CN111644208B - Preparation method and application of oil-soluble suspension bed hydrogenation catalyst - Google Patents

Abstract

The invention relates to a preparation method and application of an oil-soluble suspended bed hydrogenation catalyst, belonging to the technical field of petroleum processing; the preparation method comprises the following steps: uniformly mixing a metal salt and a surfactant, and thoroughly grinding; putting the above-mentioned mixture into put into a vacuum drying oven, and heat to obtain a catalyst precursor; fully grind the above catalyst precursor, dissolve it in oil, and obtain a suspension bed hydrogenation catalyst. The preparation method of the oil-soluble suspended bed hydrogenation catalyst of the present invention adopts a low-temperature solid-phase reaction method, has simple preparation technology, avoids the use of various solvents, and does not discharge waste water and waste gas. At the same time, it consumes less energy, has low requirements for production equipment, and requires less investment in equipment.

Description

A kind of preparation method and application of oil-soluble suspended bed hydrogenation catalyst

technical field

The invention belongs to the technical field of petroleum processing, and in particular relates to a preparation method and application of an oil-soluble suspended bed hydrogenation catalyst.

Background technique

With the continuous growth of oil demand and the shrinking of light crude oil reserves that are easy to be exploited in shallow layers, the crude oil becomes heavier and inferior, and the average content of residual oil can reach more than 50%. Residual oil is composed of saturates, aromatics, colloids and asphaltenes. How to improve the conversion rate of residual oils (especially colloids and asphaltene in residual oils) is the key to efficient utilization of petroleum resources, improvement of energy efficiency, reduction of environmental pollution and my country's The key to dependence on international crude oil, one of the effective ways to crack this key is to develop heavy oil hydrogenation technology. Due to the presence of colloidal asphaltenes and trace metals that are prone to coke formation in the residual oil, this makes the supported catalysts used in the hydroconversion of heavy oil, especially in the process of fixed bed heavy oil hydrogenation, prone to coking and metal Deposition causes problems such as rapid catalyst deactivation and short life. The heavy oil suspension bed hydrogenation process is a heavy oil lightening process that uses non-supported catalysts to treat inferior residues (high metals, high carbon residues, high sulfur, high nitrogen, and high viscosity), with high conversion rates and high light oil yields , while effectively avoiding catalyst deactivation caused by coke deposition.

The heavy oil suspended bed hydrogenation process has not yet been industrialized on a large scale, and its technological breakthroughs mainly focus on the development of high-performance catalysts. The early heavy oil suspension bed hydrogenation process mainly used solid particles or powders as catalysts. The catalyst activity was low, the dosage was large, and the equipment was severely worn. At the same time, the tail oil contained a large amount of solid particles, which made it difficult to process and utilize. Oil-soluble catalysts can be evenly dispersed in heavy oil, fully contact with heavy oil and hydrogen, have high catalytic activity, less catalyst addition, and lower operating costs, so they are favored by experts, scholars and enterprises at home and abroad.

Chinese patent CN201410216485.8 discloses that metal element compounds obtained in a reduced state are used as metal sources to react with organic amines and carbon disulfide in a reaction medium at elevated temperatures, and the obtained products are filtered and washed to obtain an oil-soluble composite hydrocracking catalyst. Chinese patent CN201510848631.3 discloses the joint reaction of metal salts with organic carboxylic acids, alcohols and vulcanizing agents to prepare oil-soluble catalysts. Chinese patent CN01106013.1 discloses the preparation of an oil-soluble catalyst by reacting Mo, W metals with benzene and its derivatives. Chinese patent 201510275523.1 discloses the use of nickel nitrate, ammonium molybdate, and adding a small amount of ethylene glycol. After adjusting the pH value, a precipitate is obtained in the aqueous solution, and the precipitate is filtered and mixed with oleic acid, and heated for reaction to prepare an oil-soluble bimetallic catalyst. Although the above-mentioned oil-soluble catalysts all exhibit excellent hydrocracking performance and coke suppression performance, organic solvents or organic media are used as reactants or reaction sites in the preparation process, which pollutes the environment and easily causes personal injury, and also requires filtration. , washing and purification steps, the preparation process is loaded down with trivial details.

Therefore, it is of great significance to prepare an oil-soluble suspended bed hydrogenation catalyst with high activity using non-toxic and harmless reactants and simplified reaction steps.

Contents of the invention

In view of the above-mentioned defects of the existing oil-soluble catalysts, the object of the present invention is to propose a preparation method and application of an oil-soluble suspended bed hydrogenation catalyst, which can solve the defects of safety and environmental protection and complicated preparation process in the prior art.

The principle that the present invention is based on is as follows: the preparation method of the oil-soluble suspended bed hydrogenation catalyst of the present invention uses a low-temperature solid-phase reaction method, adopts metal salts and long-chain alkyl quaternary ammonium salt surfactants to stir and mix evenly, fully Grind for a long enough time to allow the above two to fully contact and react. When in use, the above-mentioned catalyst precursor is ground and dissolved in petroleum fractions, and directly added to the reactor to generate a catalytic hydrogenation active phase in situ in the reactor without separation, dispersion and pre-sulfurization of the catalyst. On the premise of saving operating costs and simplifying operating steps, the catalyst is excellently dispersed at the reaction temperature and can reach molecular level dispersion, and the amount of catalyst used is less when the same treatment effect is achieved.

Based on above-mentioned principle, technical scheme of the present invention is as follows:

One of the present invention provides a kind of preparation method of oil-soluble suspended bed hydrogenation catalyst, comprises the following steps:

S101: Mix the main agent metal salt and surfactant evenly, and grind them sufficiently to obtain the mixture; the surfactant is a long-chain alkyl quaternary ammonium salt surfactant; the main agent metal salt is heptamolybdic acid One or a combination of ammonium, ammonium tetramolybdate, sodium heptamolybdate, ammonium tungstate, ammonium metatungstate and sodium tungstate;

S102: Put the above mixture into a vacuum drying oven, heat and dry to obtain a catalyst precursor;

S103: Grinding the above catalyst precursor sufficiently, dissolving it in oil, to obtain a suspension bed hydrogenation catalyst.

Further, the step S101 also includes an auxiliary metal salt, which is uniformly mixed with the main agent metal salt and a surfactant and ground; the auxiliary metal salt is at least cobalt acetate, cobalt carbonate, and cobalt nitrate , one of nickel carbonate and nickel nitrate; the metal molar ratio of the metal salt of the main agent and the metal salt of the auxiliary agent is 3:1-1:1.

Further, the long-chain alkyl quaternary ammonium salt surfactants include at least one or a combination of anionic surfactants, cationic surfactants and zwitterionic surfactants; further preferably, the anionic In the surfactant, the number of carbon atoms of the multi-carbon alkyl chain is 5-18, and the chain number of the multi-carbon alkyl chain is 1-4; more preferably, the long-chain alkyl quaternary ammonium salt surfactant Dioctadecyl dimethyl ammonium chloride.

Further, the step S101 includes the following steps:

S1011: Fully grind a single main agent metal salt or a mixture of main agent metal salt and auxiliary agent metal salt for 10min-30min;

S1012: Fully grind the long-chain alkyl quaternary ammonium salt surfactant for 10min-30min, the amount of long-chain alkyl quaternary ammonium salt surfactant is determined according to the total charge of metal ions in the main agent metal salt , that is, the total number of negative charges of the long-chain alkylamine ions is consistent with the total number of positive charges of the metal ions, so that the final product is electrically neutral.

S1013: Stir and mix the above two evenly, and fully grind for 0.5h-1h.

Further, in the step S102, the heating and drying temperature is 60°C-180°C, and the heating and drying time is 1h-5h.

Further, in the step S103, the oil product includes at least one of lubricating base oil, straight-run diesel oil, catalytically cracked diesel oil, coker diesel oil and liquid wax oil.

The second aspect of the present invention is to propose the oil-soluble suspended bed hydrogenation catalyst obtained by the above preparation method.

The third aspect of the present invention is to propose the application of the above-mentioned oil-soluble suspension bed hydrogenation catalyst in the suspension bed hydrogenation process. When in use, take a certain volume of oil-soluble suspension bed hydrogenation catalyst and directly add it to inferior heavy oil. During the reaction, sulfur-containing compounds in the heavy oil are used to generate hydrogenation active components in situ. The hydrogenation activity is excellent. The amount of catalyst used is calculated as metal. 50μg/g-2000μg/g; the operating conditions of the suspension bed hydrogenation reactor are: reaction pressure 5MPa-25MPa, reaction temperature 380℃-480℃, volume space velocity 0.2h ^-1 -1.5h ^-1 , volume ratio of hydrogen to oil 200-1000.

Compared with the prior art, the preparation method of the oil-soluble suspended bed hydrogenation catalyst of the present invention has the following beneficial effects:

(1) The low-temperature solid-phase reaction method is adopted, that is, the reactants are all in the solid phase at room temperature, and there is no solution system involved, which avoids tedious and complicated operations such as filtration and purification. The preparation cost of the catalyst is convenient for low-cost large-scale industrial production.

(2) The oil-soluble suspended bed hydrogenation catalyst prepared by the present invention is dissolved in oil in advance, and directly added to the reaction during the reaction, which can quickly and stably reach molecular level dispersion, thereby reducing the start-up time and catalyst usage.

Detailed ways

The present invention will be described in detail below through specific examples, but the use and purpose of these exemplary embodiments are only used to exemplify the present invention, and do not constitute any form of any limitation to the actual protection scope of the present invention, nor will the present invention The scope of protection is limited to this.

Example 1

A kind of preparation method of oil-soluble Mo base suspension bed hydrogenation catalyst, its preparation method comprises the steps:

Weigh 1.236g of ammonium molybdate tetrahydrate, and grind vigorously for 10 minutes; weigh 3.519g of dioctadecyldimethylammonium chloride, and grind vigorously for 10 minutes; stir and mix the above two evenly, and grind vigorously for 0.5h.

The above product was put into a vacuum drying oven, and dried in vacuum at 180° C. for 5 h.

The catalyst precursor was taken out and thoroughly ground and dissolved in 100 mL of white oil (lubricating base oil) to obtain an oil-soluble Mo-based suspension-bed hydrogenation catalyst.

Example 2

A kind of preparation method of oil-soluble W-based suspension bed hydrogenation catalyst, its preparation method comprises the steps:

Weigh 1.319g of sodium tungstate dihydrate, and grind vigorously for 10 minutes; weigh 4.692g of dioctadecyldimethylammonium chloride, and grind vigorously for 10 minutes; stir and mix the above two evenly, and grind vigorously for 0.5h.

The above product was put into a vacuum drying oven, and dried in vacuum at 180° C. for 5 h.

The catalyst precursor was taken out and thoroughly ground and dissolved in 100 mL of white oil (lubricating base oil) to obtain an oil-soluble W-based suspension-bed hydrogenation catalyst.

Example 3

A kind of preparation method of oil-soluble CoMo base suspension bed hydrogenation catalyst, its preparation method comprises the steps:

Weigh 1.236g of ammonium molybdate tetrahydrate, 0.747g of cobalt acetate tetrahydrate, and grind vigorously for 10 minutes; weigh 3.519g of dioctadecyldimethyl ammonium chloride, and grind vigorously for 10 minutes; Grind for 0.5h.

The above product was put into a vacuum drying oven, and dried in vacuum at 180° C. for 5 h.

The catalyst precursor was taken out and thoroughly ground and dissolved in 100 mL of white oil (lubricating base oil) to obtain an oil-soluble CoMo-based suspension-bed hydrogenation catalyst.

Example 4

A kind of preparation method of oil-soluble NiW base suspension bed hydrogenation catalyst, its preparation method comprises the steps:

Weigh 1.319g of sodium tungstate dihydrate, 0.526g of nickel sulfate hexahydrate, and grind vigorously for 10 minutes; weigh 4.692g of dioctadecyldimethylammonium chloride, and grind vigorously for 10 minutes; Grind for 0.5h.

The above product was put into a vacuum drying oven, and dried in vacuum at 180° C. for 5 h.

The catalyst precursor was taken out and thoroughly ground and dissolved in 100 mL of white oil (lubricating oil base oil) to obtain an oil-soluble NiW-based suspension-bed hydrogenation catalyst.

The oil-soluble catalyst of the present invention can be used in the low-quality heavy oil suspension bed hydrocracking process with high sulfur, high metal and high residual carbon. Its use method is to take a certain volume of the oil-soluble suspension bed hydrogenation catalyst and directly add it to the low-quality heavy oil. The hydrogenation active component is generated in situ by the sulfur-containing compound in the heavy oil, the hydrogenation activity is excellent, and the amount of the catalyst is 50μg/g-2000μg/g calculated as metal. The operating conditions of the suspension bed hydrogenation reactor are: reaction pressure 5MPa-25MPa, reaction temperature 380°C-480°C, volume space velocity 0.2h ^-1 -1.5h ^-1 , hydrogen-oil volume ratio 200-1000.

Take the four oil-soluble suspension-bed hydrogenation catalysts in Examples 1, 2, 3 and 4, and use Qingdao Refinery Vacuum Residue as raw material (see Table 1 for properties), in a high-pressure automatic reactor, the reaction temperature is 430 ℃, the initial pressure of hydrogen is 6MPa, the dosage of catalysts are: 500μg/g (calculated by metal mass) for monometallic catalyst, 300μg/g (calculated by mass of metal of main agent) for bimetallic catalyst, and the reaction time is 1h. Table 2 shows the evaluation results of vacuum residue hydrocracking of different oil-soluble suspension bed hydrogenation catalyst precursors under specified conditions.

Table 1 Properties of the vacuum residue of Qingdao Refining & Chemical Co., Ltd.

Table 2 Evaluation results of vacuum residue hydrocracking

It can be seen from the data in Table 2 that when the reaction temperature is 430°C and the initial hydrogen pressure is 6 MPa, a large amount of small molecule hydrocarbon gas is generated from the vacuum residue without a catalyst, and coke is seriously formed, and the wall phase coke reaches 17.14wt%. After adding an oil-soluble hydrogenation catalyst, the catalyst dissociates hydrogen molecules to generate a large number of hydrogen free radicals, and timely seals the alkyl free radicals generated by thermal cracking, which not only prevents the deep cracking of the alkyl chain, but also prevents the excessive polymerization of macromolecular free radicals, and produces as much as possible Gasoline and diesel fractions, meanwhile, the coke suppression effect is obvious, and the wall phase coke is reduced from 17% to less than 2%. Among them, the Mo-based oil-soluble catalyst has a better coke suppression effect in hydrogenation than the W-based oil-soluble catalyst. It can be seen that the element Mo has a more significant effect on activating hydrogen. After the Mo-based oil-soluble catalyst and CoMo-based oil-soluble catalyst participate in the reaction, there is no wall Phase coke, coke suppression effect is excellent, in line with the continuous start-up requirements of industrial devices; bimetallic oil-soluble hydrogenation catalyst hydrogenation coke suppression effect is stronger than monometallic catalyst, probably because of the synergistic effect between bimetallic, forming CoMoS active phase Or NiWS active phase, so that it can better act as a mediator for combining hydrogen radicals and alkyl radicals.

It can be seen that the oil-soluble suspended bed hydrogenation agent prepared by the present invention has excellent hydrogenation performance, and is especially suitable for the suspension bed hydrogenation process of inferior heavy oil with high sulfur, high metal and high carbon residue. The preparation method of the present invention is extremely simple and practical, has certain universality for the preparation of raw materials, and has great potential for industrial application of catalysts in suspended bed hydrogenation process.

The preparation method of the oil-soluble suspended bed hydrogenation catalyst of the present invention has the following beneficial effects:

(1) The low-temperature solid-phase reaction method is adopted, that is, the reactants are all in the solid phase at room temperature, and there is no solution system involved, which avoids tedious and complicated operations such as filtration and purification. The preparation cost of the catalyst is convenient for low-cost large-scale industrial production.

(2) The oil-soluble suspended bed hydrogenation catalyst prepared by the present invention is dissolved in oil in advance, and directly added to the reaction during the reaction, which can quickly and stably reach molecular level dispersion, thereby reducing the start-up time and catalyst usage.

In the description of this specification, descriptions with reference to the terms "one embodiment", "some embodiments", "example", "specific examples", or "some examples" mean that specific features described in connection with the embodiment or example , structure, material or characteristic is included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the described specific features, structures, materials or characteristics may be combined in any suitable manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine different embodiments or examples and features of different embodiments or examples described in this specification without conflicting with each other.

Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention, those skilled in the art can make the above-mentioned The embodiments are subject to changes, modifications, substitutions and variations.

Claims (6)

1. a preparation method of oil-soluble suspended bed hydrogenation catalyst, is characterized in that, comprises the steps: S101: Mix the main agent metal salt and surfactant evenly, and grind them sufficiently to obtain the mixture; the surfactant is a long-chain alkyl quaternary ammonium salt surfactant; the main agent metal salt is heptamolybdic acid Ammonium, ammonium tetramolybdate, sodium heptamolybdate, ammonium tungstate, ammonium metatungstate and sodium tungstate, or a combination of several; The total charge number of metal ions in the agent metal salt is determined, that is, the total number of negative charges of long-chain alkylammonium ions is consistent with the total number of positive charges of metal ions, so that the final product is electrically neutral; S102: Put the above mixture into a vacuum drying oven, heat and dry to obtain a catalyst precursor; S103: Grinding the above-mentioned catalyst precursor fully, dissolving it in oil, and obtaining a suspension-bed hydrogenation catalyst; The step S101 also includes an auxiliary metal salt, which is uniformly mixed with the main agent metal salt and a surfactant and ground; the auxiliary metal salt is at least cobalt acetate, cobalt carbonate, cobalt nitrate, nickel carbonate and one of nickel nitrate; the metal molar ratio of the metal salt of the main agent and the metal salt of the auxiliary agent is 3:1-1:1; The step S101 includes the following steps: S1011: Fully grind the mixture of the main agent metal salt and the auxiliary agent metal salt for 10min-30min; S1012: Fully grind the long-chain alkyl quaternary ammonium salt surfactant for 10min-30min, and the amount of long-chain alkyl quaternary ammonium salt surfactant is determined according to the total charge of metal ions in the main agent metal salt , that is, the total number of negative charges of long-chain alkylammonium ions is consistent with the total number of positive charges of metal ions, so that the final product is electrically neutral; S1013: Stir and mix the above two evenly, and fully grind for 0.5h-1h; In the step S102, the heating and drying temperature is 60°C-180°C, and the heating and drying time is 1h-5h; In the step S103, the oil product includes at least one of lubricating oil base oil, straight-run diesel oil, catalytically cracked diesel oil, coker diesel oil and liquid wax oil. 2. the preparation method of oil-soluble suspended bed hydrogenation catalyst according to claim 1 is characterized in that, described long-chain alkyl quaternary ammonium salt surfactant comprises at least anionic surfactant, cationic surfactant and amphoteric One or a combination of several ionic surfactants. 3. the preparation method of oil-soluble suspension-bed hydrogenation catalyst according to claim 2 is characterized in that, in described anionic surfactant, the number of carbon atoms of multi-carbon alkyl chain is 5-18, multi-carbon alkyl The number of chains of the chain is 1-4. 4. The preparation method of the oil-soluble suspended bed hydrogenation catalyst according to claim 1, wherein the long-chain alkyl quaternary ammonium salt surfactant is dioctadecyldimethylammonium chloride. 5. The oil-soluble suspended bed hydrogenation catalyst obtained by the method described in any one of claims 1-4. 6. The application of the oil-soluble hydrocracking catalyst according to claim 5 in the suspension bed hydrogenation process.