A method for preparing a low-cost slurry-bed hydrogenation catalyst

Abstract

The application discloses a preparation method of a low-cost slurry bed hydrogenation catalyst, and comprises the following steps: a deactivated residual oil hydrogenation catalyst is subjected to oil removal, crushing and magnetic separation to obtain a low-magnetic catalyst; the low-magnetic catalyst is subjected to acid treatment with oxalic acid and citric acid in sequence and then is calcined to obtain a regenerated catalyst; the regenerated catalyst is impregnated in an impregnation solution to obtain a pre-sulfurized powder catalyst; the pre-sulfurized powder catalyst is mixed with catalytic diesel, a dispersing agent and a stabilizer to obtain the low-cost slurry bed hydrogenation catalyst; and the impregnation solution contains sulfides, inorganic polymerization inhibitors and a treatment solution obtained after citric acid treatment. The method is synergized by the steps of oil removal, magnetic separation, step-by-step acid treatment, calcination, pre-sulfurization and solid dispersion, and finally the obtained solid powder catalyst is used for slurry bed hydrogenation, compared with the prior art, the hydrogenation desulfurization activity of the regenerated catalyst is improved, the coke formation is reduced, and the abrasion of the powder catalyst to the equipment is reduced.

Description

Technical Field

[0001] This invention belongs to the field of slurry bed hydrogenation catalyst technology, specifically relating to a low-cost method for preparing a slurry bed hydrogenation catalyst. Background Technology

[0002] Because heavy oils such as residue contain large amounts of metallic nickel and vanadium, as well as precursors that easily form carbon deposits, residue hydrotreating catalysts are prone to deactivation due to metal deposition and carbon buildup, resulting in a short catalyst lifespan of approximately one year. Deactivated catalysts caused in this way are difficult to regenerate and are generally used only once; deactivated catalysts are typically disposed of through metal recovery. If deactivated residue hydrotreating catalysts could be regenerated and partially or completely replaced with fresh catalysts, it would have significant practical implications for both increasing refinery economic efficiency and reducing environmental pollution.

[0003] Over the years, researchers have developed various methods for regenerating deactivated hydrogenation catalysts. For example, Chinese patent document CN112337501A discloses a method for preparing a sulfide-type regenerated hydrogenation catalyst. This method includes: first, wetting the carbon-deactivated hydrogenation catalyst with an oxygen-containing organic solvent; then, subjecting it to a mild sulfur-burning and carbon-burning treatment; after cooling, vacuum impregnating it with a water-soluble sulfur-containing composite solution; and finally, obtaining a sulfide-type regenerated hydrogenation catalyst after heat treatment. This method can effectively reduce the sulfur-burning and carbon-burning temperature during the regeneration process of the carbon-deactivated hydrogenation catalyst, inhibit the agglomeration of active metals, and weaken the strong interaction between the active metal and the support; simultaneously, it achieves redispersion and sulfidation of the active metal in one step, resulting in a sulfide-type regenerated hydrogenation catalyst with a higher degree of activity recovery. However, this method is only suitable for the regeneration of light oil catalysts (gasoline and diesel hydrogenation catalysts) with a carbon content <5wt% and a harmful metal contaminant (Na+Ca+Fe+V) content <2wt% for carbon-deactivated hydrogenation catalysts, and cannot handle inferior heavy oil hydrogenation catalysts.

[0004] Chinese patent document CN110201694A discloses a method for regenerating a deactivated catalyst in residue oil hydrotreating, comprising the following steps: (1) pre-treating the deactivated catalyst with an organic solvent to remove oil and drying it; (2) treating the deactivated catalyst obtained in step (1) with an acid solution to effectively remove some of the deposited metals in the deactivated catalyst; (3) decarbonizing the deactivated catalyst obtained in step (2); (4) impregnating the deactivated catalyst obtained in step (3) with a metal solution containing one or two Group VIB metal components and one or two Group VIII metal components, and then drying it. This method can effectively remove deposited metals and carbon deposits, restore the pore structure of the catalyst, and effectively improve the activity of the regenerated catalyst. The catalyst regenerated by this method is still a fixed-bed catalyst. Acid treatment will reduce the mechanical strength of the catalyst particles. If it continues to be used in a fixed-bed device, it will cause bed collapse and thus affect the operation cycle of the device. Chinese patent document CN101168137A discloses a regeneration and recovery system for FCC equilibrium catalysts. The system includes: the waste equilibrium catalyst to be treated enters a multi-stage magnetic separation device (A) via a material conveying system; the separated low-magnetic catalyst enters an acidification and demetallization device (B); the high-magnetic catalyst is unloaded and bagged; the slurry treated by the acidification and demetallization device (B) enters an activation device (C), and water and an activator are added to the slurry after the acidification reaction; after a certain reaction time, the slurry is treated by a filtration and dewatering device (D) to form a filter cake; then it enters a drying device (E); the filter cake is calcined in a rotary calcining device (F) to obtain the finished regenerated catalyst, which continuously flows out of the converter, is sieved, and packaged; the entire process is controlled and displayed by an automatic control device (G). However, this method generates a large amount of waste liquid after acid treatment, some of which contains metal ions that are not effectively utilized, and improper waste liquid treatment can cause significant environmental harm.

[0005] Currently, slurry bed catalysts come in three forms: oil-soluble catalysts, water-soluble catalysts, and solid powder catalysts. Oil-soluble and water-soluble catalysts are expensive to prepare, resulting in generally low dosages and thus limited hydrogenation activity. In contrast, solid powder catalysts are inexpensive and can generally be added in larger quantities. However, solid powder catalysts also suffer from poor dispersibility, making them prone to becoming coking centers. Furthermore, the large particles formed by coking can cause wear and tear on equipment, increasing maintenance costs. Summary of the Invention

[0006] To address the problems and areas for improvement in existing technologies, this invention provides a low-cost method for preparing a slurry-bed hydrogenation catalyst. This method utilizes the synergistic effects of steps such as oil removal, magnetic separation, stepwise acid treatment, calcination, presulfurization, and solid dispersion to ultimately regenerate a solid powder catalyst. When used in slurry-bed hydrogenation, this catalyst exhibits superior catalytic performance, is less prone to coking, and reduces wastewater discharge compared to existing technologies.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A method for preparing a low-cost slurry-bed hydrogenation catalyst includes the following steps:

[0009] (1) The deactivated residue hydrotreating catalyst is deoiled, crushed and magnetically separated to obtain a low magnetic agent;

[0010] (2) The low magnetic agent is sequentially acid-treated with oxalic acid and citric acid and then calcined to obtain a regenerated catalyst;

[0011] (3) After impregnating the regenerated catalyst in the impregnation solution, a pre-sulfurized powder catalyst is obtained;

[0012] (4) The pre-sulfurized powder catalyst is mixed evenly with catalytic diesel, dispersant and stabilizer to obtain the low-cost slurry bed hydrogenation catalyst;

[0013] The impregnation solution contains sulfides, inorganic polymerization inhibitors, and a treatment solution obtained after treatment with citric acid.

[0014] Optionally, in step (1) of the preparation method of the low-cost slurry-bed hydrogenation catalyst provided by the present invention, the oil removal step can be carried out using conventional industry practices, such as roasting or organic solvent degreasing. The present invention recommends the organic solvent degreasing method, such as placing the deactivated residue hydrogenation catalyst in an organic solvent and treating it at 60-150°C for 1-10 hours. In this way, the oily substances in the deactivated residue hydrogenation catalyst will dissolve in the organic solvent and then separate from the catalyst. The specific amount and type of organic solvent are not limited, as long as they can dissolve the oily substances in the catalyst. The specific amount can be adjusted according to the actual situation. The mass-volume ratio of the deactivated residue hydrogenation catalyst to the organic solvent recommended by the present invention is 1g:(1-8)ml. The organic solvent can be selected from one or more of petroleum ether, naphtha, kerosene, toluene, etc.

[0015] Optionally, in step (1) of the preparation method of the low-cost slurry bed hydrogenation catalyst provided by the present invention, the particle size of the deactivated residue hydrogenation catalyst after pulverization and deoiling is 20-200 micrometers, preferably 40-100 micrometers.

[0016] Optionally, in step (1) of the preparation method of the low-cost slurry-bed hydrotreating catalyst provided by the present invention, the magnetic separation recommended by the present invention is carried out in a roller magnetic separator. The feed rate of the pulverized deactivated residue hydrotreating catalyst is 50-100 kg / h, preferably 60-80 kg / h; the rotation speed of the magnetic roller is 100-500 r / min, preferably 200-400 r / min. The magnetic separation yields high-magnetic-content and low-magnetic-content catalysts, wherein the high-magnetic-content catalyst (deactivated catalyst with high heavy metal content) is discharged to the waste catalyst tank, and the low-magnetic-content catalyst (deactivated catalyst with low heavy metal content) is discharged to the recovery catalyst tank. Based on the total weight of the deactivated residue hydrotreating catalyst entering the roller magnetic separator as 100%, the weight yield of the low-magnetic-content catalyst is 50%-90%, preferably 70%-90%.

[0017] Optionally, in step (2) of the preparation method of the low-cost slurry-bed hydrogenation catalyst provided by the present invention, vanadium in the low-magnetic agent is first removed by utilizing the high selectivity of oxalic acid for vanadium, and then nickel in the low-magnetic agent is removed by utilizing the high selectivity of citric acid for nickel. The present invention recommends sequential leaching with oxalic acid solution and citric acid solution, wherein the mass concentration of the oxalic acid solution is 1%–10%, preferably 5%–8%; the leaching temperature is 10–100°C; and the leaching time is 1–6 h; the mass concentration of the citric acid solution is 10%–20%, preferably 14%–18%; the leaching temperature is 10–100°C; and the leaching time is 1–6 h. More preferably, when using oxalic acid solution for leaching, an excess impregnation method is used; when using citric acid solution for leaching, an equal-volume impregnation method is used.

[0018] Optionally, in step (2) of the preparation method of the low-cost slurry bed hydrogenation catalyst provided by the present invention, the calcination is carried out in an air atmosphere, first at 200-400°C for 1-4 hours, and then at 400-600°C for 2-6 hours.

[0019] Optionally, in step (3) of the preparation method of the low-cost slurry bed hydrogenation catalyst provided by the present invention, the treatment liquid obtained after citric acid treatment contains metallic nickel and citric acid. Metallic nickel is a hydrogenation active component, while citric acid is a good complexing agent. The treatment liquid of citric acid is reused to reduce the cost of waste liquid treatment and the cost of catalyst regeneration.

[0020] Optionally, in the preparation method of the low-cost slurry bed hydrogenation catalyst provided by the present invention, the sulfide is selected from one or more of thiols, thiophenols, thioethers, and disulfides;

[0021] The mass ratio of the regenerated catalyst to the sulfide is 20:1 to 4, preferably 20:1 to 2.

[0022] Optionally, in step (3) of the method for preparing the low-cost slurry bed hydrogenation catalyst provided by the present invention, the impregnation is an equal-volume impregnation.

[0023] Optionally, in the preparation method of the above-mentioned low-cost slurry bed hydrogenation catalyst provided by the present invention, the inorganic polymerization inhibitor is selected from one or more of ferric chloride, cuprous chloride, copper sulfate, titanium trichloride, sodium sulfate and ammonium thiocyanate;

[0024] The mass ratio of the regenerated catalyst to the inorganic polymerization inhibitor is 100:0.1 to 1.5.

[0025] Optionally, in step (3) of the above-mentioned low-cost slurry bed hydrogenation catalyst preparation method provided by the present invention, after impregnation, there is a drying step. Preferably, the drying is carried out in a nitrogen atmosphere, and the drying temperature is 150-300°C for 8-24 hours.

[0026] Optionally, in step (4) of the method for preparing the low-cost slurry-bed hydrotreating catalyst provided by the present invention, the mass ratio of the pre-sulfurized powder catalyst to the catalytic diesel is 1:2 to 10; preferably 1:2 to 5. Because the catalytic diesel contains a large amount of aromatics, it easily combines with the asphaltenes in heavy oil, thereby promoting its phase stability; using it as a continuous phase makes the final slurry-bed hydrotreating catalyst more stable and its dispersion in the slurry-bed reactor better, thus reducing the coking rate. Using other diesel fuels reduces the dispersion of the hydrotreating catalyst in the slurry-bed reactor, resulting in a high coking rate.

[0027] Optionally, in step (4) of the method for preparing the low-cost slurry bed hydrogenation catalyst provided by the present invention, the dispersant is selected from one or more of polyoxyethylene ether, polyoxypropylene ether, ethylene oxide and propylene oxide;

[0028] The mass ratio of the pre-sulfurized powder catalyst to the dispersant is 100:0.5 to 5; preferably 100:1 to 2.

[0029] Optionally, in step (4) of the method for preparing the low-cost slurry bed hydrogenation catalyst provided by the present invention, the stabilizer is selected from one or more of methylcellulose, sodium carboxymethylcellulose and hydroxypropylcellulose;

[0030] The mass ratio of the pre-vulcanized powder catalyst to the stabilizer is 100:0.1 to 1.0; preferably 100:0.5 to 0.8.

[0031] Optionally, in the preparation method of the low-cost slurry bed hydrogenation catalyst provided by the present invention, in step (4), the mixing is stirred mixing, and the mixing temperature is 50-100℃.

[0032] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0033] 1. The low-cost slurry-bed hydrotreating catalyst preparation method provided by this invention first removes oily substances from the deactivated catalyst through deoiling, improving the subsequent use of magnetic separation to separate catalysts with excessively high metal content that have essentially lost their regeneration value (high magnetic agent); this reduces regeneration costs while improving resource utilization. Then, oxalic acid's high selectivity for vanadium is used to leach the vanadium from the catalyst (allowing for recycling), followed by citric acid leaching of nickel, effectively removing nickel and vanadium deposited on the catalyst that affect its activity. Next, calcination restores the catalyst's pore structure. Combined with pre-sulfurization modification and the addition of inorganic polymerization inhibitors and solid dispersion to the pre-sulfurization impregnation solution, the deactivated residue hydrotreating catalyst is treated to improve the hydrodesulfurization activity of the regenerated catalyst and reduce coking, thus reducing wear on equipment caused by powdered catalysts. Furthermore, the slurry-bed hydrotreating catalyst prepared by this method directly avoids the disadvantage of reduced catalyst strength caused by acid treatment. This method fully utilizes the deactivated residue hydrotreating catalyst, aligning with the concept of green and environmentally friendly development; and significantly reduces the usage cost of slurry-bed hydrotreating catalysts.

[0034] 2. In the preparation method of the low-cost slurry-bed hydrogenation catalyst provided by the present invention, the treatment liquid obtained after citric acid treatment in step (2) is further introduced into the impregnation liquid in step (3), and mixed with sulfides and inorganic polymerization inhibitors to obtain the impregnation liquid. Combined with other steps, the anti-coking performance and catalytic activity of the catalyst can be significantly improved, while the hazardous waste emission is greatly reduced. Specifically, the impregnation liquid contains the complexing agent citric acid, which can react and dissolve with the metal oxides formed during the regeneration process, promoting the full dispersion of the metal oxides. It further contacts the sulfides in the impregnation liquid to form sulfur-containing metal complexes. Under nitrogen heating conditions, the sulfur-containing metal complexes decompose in situ to generate active metal sulfides, realizing the dispersion, reactivation and sulfidation of metals in the regenerated catalyst in one step. At the same time, the nickel ions introduced by the treatment liquid obtained after citric acid treatment in the impregnation liquid can replenish some of the active metals lost during the operation and regeneration of the catalyst, improving the dispersion and effective utilization rate of the active components. Inorganic polymerization inhibitors can reduce the formation of large molecules by free radical polymerization during thermal cracking, thereby reducing coking on the catalyst surface, preventing catalyst particles from agglomerating into large coking particles, and thus preventing large insoluble molecules in the product oil from clogging equipment or causing wear to the equipment.

[0035] 3. Catalytic diesel is rich in aromatics and has a high viscosity, making it an ideal oily dispersed phase. When catalyst powder, dispersant, and stabilizer are added to it, the catalyst powder can form a relatively stable suspension system with catalytic diesel under the synergistic effect of surfactant. Adding this type of dispersed catalyst to the reactor can result in a higher degree of catalyst dispersion, faster mixing speed, reduced catalyst dispersion time, and increased reactor space velocity. Detailed Implementation

[0036] The present invention will now be described in detail through embodiments. It should be noted that the following embodiments are only for further illustration of the present invention and should not be construed as limiting the scope of protection of the present invention. Those skilled in the art can make some non-essential improvements and adjustments to the present invention based on the above description.

[0037] Example 1

[0038] This embodiment provides a method for preparing a low-cost slurry-bed hydrogenation catalyst, comprising the following steps:

[0039] (1) Take 100g of deactivated residue hydrotreating catalyst A after the industrial unit has been running, put it into a Soxhlet extractor, add 500mL of petroleum ether, treat at 100℃ for 6 hours, dry, and then pulverize. Control the particle size to 63-90 micrometers using a standard sieve. Separate the pulverized catalyst through a roller magnetic separator with a feed rate of 60kg / h and a magnetic roller speed of 300r / min. Obtain 75g of low magnetic agent (low metal content catalyst) (based on the total weight of deactivated residue hydrotreating catalyst A entering the roller magnetic separator as 100%, the weight yield of low magnetic agent is 75%).

[0040] (2) The above-mentioned low magnetic agent was first impregnated with an 8% oxalic acid solution at 60°C for 2 hours in excess; then impregnated with a 15% citric acid solution at 80°C in an equal volume for 4 hours. The impregnated catalyst was calcined at 300°C in air for 2 hours, and then calcined at 450°C for 4 hours to obtain the regenerated catalyst;

[0041] (3) The citric acid extract obtained in step (2), ethanethiol and ferric chloride are mixed to prepare an impregnation solution, and then the above-mentioned regenerated catalyst is added for impregnation in equal volume. The mass ratio of the regenerated catalyst, ethanethiol and ferric chloride is 100:10:1. Then, the solution is dried at 200°C for 16 hours in a nitrogen atmosphere to obtain a pre-sulfurized powder catalyst.

[0042] (4) The above-mentioned pre-sulfurized powder catalyst and catalytic diesel are stirred and mixed at a mass ratio of 1:5 and the mixing temperature is 50°C. Then, polyoxypropylene ether and methylcellulose are added, wherein the mass ratio of pre-sulfurized powder catalyst, polyoxypropylene ether and methylcellulose is 100:2:0.5, and finally a slurry bed hydrogenation catalyst is obtained.

[0043] Example 2

[0044] This embodiment provides a method for preparing a low-cost slurry-bed hydrogenation catalyst, comprising the following steps:

[0045] (1) Take 100g of deactivated residue hydrotreating catalyst A after the industrial unit has been running, put it into a Soxhlet extractor, add 100mL of petroleum ether, treat at 60℃ for 10 hours, dry, and then pulverize. Control the particle size to be 20-58 micrometers using a standard sieve. Separate the pulverized catalyst through a roller magnetic separator with a feed rate of 50kg / h and a magnetic roller speed of 100r / min to obtain 50g of low magnetic agent (low metal content catalyst) (based on the total weight of deactivated residue hydrotreating catalyst A entering the roller magnetic separator as 100%, the weight yield of low magnetic agent is 50%).

[0046] (2) The above-mentioned low magnetic agent was first impregnated with an excess of 10% oxalic acid solution at 100°C for 1 hour; then impregnated with an equal volume of 20% citric acid solution at 100°C for 1 hour. The impregnated catalyst was calcined at 200°C for 4 hours in air atmosphere, and then calcined at 400°C for 4 hours to obtain the regenerated catalyst;

[0047] (3) The citric acid extract obtained in step (2), ethanethiol and ferric chloride are mixed to prepare an impregnation solution, and then the above-mentioned regenerated catalyst is added for impregnation in equal volume. The mass ratio of the regenerated catalyst, ethanethiol and ferric chloride is 100:20:1.5. Then, the solution is dried at 150°C for 24 hours in a nitrogen atmosphere to obtain a pre-sulfurized powder catalyst.

[0048] (4) The above-mentioned pre-sulfurized powder catalyst and catalytic diesel are stirred and mixed at a mass ratio of 1:2 and the mixing temperature is 80°C. Then, polyoxypropylene ether and methylcellulose are added. The mass ratio of pre-sulfurized powder catalyst, polyoxypropylene ether and methylcellulose is 100:5:1. Finally, a slurry bed hydrogenation catalyst is obtained.

[0049] Example 3

[0050] This embodiment provides a method for preparing a low-cost slurry-bed hydrogenation catalyst, comprising the following steps:

[0051] (1) Take 100g of deactivated residue hydrotreating catalyst A after the industrial unit has been running, put it into a Soxhlet extractor, add 800mL of petroleum ether, treat at 150℃ for 1 hour, dry, and then pulverize. Control the particle size to be 150-200 micrometers using a standard sieve. Separate the pulverized catalyst through a roller magnetic separator with a feed rate of 100kg / h and a magnetic roller speed of 500r / min to obtain 90g of low magnetic agent (low metal content catalyst) (based on the total weight of deactivated residue hydrotreating catalyst A entering the roller magnetic separator as 100%, the weight yield of low magnetic agent is 90%).

[0052] (2) The above-mentioned low magnetic agent was first impregnated with an excess of 1% oxalic acid solution at 10°C for 6 hours; then impregnated with an equal volume of 10% citric acid solution at 10°C for 6 hours. The impregnated catalyst was calcined at 400°C for 1 hour in air atmosphere, and then calcined at 600°C for 2 hours to obtain the regenerated catalyst;

[0053] (3) The citric acid extract obtained in step (2), ethanethiol and ferric chloride are mixed to prepare an impregnation solution, and then the above-mentioned regenerated catalyst is added for impregnation in equal volume. The mass ratio of the regenerated catalyst, ethanethiol and ferric chloride is 100:5:0.5. Then, the solution is dried at 300°C for 8 hours in a nitrogen atmosphere to obtain a pre-sulfurized powder catalyst.

[0054] (4) The above-mentioned pre-sulfurized powder catalyst and catalytic diesel are stirred and mixed at a mass ratio of 1:10 and the mixing temperature is 100°C. Then, polyoxypropylene ether and methylcellulose are added, wherein the mass ratio of pre-sulfurized powder catalyst, polyoxypropylene ether and methylcellulose is 100:0.5:0.1, and finally a slurry bed hydrogenation catalyst is obtained.

[0055] Example 4

[0056] This embodiment provides a method for preparing a low-cost slurry-bed hydrogenation catalyst, comprising the following steps:

[0057] (1) Take 100g of deactivated residue hydrotreating catalyst A after the industrial unit has been running, put it into a Soxhlet extractor, add 500mL of toluene, treat at 100℃ for 6 hours, dry, and then pulverize. Control the particle size to be 90-150 micrometers using a standard sieve. Separate the pulverized catalyst through a roller magnetic separator with a feed rate of 70kg / h and a magnetic roller speed of 200r / min. Obtain 80g of low magnetic agent (low metal content catalyst) (based on the total weight of deactivated residue hydrotreating catalyst A entering the roller magnetic separator as 100%, the weight yield of low magnetic agent is 80%).

[0058] (2) The above-mentioned low magnetic agent was first impregnated with an excess of 5% oxalic acid solution at 50°C for 3 hours; then impregnated with an equal volume of 14% citric acid solution at 60°C for 5 hours. The impregnated catalyst was calcined at 300°C in air for 2 hours, and then calcined at 450°C for 4 hours to obtain the regenerated catalyst;

[0059] (3) The citric acid extract obtained in step (2), thiophenol, and inorganic polymerization inhibitor (copper sulfate and sodium sulfate mixed in a mass ratio of 1:1) are mixed to prepare an impregnation solution, and then the above-mentioned regenerated catalyst is added for equal-volume impregnation. The mass ratio of the regenerated catalyst, thiophenol, and inorganic polymerization inhibitor is 100:5:0.5. Then, the solution is dried at 200°C for 16 hours in a nitrogen atmosphere to obtain a pre-sulfurized powder catalyst.

[0060] (4) The above-mentioned pre-sulfurized powder catalyst and catalytic diesel are stirred and mixed at a mass ratio of 1:3 and the mixing temperature is 50°C. Then, polyoxyethylene ether and sodium carboxymethyl cellulose are added. The mass ratio of pre-sulfurized powder catalyst, polyoxyethylene ether and sodium carboxymethyl cellulose is 100:1:0.7. Finally, a slurry bed hydrogenation catalyst is obtained.

[0061] Example 5

[0062] This embodiment provides a method for preparing a low-cost slurry-bed hydrogenation catalyst, comprising the following steps:

[0063] (1) Take 100g of deactivated residue hydrotreating catalyst A after the industrial unit has been running, put it into a Soxhlet extractor, add 500mL of petroleum ether, treat at 100℃ for 6 hours, dry, and then pulverize. Control the particle size to 63-90 micrometers using a standard sieve. Separate the pulverized catalyst through a roller magnetic separator with a feed rate of 80kg / h and a magnetic roller speed of 400r / min. Obtain 85g of low magnetic agent (low metal content catalyst) (based on the total weight of deactivated residue hydrotreating catalyst A entering the roller magnetic separator as 100%, the weight yield of low magnetic agent is 85%).

[0064] (2) The above-mentioned low magnetic agent was first impregnated with an excess of 7% oxalic acid solution at 70°C for 2 hours; then impregnated with an equal volume of 15% citric acid solution at 100°C for 4 hours. The impregnated catalyst was calcined at 300°C in air for 2 hours, and then calcined at 500°C for 5 hours to obtain the regenerated catalyst;

[0065] (3) The citric acid leaching solution obtained in step (2), the sulfiding agent (a mixture of dimethyl sulfide and dimethyl disulfide in a mass ratio of 1:1), and cuprous chloride are mixed to prepare an impregnation solution. Then, the above-mentioned regenerated catalyst is added for impregnation in equal volumes. The mass ratio of the regenerated catalyst, the sulfiding agent, and the cuprous chloride is 100:10:0.1. The solution is then dried at 200°C for 16 hours in a nitrogen atmosphere to obtain a pre-sulfidated powder catalyst.

[0066] (4) The above-mentioned pre-sulfurized powder catalyst and catalytic diesel are stirred and mixed at a mass ratio of 1:4 and the mixing temperature is 50°C. Then, a dispersant (ethylene oxide and propylene oxide are mixed at a mass ratio of 1:1) and a stabilizer (sodium carboxymethyl cellulose and hydroxypropyl cellulose are mixed at a mass ratio of 1:1) are added. The mass ratio of the pre-sulfurized powder catalyst, dispersant and stabilizer is 100:1.5:0.8. Finally, a slurry bed hydrogenation catalyst is obtained.

[0067] Comparative Example 1

[0068] The preparation method of the slurry-bed hydrogenation catalyst provided in this comparative example is similar to that in Example 1, except that the magnetic separation step is omitted in step (1) of this comparative example. The specific preparation method of the slurry-bed hydrogenation catalyst provided in this comparative example is as follows:

[0069] (1) Take 100g of deactivated residue hydrogenation catalyst A after the industrial unit has been running, put it into a Soxhlet extractor, add 500mL of petroleum ether, treat at 100℃ for 6 hours, dry, then crush, and control its particle size to 63-90 micrometers with a standard sieve to obtain the crushed catalyst.

[0070] (2) The above-mentioned pulverized catalyst was first impregnated with an 8% oxalic acid solution at 60°C for 2 hours in excess; then impregnated with a 15% citric acid solution at 80°C in an equal volume for 4 hours. The impregnated catalyst was calcined at 300°C in air for 2 hours, and then calcined at 450°C for 4 hours to obtain a regenerated catalyst;

[0071] (3) The citric acid extract obtained in step (2), ethanethiol and ferric chloride are mixed to prepare an impregnation solution, and then the above-mentioned regenerated catalyst is added for impregnation in equal volume. The mass ratio of the regenerated catalyst, ethanethiol and ferric chloride is 100:10:1. Then, the solution is dried at 200°C for 16 hours in a nitrogen atmosphere to obtain a pre-sulfurized powder catalyst.

[0072] (4) The above-mentioned pre-sulfurized powder catalyst and catalytic diesel are stirred and mixed at a mass ratio of 1:5 and the mixing temperature is 50°C. Then, polyoxypropylene ether and methylcellulose are added, wherein the mass ratio of pre-sulfurized powder catalyst, polyoxypropylene ether and methylcellulose is 100:2:0.5, and finally slurry bed hydrogenation catalyst B1 is obtained.

[0073] Comparative Example 2

[0074] The preparation method of the slurry bed hydrogenation catalyst provided in this comparative example is similar to that in Example 1, except that in step (2) of this comparative example, oxalic acid and citric acid are mixed and then subjected to acid treatment together. The specific preparation method of the slurry bed hydrogenation catalyst provided in this comparative example is as follows:

[0075] (1) Take 100g of deactivated residue hydrotreating catalyst A after the industrial unit has been running, put it into a Soxhlet extractor, add 500mL of petroleum ether, treat at 100℃ for 6 hours, dry, and then pulverize. Control the particle size to 63-90 micrometers using a standard sieve. Separate the pulverized catalyst through a roller magnetic separator with a feed rate of 60kg / h and a magnetic roller speed of 300r / min. Obtain 75g of low magnetic agent (low metal content catalyst) (based on the total weight of deactivated residue hydrotreating catalyst A entering the roller magnetic separator as 100%, the weight yield of low magnetic agent is 75%).

[0076] (2) The above low magnetic agent was placed in a mixed acid solution with oxalic acid mass concentration of 8% and citric acid mass concentration of 15%, and impregnated at 60°C for 4 hours; the impregnated catalyst was calcined at 300°C for 2 hours in air atmosphere, and then calcined at 450°C for 4 hours to obtain the regenerated catalyst.

[0077] (3) The leaching solution from step (2), ethanethiol, and ferric chloride are mixed to prepare an impregnation solution, and then the above-mentioned regenerated catalyst is added for impregnation in equal volumes. The mass ratio of the regenerated catalyst, ethanethiol, and ferric chloride is 100:10:1. The solution is then dried at 200°C for 16 hours in a nitrogen atmosphere to obtain a pre-sulfurized powder catalyst.

[0078] (4) The above-mentioned pre-sulfurized powder catalyst and catalytic diesel are stirred and mixed at a mass ratio of 1:5 and the mixing temperature is 50°C. Then, polyoxypropylene ether and methylcellulose are added, wherein the mass ratio of pre-sulfurized powder catalyst, polyoxypropylene ether and methylcellulose is 100:2:0.5, and finally slurry bed hydrogenation catalyst B2 is obtained.

[0079] Comparative Example 3

[0080] The preparation method of the slurry bed hydrogenation catalyst provided in this comparative example is similar to that in Example 1, except that the impregnation solution in step (3) of this comparative example does not contain the sulfiding agent ethyl mercaptan, and finally catalyst B3 is obtained.

[0081] Comparative Example 4

[0082] The preparation method of the slurry bed hydrogenation catalyst provided in this comparative example is similar to that in Example 1, except that the inorganic polymerization inhibitor ferric chloride was not added to the impregnation solution in step (3) of this comparative example, and catalyst B4 was finally obtained.

[0083] Comparative Example 5

[0084] The preparation method of the slurry bed hydrogenation catalyst provided in this comparative example is similar to that in Example 1, except that step (4) is omitted in this comparative example, and catalyst B5 is finally obtained.

[0085] Experimental Example

[0086] Using atmospheric residue oil as feedstock, the hydrodesulfurization of the slurry bed hydrotreating catalyst was evaluated in a high-pressure autoclave. The operating conditions were: temperature 430℃, pressure 16 MPa, hydrogen-to-oil ratio 1200, feedstock oil 150g, and catalyst powder 3g. The desulfurization rate was then calculated.

[0087] Desulfurization rate = (Sulfur content of raw material - Sulfur content of product) / Sulfur content of raw material

[0088] Relative desulfurization rate = Reference agent (deactivated or regenerated catalyst) / Fresh agent desulfurization rate

[0089] Coke yield = (mass of toluene-insoluble matter in the product obtained from hydrodesulfurization - amount of catalyst added) / amount of oil added

[0090] The coke particle size was obtained by statistically averaging microscopic images (200x).

[0091] The specific surface area was tested according to GB / T 38691-2020, the pore volume was tested according to GB / T 21650-2018, and the Ni and V contents were measured by ICP spectroscopy. The specific catalyst properties and reaction results are shown in the table below.

[0092] Table 1

[0093]

[0094] Note: The desulfurization rate of fresh agent A is used as the benchmark, therefore the relative desulfurization rate of fresh agent A is 100%.

[0095] As can be seen from the comparison between Example 1 and Comparative Example 1, without magnetic separation, catalysts with high metal content cannot be separated. Therefore, the Ni and V contents in Example 1 are lower than those in Comparative Example 1, and the desulfurization activity of Example 1 is significantly higher than that of Comparative Example 1. This is because some Ni and V in the catalyst with high metal content still exist in the form of metal porphyrin, which blocks some catalyst channels and affects the catalytic performance of the catalyst.

[0096] As can be seen from the comparison between Example 1 and Comparative Example 2, when stepwise acid treatment is not performed, the Ni ions in the leaching solution cannot be further utilized. Therefore, the active metal Ni content in Comparative Example 2 is significantly lower than that in Example 1, and its desulfurization activity is also lower than that in Example 1.

[0097] A comparison of Example 1 and Comparative Example 3 shows that the catalyst properties are basically the same, but the desulfurization activity of Comparative Example 3 is lower than that of Example 1. The reason is that no sulfiding agent was added, and its catalyst form is still in the oxidized state, resulting in lower desulfurization activity. During the reaction, the catalyst first undergoes a sulfidation reaction in the high-pressure reactor to obtain higher desulfurization activity, which causes its desulfurization activity to be lower than that of the sulfidation catalyst in a shorter reaction time.

[0098] As can be seen from the comparison between Example 1 and Comparative Example 4, the coking rate and coking particle size of Comparative Example 4 are significantly increased. This is because there is no polymerization inhibition performance, the catalyst becomes the coking center, the amount of coking increases, and some catalyst particles agglomerate into larger particles.

[0099] As can be seen from the comparison between Example 1 and Comparative Example 5, the powdered catalyst that has not undergone dispersion treatment requires a longer reaction time to achieve the same desulfurization effect. This is because the solid powdered catalyst has poor dispersibility, a slower mixing time, and poor dispersion properties also lead to a slight increase in coking rate and coking particles.

[0100] Of course, the present invention may have other various embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding changes and modifications should all fall within the protection scope of the claims of the present invention.

Claims

1. A method for preparing a low-cost slurry-bed hydrogenation catalyst, characterized in that, Includes the following steps: (1) The deactivated residue hydrotreating catalyst is deoiled, crushed and magnetically separated to obtain a low magnetic agent; (2) The low magnetic agent is subjected to acid treatment with oxalic acid and citric acid in sequence and then calcined to obtain a regenerated catalyst; (3) After impregnating the regenerated catalyst in the impregnation solution, a pre-sulfurized powder catalyst is obtained; (4) The pre-sulfurized powder catalyst is mixed evenly with catalytic diesel, dispersant and stabilizer to obtain the low-cost slurry bed hydrogenation catalyst; The impregnation solution contains sulfides, inorganic polymerization inhibitors, and a treatment solution obtained after citric acid treatment. The sulfide is selected from one or more of thiols, thiophenols, and thioethers.

2. The preparation method according to claim 1, characterized in that, After pulverization, the particle size of the deactivated residue hydrotreating catalyst is 20-200 micrometers.

3. The preparation method according to claim 1, characterized in that, The magnetic separation adopts roller magnetic separation, and the rotation speed of the magnetic roller is 100~500 r / min.

4. The preparation method according to claim 1, characterized in that, The calcination is carried out in an air atmosphere, first at 200-400°C for 1-4 hours, and then at 400-600°C for 2-6 hours.

5. The preparation method according to claim 1, characterized in that, The mass ratio of the regenerated catalyst to the sulfide is 20:1~4.

6. The preparation method according to claim 1, characterized in that, The inorganic polymerization inhibitor is selected from one or more of ferric chloride, cuprous chloride, copper sulfate, titanium trichloride, sodium sulfate, and ammonium thiocyanate. The mass ratio of the regenerated catalyst to the inorganic polymerization inhibitor is 100:0.1~1.

5.

7. The preparation method according to claim 1, characterized in that, The mass ratio of the pre-sulfurized powder catalyst to the catalytic diesel is 1:2~10.

8. The preparation method according to claim 1, characterized in that, The dispersant is selected from one or more of polyoxyethylene ether, polyoxypropylene ether, ethylene oxide, and propylene oxide; The mass ratio of the pre-vulcanized powder catalyst to the dispersant is 100:0.5~5.

9. The preparation method according to claim 1, characterized in that, The stabilizer is selected from one or more of methylcellulose, sodium carboxymethylcellulose, and hydroxypropylcellulose; The mass ratio of the pre-vulcanized powder catalyst to the stabilizer is 100:0.1~1.

0.

10. The preparation method according to claim 1, characterized in that, In step (4), the mixing temperature is 50~100℃.

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