 5 to 20 MPa, and the liquid hourly volume space velocity is 0.2 to 1.5 h -1 , the volume ratio of hydrogen to raw material is 300-1500.
[0033] Table 1 Properties of Saudi crude oil
[0034]
[0035]
[0036] The oil-soluble platinum-based catalysts (M-1, M-2, M-3, M-4) and molybdenum octanoate catalysts in Examples 1, 2, 3 and 4 were used as raw materials (properties are shown in Table 1). The reaction temperature was 390° C., the hydrogen pressure was 7 MPa, the catalyst addition amount was 200 ug / g in terms of metal platinum, and the liquid hourly volume space velocity was 1 h -1 , the volume ratio of hydrogen to feedstock is 1200. The evaluation results of Saudi crude oil hydrogenation upgrading with different oil-soluble molybdenum-based catalysts under the same reaction conditions are shown in Table 2.
[0037] Table 2 Evaluation results of Saudi crude oil hydrogenation test
[0038]
[0039]
[0040] It can be seen from the data in Table 2 that the oil-soluble molybdenum-based catalyst prepared by the present invention has excellent hydrogenation performance. At a reaction temperature of 390°C, an initial hydrogen pressure of 7MPa, a catalyst dosage of 200μg / g (in terms of metal), and a liquid hourly volume space velocity of 1h -1 , under the condition that the volume ratio of hydrogen to raw material is 1200, the asphaltene content in oil products can be effectively reduced, the light oil yield is increased by 7 percentage points, and the coke amount is less than 0.1wt%. Compared with the commercial molybdenum isooctanoate catalyst, the oil-soluble molybdenum-based catalyst provided by the present invention has better activity, and the crude oil after hydrogenation and reforming can be directly used in the crude oil chemical process, which reduces the requirements of crude oil steam cracking and catalytic cracking on the severity of oil products.
[0041] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for a person skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to replace some of the technical features therein with equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions claimed to be protected by the present invention.
Claims
1. A method for preparing a molybdenum-based catalyst, characterized in that: The steps include: S1, taking a molybdenum source, a long-chain fatty acid amide, an organic solvent, and a vulcanizing agent and reacting them in one pot to obtain a molybdenum-based precursor mixed solution; S2, separating the molybdenum-based precursor mixed solution to obtain an oil-soluble molybdenum-based catalyst; In step S1, a molybdenum source, a long-chain fatty acid amide, an organic solvent, and a vulcanizing agent are added to a reaction kettle, and stirred and heated at 85° C. to 150° C. for 6 to 12 hours; in step S2, the solution obtained in S1 is cooled, allowed to stand for stratification, and the aqueous phase is removed to obtain an organic solvent-dispersed oil-soluble molybdenum-based catalyst; The molybdenum source in step S1 is any one or a combination of molybdenum trioxide, ammonium heptamolybdate, ammonium tetramolybdate, molybdic acid, molybdenum acetylacetonate, and molybdenum hexacarbonyl; In step S1, the long-chain fatty acid amide is palmitic acid diethanolamide, lauric acid diethanolamide, stearic acid diethanolamide, oleic acid diethanolamide, behenic acid diethanolamide, arachidic acid diethanolamide, nonanoic acid diethanolamide, capric acid diethanolamide, myristic acid diethanolamide, wood wax acid diethanolamide, wax acid diethanolamide, melissic acid diethanolamide, shellac wax acid diethanolamide, decenoic acid diethanolamide, eicosatrienoic acid diethanolamide, erucic acid diethanolamide, any one or more; The sulfiding agent in S1 is one or more of ammonium sulfide, sodium sulfide, sodium hydrosulfide, sodium polysulfide, and thioacetamide.
2. The method for preparing a platinum-based catalyst according to claim 1, characterized in that: In step S1, the organic solvent is any one or more of toluene, petroleum ether, xylene, DMF, and n-butanol.
3. The preparation method of a platinum-based catalyst according to claim 1, characterized in that: The molar ratio of the molybdenum source, the long-chain fatty acid amide, the organic solvent and the vulcanizing agent is 1:0.6~1:5~10:4~10.
4. An application of a molybdenum-based catalyst, prepared by the preparation method according to any one of claims 1 to 3, characterized in that: Before the crude oil is subjected to atmospheric and vacuum distillation or before it enters the crude oil direct chemical production unit, it is hydrotreated in a crude oil slurry bed over a molybdenum-based catalyst.
5. The use of a molybdenum-based catalyst according to claim 4, characterized in that: The catalyst addition amount is 50~1200ppm, the reaction temperature is 330~460℃, the reaction pressure is 5~20MPa, and the liquid hourly volume space velocity is 0.2~1.5h -1 , the volume ratio of hydrogen to raw materials is 300~1500.
6. Use of a molybdenum-based catalyst according to claim 4 or 5, characterized in that: The crude oil is one or more of paraffin-based crude oil, intermediate-based crude oil, and naphthenic crude oil.