Preparation method and application of regenerated slurry bed hydrogenation catalyst

Abstract

The present invention relates to the field of petrochemicals, and discloses a preparation method and application of a regenerated slurry bed hydrogenation catalyst. The preparation method comprises the following steps: 1) calcining, pulverizing, and sieving a waste fixed bed hydrogenation catalyst to obtain particles; 2) adding iron powder to the particles and mixing them evenly; 3) impregnating the product obtained in step 2) with a thiol polyoxyethylene ether surfactant solution, drying, and cooling to obtain a regenerated slurry bed hydrogenation catalyst. The present invention uses a waste fixed bed hydrogenation catalyst as a main component and iron powder as an auxiliary component. The obtained catalyst not only has excellent hydrogenation activity, but also has the advantages of simple process, low cost, low carbon, and environmental protection. By using the regenerated slurry bed hydrogenation catalyst and the slurry bed hydrogenation process of the present invention to treat low-quality heavy oil, low-value-added low-quality heavy oil can be converted into combustible gas, feed for a fixed bed hydrogenation unit, etc., and ultimately into a clean fuel product, which can significantly improve economic efficiency.

Description

Technical Field

[0001] The present invention relates to the field of petrochemicals, and in particular to a preparation method of a regenerated slurry bed hydrogenation catalyst and application thereof. Background Art

[0002] The three main technologies for hydroprocessing low-quality heavy oils are fixed-bed hydrogenation, ebullating-bed hydrogenation, and slurry-bed hydrogenation, ranked by process advancement, specifically the degree of feedstock degradation. Fixed-bed hydrogenation can only process feedstocks with a metal (Ni+V) content of less than 200 μg / g and an asphaltene content of less than 1%. Slurry-bed hydrogenation is currently capable of processing even lower-quality feedstocks, while ebullating-bed hydrogenation processes typically handle feedstocks with a degradation level somewhere between the two. Low-quality heavy oils such as vacuum residue, ethylene tar, and catalytic slurry oil, which have asphaltene contents exceeding 5%, are currently unsuitable for both fixed-bed and ebullating-bed hydrogenation technologies. Industrially, my country has the largest number of fixed-bed hydrogenation units, while ebullating-bed and slurry-bed units are relatively rare. Slurry-bed hydrogenation, due to its ability to process even lower-quality feedstocks, high conversion rates, high clean fuel yields, long operating cycles, and superior product quality, is poised to become the primary method for processing low-quality heavy oils in the future.

[0003] Among existing slurry bed hydrogenation catalysts, the one disclosed in Chinese patent CN104826662A uses an iron-based FeOOH catalyst as the main catalyst, molybdenum as the auxiliary agent, and dry coal powder and activated carbon powder as the carrier. The one disclosed in Chinese patent CN106622268B uses silica-alumina and alumina as the carrier, with iron, calcium, and molybdenum as the active metals, with the oxide content ranging from 10-40% by mass. The one disclosed in Chinese patent CN104907078B uses molybdenum-containing red mud or hematite powder as the main catalyst, with activated carbon as the carrier. The one disclosed in Chinese patent CN113145106 uses a transition metal tungsten catalyst supported on carbonaceous particles. However, all of these catalysts require a certain amount of additional active metal to achieve their catalytic effect, resulting in high catalyst processing costs.

[0004] Currently, the main methods for reusing these spent hydrogenation catalysts include: 1. Regeneration and reprocessing for reuse as fixed-bed hydrogenation catalysts; 2. Metal component recovery; and 3. Landfill disposal. Most metal component recovery methods suffer from lengthy processing steps, low waste hydrogenation catalyst utilization rates, and poor overall economic efficiency. Landfill disposal is becoming increasingly unfeasible due to increasing costs and environmental risks. Therefore, developing a simple, low-cost, environmentally friendly, and efficient method for regenerating spent hydrogenation catalysts is of great importance. Summary of the Invention

[0005] In order to solve the above technical problems, the present invention provides a preparation method and application of a regenerated slurry bed hydrogenation catalyst. The present invention uses an environmentally harmful abandoned fixed bed hydrogenation catalyst as a main component and low-cost iron powder as an auxiliary component, and applies it as a slurry bed hydrogenation catalyst to the hydrogenation processing of inferior heavy oil. It not only has excellent hydrogenation activity, but also has the advantages of simple process, low cost, low carbon and environmental protection. The regenerated slurry bed hydrogenation catalyst and slurry bed hydrogenation process of the present invention are used to treat inferior heavy oil, which can convert low-value-added inferior heavy oil into combustible gas, feed for fixed bed hydrogenation equipment, etc., and finally into clean fuel products, which can significantly improve economic efficiency.

[0006] The specific technical solutions of the present invention are:

[0007] In a first aspect, the present invention provides a method for preparing a regenerated slurry bed hydrogenation catalyst, comprising the following steps:

[0008] 1) The spent fixed-bed hydrogenation catalyst is burned, pulverized, and sieved to obtain particles with a particle size of 50-90 μm.

[0009] 2) Add iron powder with a particle size of 50-75 μm and a particle size dispersion of less than 10% to the particles in step 1) at a mass ratio of 1-4:100 and mix evenly.

[0010] 3) impregnating the product obtained in step 2) with 4-10 wt % of a mercaptan polyoxyethylene ether surfactant solution at a volume ratio of 1-3:1, drying, and cooling to obtain a regenerated slurry bed hydrogenation catalyst with a particle size of 60-100 μm.

[0011] The regenerated slurry bed hydrogenation catalyst of the present invention uses environmentally harmful abandoned fixed bed hydrogenation catalyst as the main component and low-cost iron powder as the auxiliary component. It can effectively utilize the hydrogenation activity of the original metal components (W, Mo, Ni, etc.) of the abandoned fixed bed hydrogenation catalyst itself, and work synergistically with iron to use it as a slurry bed hydrogenation catalyst for the hydrogenation processing of inferior heavy oil. It not only has excellent hydrogenation activity, but also has the advantages of turning waste into treasure, making full use of resources, and being low-carbon and environmentally friendly. It should be emphasized that the regenerated slurry bed hydrogenation catalyst of this application has the following key points during the preparation process:

[0012] First, in terms of particle size: the method of the present invention removes carbon deposits, impurities, and dirty oil on the inner and outer surfaces of the spent fixed-bed hydrogenation catalyst by high-temperature calcination, thereby obtaining particles of suitable particle size, which have more active sites than their original form, and at the same time optimizes the particle size of the iron powder, so that the regenerated slurry bed hydrogenation catalyst has better activity and richer internal and external surface areas and pores. For the macromolecular asphalt and colloid in the low-quality heavy oil that affect the operating life of the downstream fixed-bed hydrogenation unit, whether based on the macromolecular deposition mechanism or the hydrogenation conversion mechanism, they can be removed by deposition and / or hydrogenation conversion methods, thereby achieving a higher liquid phase product yield and a lower gas phase product yield (liquid phase product has a higher added value) than the existing slurry bed catalyst, and optimizing the product distribution. If the particle size is too large, it is not conducive to the combination of the catalyst and the oil phase reactants, the catalyst has fewer active sites, and the reaction is incomplete; at the same time, it causes serious wear on the equipment and increases the operating cost of the device; if the particle size is too small, the surface energy becomes high, the interaction force between the particles becomes strong, and it is easy to agglomerate, which is also not conducive to the hydrogenation reaction.

[0013] Secondly, regarding the ratio of spent fixed-bed hydrogenation catalyst particles to iron powder, the present invention strictly controls the ratio of spent fixed-bed hydrogenation catalyst particles to iron powder within a range of 1-4:100. If the iron powder ratio is too high, the spent fixed-bed hydrogenation catalyst will have fewer active metal sites, affecting the hydrogenation effect. If the iron powder ratio is too low, the deposition or conversion of larger molecular weight asphaltenes or colloids (substances that cannot be processed by fixed-bed hydrogenation) in the slurry bed feed will be affected, reducing the conversion rate.

[0014] Finally, in terms of mercaptan polyoxyethylene ether: As is common knowledge in the industry, the smaller the particle size of the slurry bed hydrogenation catalyst, the higher the surface energy, the stronger the interaction force between the particles, the easier it is to agglomerate, which is not conducive to the progress of the hydrogenation reaction. To this end, the present invention has found that after impregnating the catalyst with a specific mercaptan polyoxyethylene ether surfactant, the interaction force between the catalyst particles can be significantly reduced, and the binding force between the catalyst and the oil phase reaction feed is enhanced, so that the macromolecular compounds in the feed are better adsorbed on the active sites, thereby better promoting the progress of the hydrogenation reaction and converting them into small molecular compounds; even if they cannot be hydrogenated, they will be discharged from the reactor together with the catalyst particles and the reaction products, thereby reducing the coke yield and also having the effect of optimizing product distribution. In addition, more importantly, after the catalyst is surface-modified with a mercaptan polyoxyethylene ether surfactant, the thiol groups on such compounds are converted into H2S through hydrogenation reaction, which can increase the H2S concentration in the reaction system, effectively guarantee the activity stability of the regenerated slurry bed hydrogenation catalyst, and facilitate the progress of the hydrogenation reaction. Furthermore, in order to better exert the effect of thiol polyoxyethylene ether, it is necessary to optimize its solution concentration and the ratio with the catalyst during the impregnation process.

[0015] Preferably, in step 1), the carrier of the spent fixed-bed hydrogenation catalyst is selected from alumina and silica-alumina, and the active component is selected from one or more of W, Mo and Ni.

[0016] Preferably, in step 1), the calcination temperature is 1300-1750° C. and the calcination time is 1-8 h.

[0017] Preferably, in step 2), the iron powder is added to the particles of step 1) in a circular manner at 20-35° C., with an addition rate of 0.1-0.4 g / s.

[0018] Preferably, in step 3), the thiol polyoxyethylene ether surfactant is tert-hexylthiol polyoxyethylene (11-12) ether and / or tert-nonylthiol polyoxyethylene (17) ether.

[0019] Preferably, in step 3), the immersion temperature is 20-35° C. and the time is 1-10 h; the drying temperature is 100-130° C. and the time is 1-10 h.

[0020] In a second aspect, the present invention provides use of the above-mentioned regenerated slurry bed hydrogenation catalyst in slurry bed hydrogenation of inferior heavy oil.

[0021] Preferably, the application comprises the following steps:

[0022] A) Inferior heavy oil, sulfur powder and regenerated slurry bed hydrogenation catalyst are mixed to form a slurry hydrogenation bed.

[0023] B) subjecting the slurry hydrogenation bed to a hydrogenation reaction under an atmosphere containing hydrogen.

[0024] C) separating the obtained hydrogenation product to obtain gas, liquid and solid three-phase products.

[0025] After the regenerated slurry bed hydrogenation catalyst of the present invention is mixed with low-quality heavy oil and sulfur powder, it enters the slurry bed hydrogenation reactor for reaction. The hydrogenated products are separated to obtain relatively more liquid products and relatively fewer gaseous products and solid products, thereby optimizing the product distribution. Among them, the gaseous products (including C1 to C4 alkanes, of which C1-C2 is refinery dry gas and C3-C4 is the main component of liquefied gas) can be used as fuel gas; the liquid products with a dry point of less than 520°C (including gasoline, diesel and wax oil fraction mixtures, etc.) have the highest economic value and can be used as feed for fixed-bed hydrogenation units (fixed-bed hydrogenation units generally refer to hydrocracking units in refineries) to produce clean gasoline and diesel products; a small amount of solid products is mainly coke. Therefore, using the regenerated slurry bed hydrogenation catalyst of the present invention and the above-mentioned slurry bed hydrogenation process to treat low-quality heavy oil can convert low-value-added low-quality heavy oil into combustible gas, feed for fixed-bed hydrogenation units, etc., and ultimately into clean fuel products, which can significantly improve economic efficiency.

[0026] Preferably, the inferior heavy oil is selected from vacuum residue, ethylene tar, catalytic oil or coal tar; vacuum residue refers to the heavier fraction obtained by vacuum distillation in the petrochemical industry.

[0027] Preferably, in step A), the regenerated slurry bed hydrogenation catalyst accounts for 0.1-0.5 wt% of the low-quality heavy oil and 80-100 wt% of the sulfur powder.

[0028] Preferably, in step B), the temperature of the hydrogenation reaction is 400-450°C, the pressure is 12-24 MPa, the stirring rate is 350-450 r / r / min, and when the hydrogenation reaction is heated, the heating rate in the range of 200-250°C is 40-50°C / h, and the heating rate in the range of 250-450°C is 180-220°C / h. After reaching the reaction temperature, the reaction is carried out for 30-60 minutes.

[0029] In the inferior heavy oil hydrogenation process of the present invention, the addition of sulfur powder and the use of a slower heating rate in the range of 200-250°C are intended to completely reduce the oxidized active metal components to a sulfide state, which can significantly improve the hydrogenation activity.

[0030] Compared with the prior art, the present invention has the following technical effects:

[0031] (1) The present invention uses environmentally harmful abandoned fixed-bed hydrogenation catalyst as the main component and low-cost iron powder as the auxiliary component to prepare a regenerated slurry-bed hydrogenation catalyst, which has the advantages of simple process, low cost, low carbon and environmental protection.

[0032] (2) The present invention optimizes the particle size and component ratio of the catalyst, so that the resulting catalyst has excellent hydrogenation activity in the hydrogenation reaction of inferior heavy oil, has a higher liquid phase product yield and a lower gas phase product yield than the existing slurry bed catalyst, optimizes the product distribution, and has higher economic value.

[0033] (3) The present invention uses mercaptan polyoxyethylene ether to impregnate the catalyst, which can significantly reduce the interaction between catalyst particles, enhance the binding force between the catalyst and the oil-phase reaction feed, and better adsorb large molecular compounds in the feed onto the active sites, thereby better promoting the hydrogenation reaction and converting them into small molecular compounds. Even if they cannot be hydrogenated, they will be discharged from the reactor along with the catalyst and reaction products, thereby reducing the coke yield. In addition, after the catalyst is surface-modified with mercaptan polyoxyethylene ether, the mercaptan groups are converted into H2S through hydrogenation, which can increase the H2S concentration in the reaction system, thereby effectively ensuring the activity and stability of the regenerated slurry bed hydrogenation catalyst.

[0034] (4) The regenerated slurry bed hydrogenation catalyst and slurry bed hydrogenation process of the present invention are used to treat low-quality heavy oil, which can convert low-value-added low-quality heavy oil into combustible gas, feed for fixed-bed hydrogenation equipment, etc., and finally into clean fuel products, which can significantly improve economic efficiency.

[0035] (5) In the inferior heavy oil hydrogenation process of the present invention, the addition of sulfur powder and the use of a slower heating rate in the range of 200-250°C are intended to completely reduce the oxidized active metal components to the sulfide state, which can significantly improve the hydrogenation activity. DETAILED DESCRIPTION

[0036] The present invention will be further described below with reference to the embodiments.

[0037] Overall embodiment

[0038] A method for preparing a regenerated slurry bed hydrogenation catalyst comprises the following steps:

[0039] 1) Spent fixed-bed hydrogenation catalyst (the carrier is selected from alumina and silica-alumina, and the active component is selected from W, Mo and Ni) is calcined at 1300-1750° C. for 1-8 hours, pulverized, and sieved to obtain particles with a particle size of 50-90 μm.

[0040] 2) Iron powder with a particle size of 50-75 μm and a particle size dispersion of less than 10% is added to the particles in step 1) in a circular manner at a mass ratio of 1-4:100 at 20-35° C. and mixed evenly at an addition rate of 0.1-0.4 g / s.

[0041] 3) impregnating the product obtained in step 2) with 4-10 wt% of a thiol polyoxyethylene ether surfactant (preferably tert-hexyl mercaptan polyoxyethylene (11-12) ether and / or tert-nonyl mercaptan polyoxyethylene (17) ether) solution at a volume ratio of 1-3:1 at 20-35° C. for 1-10 h, drying at 100-130° C. for 1-10 h, and cooling to room temperature to obtain a regenerated slurry bed hydrogenation catalyst with a particle size of 60-100 μm.

[0042] The application of the above-mentioned regenerated slurry bed hydrogenation catalyst in the slurry bed hydrogenation of inferior heavy oil comprises the following steps:

[0043] A) mixing low-quality heavy oil, sulfur powder, and a regenerated slurry bed hydrogenation catalyst to form a slurry hydrogenation bed. The low-quality heavy oil is selected from vacuum residue, ethylene tar, catalytic oil slurry, or coal tar; vacuum residue refers to the heavier fraction obtained from vacuum distillation in the petrochemical industry; and the regenerated slurry bed hydrogenation catalyst accounts for 0.1-0.5 wt% of the low-quality heavy oil and 80-100 wt% of the sulfur powder.

[0044] B) conducting a hydrogenation reaction in the slurry hydrogenation bed at 400-450° C., 12-24 MPa, and 350-450 rpm in a hydrogen atmosphere. During the hydrogenation reaction, the heating rate is 40-50° C. / h in the range of 200-250° C., and 180-220° C. / h in the range of 250-450° C.; and the reaction is continued for 30-60 minutes after reaching the reaction temperature.

[0045] C) Separating the resulting hydrogenated product to obtain gas, liquid, and solid products, wherein the gaseous product is used as fuel gas; the liquid product having a dry point less than 520°C is used as feed for a fixed-bed hydrogenation unit, which generally refers to a hydrocracking unit in an oil refinery and is used to produce clean gasoline and diesel products; and the solid product is coke. Specific embodiments

[0047] The physicochemical properties of various types of waste fixed-bed hydrogenation catalysts, including hydrogenation protectants, hydrogenation refining agents, and hydrocracking agents, are shown in Table 1.

[0048] Table 1: Physicochemical properties of spent fixed-bed hydrogenation catalyst

[0049] serial number category shape carrier Particle size, mm W, wt% Mo, wt% Ni, wt% A Hydrogenation protection catalyst Four-leaf clover strips Alumina 2-3 - 2.0 1.8 B Hydrotreating catalysts Shamrock Strips Alumina 1.2-1.4 - 28.1 6.5 C Hydrocracking catalyst cylindrical bars Silica Aluminum 1.4-1.6 20.5 - 5.1

[0050] It should be noted that the iron powder used in the following examples and comparative examples is Runyang Gold brand iron powder produced by Shijiazhuang Runyang Gold Mineral Products Co., Ltd., with a particle size of 200 mesh (75 μm), 250 mesh (58 μm) and 300 mesh (50 μm), that is, the particle sizes are 75 μm, 58 μm and 50 μm, respectively, and the iron content is more than 97%.

[0051] The spent fixed-bed hydrogenation catalyst is burned in a ZCGWL high-temperature box-type electric furnace produced by Shandong Zhongchen Electric Furnace Co., Ltd., whose heating elements are silicon-molybdenum rods.

[0052] In addition, unless otherwise specified, the raw materials, solvents and reagents used in the following examples and comparative examples of the present invention are all obtained through conventional commercial means.

[0053] Example 1

[0054] 1. Take 100g of spent fixed-bed hydrogenation catalyst A and burn it in a high-temperature box-type electric furnace at 1750℃ for 3h to obtain a powdery substance. Then sieve it with a 300-mesh sieve to obtain particles of about 50μm for use.

[0055] 2. At 25°C, 4 g of iron powder with a particle size of 200 mesh and a particle size dispersion of 7% was added to the product 1 at a rate of 0.2 g / s in a circular manner.

[0056] 3. After immersion in 200 ml of a 6 wt% tert-hexyl mercaptan polyoxyethylene (11-12) ether surfactant solution at 25°C for 10 h, a solid product was obtained. The product was dried at 100°C for 10 h and naturally cooled to 25°C to obtain a regenerated slurry bed hydrogenation catalyst C1 with a particle size of about 65 μm.

[0057] Example 2

[0058] 1. Take 100g of spent fixed-bed hydrogenation catalyst B and burn it in a high-temperature box-type electric furnace at 1600℃ for 8h to obtain a powdery substance. Then sieve it with a 180-mesh sieve to obtain particles of about 88μm for use.

[0059] 2. At 20°C, 3 g of iron powder with a particle size of 250 mesh and a particle size dispersion of 8% was added to the product 1 at a rate of 0.4 g / s in a circular manner.

[0060] 3. At 20°C, soak with 100 ml of 8 wt% tert-hexyl mercaptan polyoxyethylene (11-12) ether surfactant solution for 1 hour to obtain a solid product. This product is dried at 140°C for 7 hours and naturally cooled to 20°C to obtain a regenerated slurry bed hydrogenation catalyst C2 with a particle size of about 70 μm.

[0061] Example 3

[0062] 1. Take 100g of spent fixed-bed hydrogenation catalyst B and burn it in a high-temperature box-type electric furnace at 1450℃ for 1h to obtain a powdery substance. Then sieve it with a 260-mesh sieve to obtain particles of about 57μm for use.

[0063] 2. At 30°C, 2 g of 300 mesh iron powder with a particle size dispersion of 6% was added to the product 1 in a circular manner at a rate of 0.3 g / s.

[0064] 3. After immersion in 300 ml of a 4 wt% tert-nonyl mercaptan polyoxyethylene (17) ether surfactant solution at 30°C for 7 h, a solid product was obtained. The product was dried at 120°C for 4 h and naturally cooled to 30°C to obtain a regenerated slurry bed hydrogenation catalyst C3 with a particle size of about 55 μm.

[0065] Example 4

[0066] 1. Take 100g of spent fixed-bed hydrogenation catalyst C and burn it in a high-temperature box-type electric furnace at 1300℃ for 6h to obtain a powdery substance. Then sieve it with a 200-mesh sieve to obtain particles of about 75μm for use.

[0067] 2. At 35°C, 1 g of 250 mesh iron powder with a particle size dispersion of 5% was added to the product 1 at a rate of 0.1 g / s in a circular motion.

[0068] 3. After immersion in 200 ml of a 10 wt% tert-nonyl mercaptan polyoxyethylene (17) ether surfactant solution at 35°C for 4 h, a solid product was obtained. The product was dried at 160°C for 1 h and naturally cooled to 35°C to obtain a regenerated slurry bed hydrogenation catalyst C4 with a particle size of about 75 μm.

[0069] The above Examples 1-4 illustrate the preparation of regenerated slurry bed hydrogenation catalysts. The following Examples illustrate the use of the above catalysts in slurry bed hydrogenation of vacuum residue.

[0070] The raw material used for the evaluation of the C1-C4 activity of the regenerated slurry bed hydrogenation catalyst obtained in Examples 1-4 of the present invention was vacuum residue oil provided by a refinery in the south, and its specific properties are shown in Table 2.

[0071] Table 2: Properties of vacuum residues used for slurry bed hydrogenation

[0072] Raw oil name Vacuum residue <![CDATA[Density (20 °C), kg / m 3 > 1034.5 Carbon residue / % 23.4 Four components, m% / Saturation 23.8 Aroma 35.9 colloid 22.6 Asphaltene 17.7 Distillation range, ℃ 376-648(70v％) Solid content, g / L 0.3 <![CDATA[Metal content, μg·g -1 > 362

[0073] The equipment for evaluating the activity of C1-C4 in the regenerated slurry bed hydrogenation catalyst obtained in Examples 1-4 of the present invention adopts the BS series stirred high-pressure reactor (volume 0.25L, design pressure 35MPa, design temperature 500°C, stirring speed 0-1500rpm) of Shanghai Laibei Scientific Instrument Co., Ltd., and the hydrogenation product separation adopts the SH / T0165 vacuum distillation apparatus produced by Xi'an Lianxing Experimental Instrument Co., Ltd.

[0074] Examples 5-8

[0075] The regenerated slurry bed hydrogenation catalysts C1-C4 obtained in Examples 1-4 were used to carry out a slurry bed hydrogenation reaction on vacuum residue. First, hydrogen was introduced into the reactor to make the pressure in the reactor reach 24 MPa for leak detection. At the same time, the air in the reactor was discharged. Then, hydrogen was added to make the reactor reach the reaction pressure. The temperature was raised to the reaction temperature. After a certain reaction time at a certain stirring rate, heating and stirring were stopped. The temperature in the reactor was cooled to room temperature to terminate the reaction. The slurry bed hydrogenation reaction conditions corresponded to Examples 5-8, respectively, and are specifically listed in Table 3. The heating rate during the reaction of these four examples was 50°C / h for Examples 5 and 6 in the range of 200-250°C, 40°C / h for Examples 7 and 8 in the range of 200-250°C, and 200°C / h for these four examples in the range of 250-450°C.

[0076] The sulfur powder used in the experiment was reagent-grade. The feed and sulfur powder addition amounts for the regenerated slurry bed hydrogenation catalyst are also listed in Table 3.

[0077] After the reaction is completed, the product in the reactor is collected and weighed, and then subjected to reduced pressure distillation. After the distillation is completed, the residue in the distillation flask is washed with toluene, and the coke in the liquid phase is obtained after centrifugation and drying.

[0078] The experimental evaluation indicators include raw material conversion rate (also known as total yield), distillate oil yield, metal removal rate and coking rate:

[0079] Feedstock conversion rate = (distillate oil + gas) / feedstock oil × 100%.

[0080] Distillate oil yield = distillate oil below 520°C / feed oil × 100%.

[0081] Metal removal rate = (1-metal content in liquid product / metal content in feed oil) × 100%.

[0082] Coke yield = toluene insoluble matter / raw oil × 100%.

[0083] Table 3: Performance evaluation results of regenerated slurry bed hydrogenation catalysts of Examples 5-8

[0084]

[0085] As can be seen from Table 3, the regenerated slurry bed hydrogenation catalyst prepared by using discarded fixed-bed hydrogenation catalysts that have an impact on the environment and iron powder in the present invention shows good catalytic activity when treating low-quality heavy oil - vacuum residue oil. The raw material conversion rate and distillate oil yield are high, and the metal removal rate is also high, especially the distillate oil yield below 520°C is high. This means that the activity and stability of the catalyst can be better protected during the next fixed-bed hydrogenation reaction, and high-value-added clean gasoline and diesel products are finally obtained. The economic efficiency of low-value-added vacuum residue oil is improved; on the other hand, the coking rate is less than 1%, indicating that the catalyst of the present invention has a very broad industrial application prospect. When applied to industrial equipment, the equipment can be stably operated. In summary, the catalyst provided by the embodiment of the present invention, its preparation method and application will produce good economic and social benefits after industrialization.

[0086] Comparative Example 1

[0087] Catalyst DC1 was obtained by replacing the spent fixed-bed hydrogenation catalyst powder in step 1 of Example 1 with alumina powder, with all other parameters unchanged. This catalyst was used in a catalytic hydrogenation reaction using the conditions of Example 5, resulting in a feedstock conversion of 68.2%, a metal removal rate of 85.0%, and a coke formation rate of 4.8%. These results were significantly lower than those of Example 1 of the present invention, demonstrating that the present invention achieves superior catalytic hydrogenation performance using spent fixed-bed hydrogenation catalyst as a slurry-bed hydrogenation catalyst.

[0088] Comparative Example 2

[0089] Catalyst DC2 was obtained by replacing the spent fixed-bed hydrogenation catalyst powder from step 1 of Example 1 with a 350-mesh particle size, while maintaining all other parameters unchanged. This catalyst was used in a catalytic hydrogenation reaction using the conditions of Example 5, resulting in a feedstock conversion of 86.5%, a metal removal rate of 84.4%, and a coke formation rate of 4.6%, significantly lower than those of Example 1.

[0090] Comparative Example 3

[0091] Catalyst DC3 was obtained by replacing the spent fixed-bed hydrogenation catalyst powder from step 1 of Example 1 with a 160-mesh particle size, while maintaining all other parameters unchanged. This catalyst was used in a catalytic hydrogenation reaction using the conditions of Example 5, resulting in a feedstock conversion of 87.0%, a metal removal rate of 85.2%, and a coke formation rate of 3.6%, significantly lower than those of Example 1.

[0092] Comparative Example 4

[0093] Catalyst DC4 was obtained by replacing the iron powder in step 2 of Example 1 with a powder of the same particle size but with a 20% particle size dispersion, while maintaining all other parameters unchanged. This catalyst was used in a catalytic hydrogenation reaction using the conditions of Example 5, resulting in a feedstock conversion of 78.4%, a metal removal rate of 75.8%, and a coke yield of 4.6%, significantly lower than those of Example 1 of the present invention.

[0094] Comparative Example 5

[0095] Catalyst DC5 was obtained by replacing the iron powder in step 2 of Example 1 with a 160-mesh powder of the same particle size dispersion, while maintaining all other parameters unchanged. This catalyst was used in a catalytic hydrogenation reaction using the conditions of Example 5, resulting in a feedstock conversion of 79.0%, a metal removal rate of 76.1%, and a coke yield of 3.9%, significantly lower than those of Example 1 of the present invention.

[0096] Comparative Example 6

[0097] Catalyst DC6 was obtained by replacing the iron powder in step 2 of Example 1 with a 350-mesh powder of the same particle size dispersion, while maintaining all other parameters unchanged. This catalyst was used in a catalytic hydrogenation reaction using the conditions of Example 5, resulting in a feedstock conversion of 83.90%, a metal removal rate of 80.7%, and a coke yield of 4.1%, significantly lower than those of Example 1 of the present invention.

[0098] Comparative Example 7

[0099] Catalyst DC7 was obtained by replacing the iron powder in step 2 of Example 1 with alumina powder, with all other conditions unchanged. This catalyst was used in a catalytic hydrogenation reaction using the conditions of Example 5, resulting in a feedstock conversion of 64.1%, a metal removal rate of 81.9%, and a coke formation rate of 4.8%, significantly lower than those of Example 1. This demonstrates that the preferred iron powder of the present invention has a significant catalytic hydrogenation effect as an additive component to a slurry bed hydrogenation catalyst.

[0100] Comparative Example 8

[0101] A slurry bed hydrogenation reaction was conducted using a C1 catalyst. The reactor heating rate was 100°C / h in the 200-250°C range and 200°C / h in the 250-450°C range. Other conditions were the same as in Example 5. The resulting feedstock conversion was 91.0%, the metal removal rate was 88.9%, and the coke yield was 4.1%, significantly lower than that of Example 5.

[0102] Comparative Example 9

[0103] Catalyst DC8 was obtained by replacing the tert-hexylmercaptan polyoxyethylene (11-12) ether in step 3 of Example 1 with an anionic surfactant, sodium alkylbenzene sulfonate, while maintaining all other properties. This catalyst was used in a catalytic hydrogenation reaction using the conditions of Example 5, resulting in a feedstock conversion of 82.4%, a metal removal rate of 80.6%, and a coke yield of 6.1%, significantly lower than those of Example 1.

[0104] Comparative Example 10

[0105] Catalyst DC9 was obtained by replacing the tert-hexyl mercaptan polyoxyethylene (11-12) ether in step 3 of Example 1 with another nonionic surfactant, alkylphenol polyoxyethylene ether, while maintaining all other properties unchanged. This catalyst was used in a catalytic hydrogenation reaction using the conditions of Example 5, resulting in a feedstock conversion of 86.1%, a metal removal rate of 85.0%, and a coke yield of 5.3%, significantly lower than those of Example 1.

[0106] Comparative Example 11

[0107] Catalyst DC10 was obtained by replacing the 200 ml of tert-hexylmercaptan polyoxyethylene (11-12) ether solution in step 3 of Example 1 with 1000 ml of the solution, with all other conditions remaining unchanged. This catalyst was used in a catalytic hydrogenation reaction using the conditions of Example 5, resulting in a feedstock conversion of 79.3%, a metal removal rate of 74.1%, and a coke yield of 5.8%, significantly lower than those of Example 1.

[0108] Comparative Example 12

[0109] Catalyst DC11 was obtained by replacing 100 g of spent fixed-bed hydrogenation catalyst A in step 3 of Example 1 with 1000 g, with all other ingredients remaining unchanged. This catalyst was used in a catalytic hydrogenation reaction using the conditions of Example 5, resulting in a feedstock conversion of 82.8%, a metal removal rate of 78.2%, and a coke yield of 5.3%, significantly lower than those of Example 1.

[0110] Unless otherwise specified, the raw materials and equipment used in the present invention are commonly used in the art; the methods used in the present invention are conventional methods in the art unless otherwise specified.

[0111] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent transformation made to the above embodiment based on the technical essence of the present invention still fall within the scope of protection of the technical solution of the present invention.

Claims

1. A method for preparing a regenerated slurry bed hydrogenation catalyst, characterized in that The following steps are involved: 1) The spent fixed-bed hydrogenation catalyst is burned, pulverized, and sieved to obtain particles with a particle size of 50-90 μm; 2) adding iron powder with a particle size of 50-75 μm and a particle size dispersion of less than 10% to the particles prepared in step 1) at a mass ratio of 1-4:100 and mixing evenly; 3) impregnating the product obtained in step 2) with a 4-10 wt % solution of a mercaptan polyoxyethylene ether surfactant at a ratio of 1-3 mL / 1 g, drying, and cooling to obtain a regenerated slurry bed hydrogenation catalyst with a particle size of 60-100 μm.

2. The preparation method according to claim 1, wherein: In step 1), the carrier of the spent fixed-bed hydrogenation catalyst is selected from alumina and silica-alumina, and the active component is selected from one or more of W, Mo and Ni.

3. The preparation method according to claim 1 or 2, wherein: In step 1), the calcination temperature is 1300-1750° C. and the calcination time is 1-8 hours.

4. The preparation method according to claim 1, wherein: In step 2), the iron powder is added to the particles in step 1) in a circular manner at 20-35° C., with an addition rate of 0.1-0.4 g / s.

5. The preparation method according to claim 1, wherein: In step 3), the thiol polyoxyethylene ether surfactant is tert-hexyl thiol polyoxyethylene (11-12) ether and / or tert-nonyl thiol polyoxyethylene (17) ether.

6. The preparation method according to claim 1 or 5, wherein: In step 3), The immersion temperature is 20-35°C and the time is 1-10 hours; The drying temperature is 100-130° C. and the drying time is 1-10 hours.

7. Use of the regenerated slurry bed hydrogenation catalyst obtained by the preparation method according to any one of claims 1 to 6 in the slurry bed hydrogenation of inferior heavy oil.

8. The use according to claim 7, characterized in that The following steps are involved: A) mixing inferior heavy oil, sulfur powder and regenerated slurry bed hydrogenation catalyst to form a slurry hydrogenation bed; B) subjecting the slurry hydrogenation bed to a hydrogenation reaction under an atmosphere comprising hydrogen; C) The resulting hydrogenation products are separated to obtain gas, liquid, and solid products. The gaseous product is used as fuel gas; the liquid product with a dry point less than 520°C is used as feed for a fixed-bed hydrogenation unit to produce clean gasoline and diesel products; and the solid product is coke.

9. The use according to claim 7 or 8, characterized in that: The inferior heavy oil is selected from vacuum residue, ethylene tar, catalytic slurry oil or coal tar.

10. The use according to claim 7 or 8, characterized in that: In step A), the regenerated slurry bed hydrogenation catalyst accounts for 0.1-0.5wt% of the low-quality heavy oil and 80-100wt% of the sulfur powder; In step B), the hydrogenation reaction temperature is 400-450°C, the pressure is 12-24 MPa, and the stirring rate is 350-450 r / min. When the hydrogenation reaction temperature is increased, the heating rate in the range of 200-250°C is 40-50°C / h, and the heating rate in the range of 250-450°C is 180-220°C / h. After reaching the reaction temperature, the reaction is carried out for 30-60 minutes.

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