Regeneration method of hydrogenation waste catalyst and cracking C9 + component hydrogenation catalyst

Abstract

The invention provides a regeneration method of a hydrogenation waste catalyst and a cracking C9 + component hydrogenation catalyst. The regeneration method comprises the following steps: S1, nitrogen purging; step S2, water vapor purging; step S3, calcining; step S4, prevulcanization: step S4-1, in a nitrogen atmosphere, performing first prevulcanization on the third product obtained by calcination to obtain a fourth product; step S4-2, in a hydrogen atmosphere, using dimethyl disulfide as a vulcanizing agent, and carrying out second pre-vulcanization on the fourth product to obtain a fifth product; and S4-3, sequentially carrying out third prevulcanization and cooling treatment on the fifth product to obtain the regenerated hydrogenation catalyst. Through fine multi-step treatment, deposited carbon and sulfide on the surface of the waste catalyst are effectively removed, the activity of the catalyst is recovered, and the repeated utilization rate of the catalyst is increased. The activity and selectivity of the regenerated hydrogenation catalyst are close to those of a new catalyst.

Description

Technical Field

[0001] The present invention relates to the field of hydrogenation catalysts, and in particular to a method for regenerating a spent hydrogenation catalyst and a cracking C9+ component hydrogenation catalyst. Background Art

[0002] The cracked C9+ component, i.e. the heavy gasoline fraction, is one of the main by-products of the ethylene plant. It is currently sold as a relatively cheap primary raw material, and only a small number of plants process it as a gasoline, diesel blending component or solvent oil. The cracked C9+ component contains a large amount of aromatics and olefin aromatics, which are similar to the physical and chemical properties and uses of coal-based diesel component oil. There is a price difference when it is sold as a diesel component oil product. The cracked C9+ component can be hydrodesulfurized and olefin-reduced and then blended into the diesel component oil to prepare a vehicle diesel component oil that meets the standards and then sell it to achieve the value-added utilization of the cracked C9+ component. Therefore, the hydrogenation technology of the cracked C9+ component occupies an important position in the comprehensive utilization of the C9+ component, and has broad application prospects due to the high added value of the hydrogenated products.

[0003] At the same time, in general, the sulfur content and olefin content of the cracking byproduct C9+ component are high, and as a blending component of diesel, the sulfur content and oxidation stability of the diesel component will exceed the standard. Therefore, sulfur content and oxidation stability are the main factors that limit the blending of two oil products as qualified automotive diesel component oils.

[0004] At present, in view of the characteristics of raw materials with excessive sulfur content and oxidation stability of cracking C9+ products, a two-stage hydrogenation catalyst has been developed. The first-stage hydrogenation catalyst and its corresponding process first hydrogenate to remove easily polymerized components such as dienes and conjugated olefins under low temperature conditions, and the second-stage hydrogenation catalyst and its corresponding process hydrogenate to saturate the remaining olefins, and then send them to be blended with diesel component oil after desulfurization. The hydrogenation catalyst for cracking C9+ components mainly uses metal sulfide catalysts such as Co-Mo, Ni-Mo, and Ni-Co-Mo. Nickel-based catalysts have low requirements for poisons such as sulfur and arsenic in the raw materials, a wide range of raw oil fractions, high activity, and can operate at moderate temperatures, which is superior to palladium-based catalysts and Co-Mo-Ni-based catalysts with high-temperature activity. The active components Ni and / or Mo of the two-stage hydrogenation catalyst exist in the catalyst in an oxidized state after new loading and regeneration. In actual use, before the hydrogenation conversion reaction, the hydrogenation catalyst needs to be pre-sulfurized to reduce the oxidized active metals to sulfide active substances. Only sulfided Ni and / or Mo catalysts have hydrogenation and desulfurization activity.

[0005] However, under the conditions of hydrogenation reaction, the above-mentioned cracking C9+ component hydrogenation catalyst is prone to carbon deposition and low molecular weight polymers during use, resulting in deactivation. At the same time, since industrial hydrogenation catalysts usually need to be used for more than 2 cycles and the catalysts operate normally for about 2 to 3 years, the reactor inlet temperature must be gradually increased to ensure that the hydrogenation products are qualified. When the temperature reaches the upper limit of operation, the deactivated hydrogenation catalyst needs to be regenerated by burning carbon to restore most of the activity of the catalyst, so as to achieve the purpose of repeated use. Due to the cost of the catalyst, the consumption of manpower and material resources during the replacement process, and the losses caused by shutdown, the regeneration and activation of the catalyst is particularly important.

[0006] At present, there are two main methods for the regeneration of cracking C9+ component hydrogenation catalysts: air combustion and hydrogen thermal stripping. The specific air combustion method is as follows: 1. Pretreatment: Before regeneration begins, the catalyst needs to be deoiled and the heating furnace needs to be decoked to ensure the cleanliness of the catalyst surface. 2. Coke regeneration: By gradually increasing the coke temperature and reducing the oxygen concentration, the coke process is controlled to be completed in three stages. In this stage, the bed temperature needs to be closely monitored to prevent the bed temperature from rising too fast or too violently to avoid damage to the catalyst. 3. Cooling and regeneration end: After regeneration, air is introduced to cool down, and then nitrogen is used to blow out the powdered catalyst. During this process, air is continued to cool down, and a nitrogen switching device is used to perform presulfurization operations to prepare for the next use. It has a significant carbon removal effect, and the hydrogenation product has low colloid after regeneration and activation. However, the high calcination temperature easily causes the catalyst grains to grow and reduce the specific surface area, and the service life and load are short after regeneration and activation. The main process of hydrogen hot stripping is as follows: 1. Hydrogen purging: First, at a temperature of 130℃~170℃ and a system pressure of 0.15MPa~0.25MPa, hydrogen is purged for 3~5 hours to remove the oil on the deactivated catalyst bed. 2. Superheated steam purging: Then, the catalyst bed is purged with superheated steam at 1.5MPa~2.0MPa until the oil and low molecular polymers on the surface of the catalyst bed are completely removed. 3. Hydrogen reduction activation: Hydrogen is passed through the catalyst bed at 0.2MPa~0.25MPa for reduction activation, and the reduction activation temperature is 200℃~350℃. The process is simple and time-saving; the catalyst specific surface area is less degraded, and the service life is long after regeneration. However, the carbon removal effect is not obvious, the hydrogenation product has high colloid after regeneration and activation, and the service life and load after regeneration and activation are short.

[0007] Based on this, in view of the shortcomings of existing regeneration and activation methods, how to provide a regeneration method for hydrogenation waste catalysts, and then provide a waste catalyst-based cracking C9+ component hydrogenation catalyst with high catalytic activity, is one of the important technical problems that need to be solved in this field. Summary of the invention

[0008] The main purpose of the present invention is to provide a method for regenerating a spent hydrogenation catalyst and a hydrogenation catalyst for cracking C9+ components, so as to solve the problem in the prior art that it is difficult to regenerate a hydrogenation catalyst for cracking C9+ components with high catalytic activity.

[0009] In order to achieve the above-mentioned purpose, the first aspect of the present invention provides a method for regenerating a hydrogenation waste catalyst, comprising: step S1, nitrogen purging: nitrogen purging the hydrogenation waste catalyst to obtain a first product; step S2, water vapor purging: water vapor purging the first product to obtain a second product; step S3, calcination: calcining the second product in an air atmosphere to obtain a third product; step S4, presulfurization: step S4-1, in a nitrogen atmosphere, performing a first presulfurization on the third product to obtain a fourth product; step S4-2, in a hydrogen atmosphere, using dimethyl disulfide as a sulfiding agent, performing a second presulfurization on the fourth product to obtain a fifth product; step S4-3, the fifth product is sequentially subjected to a third presulfurization and a cooling treatment to obtain a regenerated hydrogenation catalyst.

[0010] Furthermore, the spent hydrogenation catalyst is a Ni-Mo metal sulfide spent catalyst used for two-stage hydrogenation catalysis of cracking C9+ components. The active components of the spent hydrogenation catalyst are Ni and / or Mo, and based on the total weight of the spent hydrogenation catalyst as 100%, the content of Ni is 3% to 20%, and the content of Mo is 15% to 30%.

[0011] Furthermore, in step S1, the nitrogen mass space velocity used for nitrogen purging is 0.5h -1 ~0.8h -1 The temperature of nitrogen purge is 180℃~200℃, and the time is 2h~2.5h.

[0012] Furthermore, in step S2, the water vapor mass space velocity used for water vapor purge is 0.5h -1 ~0.8h -1 , and the water vapor purge includes a first water vapor purge and a second water vapor purge performed sequentially; preferably, the temperature of the first water vapor purge is 200℃~300℃, and the time is 10h~12h; and / or, the temperature of the second water vapor purge is 380℃~400℃, and the time is 2h~3h.

[0013] Furthermore, in step S3, the calcination temperature is 350°C to 450°C, and the time is 4h to 5h; preferably, the second product produces a calcination tail gas containing CO and CO2 during the calcination process, and the calcination is terminated when the contents of CO and CO2 in the calcination tail gas are both less than 0.3mol%.

[0014] Furthermore, in step S4-1, the temperature of the first pre-sulfurization is 130°C to 140°C, and the time is 4h to 5h; preferably, in step S4-1, the oxygen content of the nitrogen atmosphere is less than 0.2 vol%.

[0015] Further, step S4-2 comprises: heating the fourth product to 150°C to 155°C in a hydrogen atmosphere at 0.05 m 3 / h~0.06m 3 / h flow rate of sulfiding agent to increase the hydrogen sulfide content in the hydrogen atmosphere; when the volume concentration of hydrogen sulfide in the hydrogen atmosphere reaches 0.45% to 0.50%, the fourth product is heated to 230°C to 240°C, and the injection flow rate of the sulfiding agent is increased to 0.08m 3 / h~0.10m 3 / h, and after heating for 1.5h to 2.0h, the fifth product is obtained.

[0016] In step S4-3, the third pre-vulcanization includes one-stage heating, two-stage heating and three-stage heating in sequence, and: the temperature of the first stage heating is 240℃~250℃, and the time is 3h~3.5h; the temperature of the second stage heating is 280℃~300℃, and the time is 10h~12h; the temperature of the third stage heating is 350℃~360℃, and the time is 12h~14h.

[0017] Furthermore, in step S4-3, the fifth product generates presulfurized tail gas during the third presulfurization process, and when the sulfur concentration in the presulfurized tail gas is greater than 20000 ppm, a temperature reduction treatment is performed.

[0018] The second aspect of the present invention provides a cracking C9+ component hydrogenation catalyst, which is a regenerated hydrogenation catalyst obtained by regenerating the waste catalyst generated in the cracking C9+ component hydrogenation process through the above-mentioned hydrogenation waste catalyst regeneration method.

[0019] By applying the technical solution of the present invention, carbon deposits and sulfides on the surface of the waste catalyst are effectively removed through a sophisticated multi-step treatment, the activity of the catalyst is restored, and its reuse rate is increased. The activity and selectivity of the regenerated hydrogenation catalyst are close to the level of the new catalyst, which significantly reduces the cost of the catalyst and reduces the impact of the waste catalyst on the environment. In addition, the method is simple to operate and easy to apply on an industrial scale, providing an economical and environmentally friendly catalyst regeneration solution for the petrochemical industry. DETAILED DESCRIPTION

[0020] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below in conjunction with the embodiments.

[0021] As described in the background technology, there is a problem in the prior art that it is difficult to regenerate a hydrogenation catalyst for cracking C9+ components with high catalytic activity. In order to solve the above technical problems, the first aspect of the present invention provides a method for regenerating a hydrogenation waste catalyst, comprising: step S1, nitrogen purging: nitrogen purging the hydrogenation waste catalyst to obtain a first product; step S2, water vapor purging: water vapor purging the first product to obtain a second product; step S3, calcination: calcining the second product in an air atmosphere to obtain a third product; step S4, presulfurization: step S4-1, in a nitrogen atmosphere, the third product is subjected to a first presulfurization to obtain a fourth product; step S4-2, in a hydrogen atmosphere, using dimethyl disulfide as a sulfiding agent, the fourth product is subjected to a second presulfurization to obtain a fifth product; step S4-3, the fifth product is subjected to a third presulfurization and a cooling treatment in sequence to obtain a regenerated hydrogenation catalyst.

[0022] The regeneration method provided by the present invention is aimed at hydrogenation waste catalysts. By accurately designing the process flow, the carbon deposits and sulfides on the surface of the waste catalysts are effectively removed, and the hydrogenation catalytic activity is restored. As the background technology said, the air combustion method has a high calcination temperature, which is easy to make the catalyst grains grow and reduce the specific surface area, and the catalytic activity is also reduced. The hydrogen hot stripping method has an insignificant effect on carbon removal, and the hydrogenation product has high colloid after regeneration and activation, and the service life and load after regeneration and activation are short. The present invention first removes the oil and loose carbonaceous deposits on the surface of the waste catalyst by nitrogen purging, and then uses water vapor purging combined with air calcination to remove the carbon deposits on the surface and in the pores of the waste catalyst. Then, the oxidized part of the waste catalyst is reduced and activated by pre-sulfurization method combined with hydrogen reduction, while protecting the catalyst structure, the carbon deposits and oxides on the waste catalyst are removed more deeply, achieving a significant activation effect, and at the same time, it can ensure the service life of the regenerated hydrogenation catalyst obtained after activation. That is to say, the above regeneration method provided by the present invention effectively solves the shortcomings of using air calcination method and hydrogen hot stripping method alone, thereby effectively ensuring that the deactivated hydrogenation waste catalyst recovers a higher catalytic activity.

[0023] In practical applications, dimethyl disulfide (DMDS) as a sulfiding agent is added in the form of a cracked mixed diesel component, and the content of DMDS in the cracked mixed diesel used is 2 wt% to 6 wt%.

[0024] In particular, the above steps in the regeneration method provided by the present invention cooperate with each other as an overall technical solution, that is, forming a complete technical route of nitrogen purging → water vapor purging → calcination arrow presulfurization, for the regeneration of hydrogenation waste catalyst, compared with the conventional methods commonly used in the art including air calcination method and hydrogen hot gas stripping method, the catalytic activity of the obtained regenerated hydrogenation catalyst is higher. In other words, the above steps in the regeneration method provided by the present invention, in addition to the advantages they have themselves, are more importantly able to cooperate with each other, that is, as an overall solution, to achieve efficient activation and regeneration of hydrogenation waste catalyst.

[0025] As for the specific type of hydrogenation waste catalyst, the inventors have preferred the hydrogenation waste catalyst to be a Ni-Mo metal sulfide waste catalyst used for two-stage hydrogenation catalysis of cracking C9+ components after a large number of experiments, wherein the active components are Ni and / or Mo, and based on the total weight of the hydrogenation waste catalyst as 100%, the content of Ni is 3% to 20%, and the content of Mo is 15% to 30%. In theory, the regeneration method provided by the present invention can be applied to a variety of hydrogenation waste catalysts commonly used in the art. However, compared with other types of hydrogenation waste catalysts, the above-mentioned hydrogenation waste catalyst can be better adapted to each process step when the regenerated catalyst is obtained by the regeneration method provided by the present invention, thereby obtaining a more efficient regeneration, and the obtained regenerated product also exhibits a higher hydrogenation activity.

[0026] Generally speaking, the Ni-Mo metal sulfide waste catalyst used for the two-stage hydrogenation catalysis of cracking C9+ components can be divided into a first-stage catalyst and a second-stage catalyst in actual production, and the two can also be used in coordination to catalyze the C9+ raw materials to remove diolefins, sulfur and olefin components through two-stage series reactions. Specifically, in the first-stage Ni-Mo metal sulfide waste catalyst, the Ni content is 3% to 10%, and the Mo content is 14% to 20%; in the second-stage Ni-Mo metal sulfide waste catalyst, the Ni content is 7% to 20%, and the Mo content is 20% to 30%.

[0027] In order to more effectively remove the light carbon deposits on the surface of the spent catalyst and create better conditions for the subsequent steam purge, thereby obtaining a regenerated hydrogenation catalyst with higher activity, it is preferred that in step S1, the nitrogen mass space velocity used for nitrogen purge is 0.5h -1 ~0.8h -1 The temperature of nitrogen purge is 180℃~200℃, and the time is 2h~2.5h.

[0028] In several typical implementations, in step S2, the water vapor mass space velocity used for water vapor purge is 0.5h -1 ~0.8h -1, and the water vapor purge includes a first water vapor purge and a second water vapor purge performed in sequence, and preferably the temperature of the first water vapor purge is 200℃~300℃, and the time is 10h~12h; and / or, the temperature of the second water vapor purge is 380℃~400℃, and the time is 2h~3h. This method of performing water vapor purge in sections according to specific temperature and time intervals can more thoroughly remove carbon deposits and metal oxides inside the waste catalyst, especially the low-temperature first purge at a temperature of 200℃~300℃ can effectively decompose carbon deposits on the surface and inside of the waste catalyst, preparing for the subsequent second purge, and the high-temperature second purge at a temperature of 380℃~400℃ can further remove stubborn carbon deposits inside the catalyst while protecting the catalyst structure, thereby further improving the activity and stability of the regenerated catalyst.

[0029] Furthermore, the calcination temperature in step S3 is preferably 350°C to 450°C, more preferably 400°C to 420°C, and the time is 4h to 5h, so as to more thoroughly oxidize the organic matter and sulfide remaining on the surface of the waste catalyst and improve its catalytic activity after regeneration. During the calcination of the second product, a calcination tail gas containing CO and CO2 is generated. In order to better protect the microstructure of the catalyst and extend its service life, the calcination is preferably terminated when the contents of CO and CO2 in the calcination tail gas are both less than 0.3 mol%.

[0030] Specifically, during the actual calcination process, the catalyst bed temperature in the reactor should be carefully observed to understand the calcination situation. If the bed temperature increases too quickly, the air should be stopped, and after 60 minutes, the air should be introduced again at half the initial amount. The combustion of the coke on the catalyst surface moves from top to bottom, and the temperature movement distribution of the entire bed layer explains the progress of calcination.

[0031] In the presulfidation process, since the active components of the catalyst after calcination are all in an oxidized state, they need to be presulfided in order to restore their catalytic activity. In the preferred step S4-1, the temperature of the first presulfidation is 130°C to 140°C, and the time is 4h to 5h, so as to preliminarily restore the sulfurization state of the active components in the catalyst at this time, thereby effectively improving the activity and stability of the regenerated catalyst. In the preferred step S4-1, the oxygen content of the nitrogen atmosphere is lower than 0.2vol%, so that the presulfidation process can be carried out in an oxygen-free environment as much as possible, inhibiting the re-oxidation of the active components on the catalyst surface, and effectively improving the activity and stability of the regenerated catalyst obtained.

[0032] In several typical embodiments, step S4-2 preferably comprises: heating the fourth product to 150° C. to 155° C. at 0.05 m / s in a hydrogen atmosphere; 3 / h~0.06m 3 / h flow rate of sulfiding agent is injected to increase the content of hydrogen sulfide in the hydrogen atmosphere. In this process, the above-mentioned mild presulfiding conditions can promote the sulfidation of the catalyst and reduce the damage of high temperature to the catalyst structure. At the same time, further preferred step S4-2: when the volume concentration of hydrogen sulfide in the hydrogen atmosphere reaches 0.45% to 0.50%, the fourth product is heated to 230°C to 240°C, and the injection flow rate of the sulfiding agent is increased to 0.08m 3 / h~0.10m 3 / h, and then heated for 1.5h to 2.0h to obtain the fifth product. In this process, the relatively strong sulfurization conditions can make the active components in the catalyst undergo deeper sulfurization and restore their original activity. The staged and coordinated design of the temperature and the sulfurizing agent can better enable the sulfurizing agent dimethyl disulfide to play a sulfurizing role, reducing the active components in the catalyst to a sulfurized state, thereby significantly improving the catalytic activity of the regenerated catalyst.

[0033] After the second presulfurization is completed, in order to promote more complete sulfurization of the active components in the catalyst and thereby restore it to its original activity and stability, in several more typical embodiments, in step S4-3, the third presulfurization includes one-stage heating, two-stage heating and three-stage heating in sequence, and: the temperature of the first stage heating is 240°C to 250°C, and the time is 3h to 3.5h; the temperature of the second stage heating is 280°C to 300°C, and the time is 10h to 12h; the temperature of the third stage heating is 350°C to 360°C, and the time is 12h to 14h.

[0034] Furthermore, in order to allow the sulfiding agent in the presulfurization process to be more fully absorbed and at the same time reduce the impact of oversulfurization on the performance of the resulting regenerated catalyst, thereby obtaining a regenerated hydrogenation catalyst with higher catalytic activity, it is preferred that in step S4-3, the fifth product produces a presulfurized tail gas during the third presulfurization process, and when the sulfur concentration in the presulfurized tail gas is greater than 20000 ppm, a cooling treatment is performed.

[0035] The second aspect of the present invention provides a cracking C9+ component hydrogenation catalyst, which is a regenerated hydrogenation catalyst obtained by regenerating the waste catalyst generated in the cracking C9+ component hydrogenation process through the above-mentioned hydrogenation waste catalyst regeneration method. The hydrogenation catalyst regenerated by the above-mentioned regeneration method of the present invention has an activity and selectivity close to the level of a new catalyst, which can significantly reduce the use cost of the catalyst in the hydrogenation reaction of the cracking C9+ component, and at the same time reduce the adverse impact of the discarded cracking C9+ component hydrogenation catalyst on the environment.

[0036] The present application is further described in detail below in conjunction with specific embodiments. These embodiments should not be construed as limiting the scope of protection claimed in the present application.

[0037] Unless otherwise defined, all professional terms used below have the same meanings as those generally understood by those skilled in the art. The professional terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of the present invention.

[0038] Example 1

[0039] A method for regenerating a spent hydrogenation catalyst:

[0040] The Ni-Mo metal sulfide waste catalyst used for two-stage hydrogenation catalysis of cracking C9+ components was taken as the treatment object, wherein the content of Ni element was 7wt% and the content of Mo element was 22wt%.

[0041] (1) The reactor used for the hydrogenation catalysis of the cracking C9+ components was shut down and switched to the regeneration condition, isolated from the process system, connected to the regeneration system, and used as the reactor for the regeneration method. Nitrogen purging was started: 0.5 h -1 Nitrogen was introduced into the reactor at a mass space velocity of , and the bed temperature of the reactor was raised to 200° C. and maintained at this temperature for 2 hours to complete nitrogen purging to obtain the first product.

[0042] (2) 0.5h -1 The reactor was purged with water vapor at a mass space velocity of 1.5 s / min and the bed temperature of the reactor was kept at 200°C for 12 hours to complete the first water vapor purge. -1 Water vapor is introduced into the reactor at a mass space velocity of , and the bed temperature of the reactor is raised to 380°C at a heating rate of 30°C / h. The temperature is maintained constant for 3 hours to complete the second water vapor purge and obtain the second product.

[0043] (3) Slowly introduce air into the steam pipeline connected to the reactor for calcination, and gradually increase the air flow rate according to the charring situation. During the entire calcination process, the bed temperature is 420°C and maintained for 4 hours. At this time, the contents of CO and CO2 in the calcination tail gas at the reactor outlet are analyzed. When the contents of both are less than 0.3 mol%, the calcination is considered complete, and the air is turned off to terminate it, and the third product is obtained.

[0044] (4) The temperature was lowered at a rate of 30°C / h. When the reactor inlet temperature reached 200°C, nitrogen was used for cooling until the reactor outlet temperature was less than 40°C. All valves were closed and the pressure was maintained at 0.3 MPa with N2. At the same time, the pre-sulfurization procedure was started.

[0045] (4-1) A nitrogen atmosphere is provided to the reactor by using a nitrogen replacement reaction system, and the oxygen content therein is reduced to less than 0.2 vol%, and a first pre-sulfurization is performed at a pressure of 3.0 MPa to obtain a fourth product; the first pre-sulfurization temperature is 140° C. and the time is 4 h.

[0046] (4-2) Switch nitrogen to H2, i.e., -1 Hydrogen was introduced into the reactor at a mass space velocity of 0.05 m / s to establish a circulation, and the fourth product was heated to 150°C. 3 / h injection of cracked mixed diesel (containing 6wt% dimethyl disulfide (DMDS), DMDS as a vulcanizing agent), so that the hydrogen sulfide content in the hydrogen atmosphere increases; when the volume concentration of hydrogen sulfide in the hydrogen atmosphere reaches 0.50%, the fourth product is heated to 230°C, and the injection amount of cracked mixed diesel is gradually increased to 0.08m 3 / h, and after heating for 2.0h, the fifth product was obtained.

[0047] (4-3) The third presulfurization includes: heating the fifth product at 250°C for 3 hours; then heating the fifth product at 280°C for 12 hours at a heating rate of 10°C / h; continuing to heat the fifth product to 360°C and heating the fifth product at this temperature for 12 hours. During the third presulfurization process, presulfurized tail gas is generated at the reactor outlet. When the outlet sulfur concentration is greater than 20000ppm, the heating is terminated. After the heating is completed, the temperature is lowered at 20°C / h, with the first temperature lowered to 50°C and the second temperature lowered to 300°C. During the cooling process, cracking mixed diesel is continuously injected. After the temperature drops to the target temperature, the injection is stopped and the temperature is stabilized for another 5 hours. The presulfurization process is terminated, the reaction pipeline is cleaned, and a regenerated hydrogenation catalyst that can continue to be used for the hydrogenation reaction of the cracking C9+ component is obtained.

[0048] Example 2

[0049] A method for regenerating a spent hydrogenation catalyst:

[0050] The Ni—Mo metal sulfide waste catalyst in Example 1 was taken as the treatment object.

[0051] (1) The reactor used for the hydrogenation catalysis of the cracking C9+ components was shut down and switched to the regeneration condition, isolated from the process system, connected to the regeneration system, and used as the reactor for the regeneration method. Nitrogen purging was started: 0.8 h -1 Nitrogen was introduced into the reactor at a mass space velocity of , and the bed temperature of the reactor was raised to 200° C. and maintained at this temperature for 2 hours to complete nitrogen purging to obtain the first product.

[0052] (2) 0.5h -1 Steam was introduced into the reactor at a mass space velocity of , and the bed temperature of the reactor was raised to 300°C and kept at this temperature for 10 hours to complete the first steam purge. -1Water vapor is introduced into the reactor at a mass space velocity of , and the bed temperature of the reactor is raised to 400°C at a heating rate of 30°C / h. The temperature is maintained constant for 2 hours to complete the second water vapor purge and obtain the second product.

[0053] (3) Slowly introduce air into the steam pipeline connected to the reactor for calcination, and gradually increase the air flow rate according to the charring situation. During the entire calcination process, the bed temperature is 400°C and maintained for 5 hours. At this time, the contents of CO and CO2 in the calcination tail gas at the reactor outlet are analyzed. When the contents of both are less than 0.3 mol%, the calcination is considered complete, and the air is turned off to terminate it, and a third product is obtained.

[0054] (4) The temperature was lowered at a rate of 30°C / h. When the reactor inlet temperature reached 200°C, nitrogen was used for cooling until the reactor outlet temperature was less than 40°C. All valves were closed and the pressure was maintained at 0.3 MPa with N2. At the same time, the pre-sulfurization procedure was started.

[0055] (4-1) A nitrogen atmosphere is provided to the reactor by using a nitrogen replacement reaction system, and the oxygen content therein is reduced to less than 0.2 vol%, and a first pre-sulfurization is performed at a pressure of 3.0 MPa to obtain a fourth product; the first pre-sulfurization temperature is 130° C. and the time is 5 h.

[0056] (4-2) Switch nitrogen to H2, i.e., -1 Hydrogen was introduced into the reactor at a mass space velocity of 0.06 m / s to establish a circulation, and the fourth product was heated to 155°C. 3 / h flow rate of cracked mixed diesel (containing 2wt% dimethyl disulfide (DMDS), DMDS as a sulfiding agent) as a sulfiding agent, so that the hydrogen sulfide content in the hydrogen atmosphere increases; when the volume concentration of hydrogen sulfide in the hydrogen atmosphere reaches 0.50%, the fourth product is heated to 240°C, and the injection amount of cracked mixed diesel is gradually increased to 0.1m 3 / h, and after heating for 1.5h, the fifth product was obtained.

[0057] (4-3) The third presulfurization includes: heating the fifth product at 240°C for 3.5 hours; then heating the fifth product at 300°C for 10 hours at a heating rate of 10°C / h; continuing to heat the fifth product to 350°C and heating the fifth product at this temperature for 14 hours. During the third presulfurization process, presulfurized tail gas is generated at the reactor outlet. When the outlet sulfur concentration is greater than 20000ppm, the heating is terminated. After the heating is completed, the temperature is lowered at 20°C / h, with the first temperature lowered to 50°C and the second temperature lowered to 300°C. During the cooling process, cracked mixed diesel is continuously injected. After the temperature drops to the target temperature, the injection is stopped and the temperature is stabilized for another 5 hours. The presulfurization process is terminated, the reaction pipeline is cleaned, and a regenerated hydrogenation catalyst that can continue to be used for the hydrogenation reaction of the cracking C9+ component is obtained.

[0058] Example 3

[0059] A method for regenerating a spent hydrogenation catalyst:

[0060] The difference between this embodiment and embodiment 1 is only in step (1), specifically:

[0061] (1) The reactor used for the hydrogenation catalysis of the cracking C9+ components was shut down and switched to the regeneration condition, isolated from the process system, connected to the regeneration system, and used as the reactor for the regeneration method. Nitrogen purging was started: 0.5 h -1 Nitrogen was introduced into the reactor at a mass space velocity of , and the bed temperature of the reactor was raised to 150°C and maintained at this temperature for 3 hours to complete nitrogen purging to obtain the first product.

[0062] Example 4

[0063] A method for regenerating a spent hydrogenation catalyst:

[0064] The difference between this embodiment and embodiment 1 is only in step (1), specifically:

[0065] (1) The reactor used for the hydrogenation catalysis of the cracking C9+ components was shut down and switched to the regeneration condition, isolated from the process system, connected to the regeneration system, and used as the reactor for the regeneration method. Nitrogen purging was started: 0.5 h -1 Nitrogen was introduced into the reactor at a mass space velocity of , and the bed temperature of the reactor was raised to 250°C and maintained at this temperature for 1 hour to complete nitrogen purging to obtain the first product.

[0066] Example 5

[0067] A method for regenerating a spent hydrogenation catalyst:

[0068] The difference between this embodiment and embodiment 1 is only in step (2), specifically:

[0069] (2) 0.5h -1The reactor was purged with water vapor at a mass space velocity of 1.50 g / min, and the bed temperature of the reactor was lowered to 150°C and kept at this temperature for 14 hours to complete the first water vapor purge. -1 Water vapor is introduced into the reactor at a mass space velocity of , and the bed temperature of the reactor is raised to 450°C at a heating rate of 30°C / h. The temperature is maintained constant for 1 hour to complete the second water vapor purge and obtain the second product.

[0070] Example 6

[0071] A method for regenerating a spent hydrogenation catalyst:

[0072] The difference between this embodiment and embodiment 1 is only in step (2), specifically:

[0073] (2) 0.5h -1 The reactor was purged with steam at a mass space velocity of 1.5 mol / s and the bed temperature of the reactor was raised to 350°C and kept at this temperature for 8 hours to complete the first steam purge. -1 Water vapor is introduced into the reactor at a mass space velocity of , and the bed temperature of the reactor is maintained at 450° C. for 1 hour to complete the second water vapor purge and obtain the second product.

[0074] Example 7

[0075] A method for regenerating a spent hydrogenation catalyst:

[0076] The difference between this embodiment and embodiment 1 is only in step (3), specifically:

[0077] (3) Slowly introduce air into the steam pipeline connected to the reactor for calcination, and gradually increase the air flow rate according to the charring situation. During the entire calcination process, the bed temperature is 300°C and maintained for 6 hours. At this time, the contents of CO and CO2 in the calcination tail gas at the reactor outlet are analyzed, and the contents of the two are 0.4 mol% and 0.5 mol%, respectively. The air is turned off to terminate the process and obtain the third product.

[0078] Example 8

[0079] A method for regenerating a spent hydrogenation catalyst:

[0080] The difference between this embodiment and embodiment 1 is only in step (3), specifically:

[0081] (3) Slowly introduce air into the steam pipeline connected to the reactor for calcination, and gradually increase the air flow rate according to the charring situation. During the entire calcination process, the bed temperature is 500°C and maintained for 3 hours. At this time, the contents of CO and CO2 in the calcination tail gas at the reactor outlet are analyzed, and the contents of the two are 0.7 mol% and 0.8 mol%, respectively. The air is turned off to terminate the process and obtain the third product.

[0082] Example 9

[0083] A method for regenerating a spent hydrogenation catalyst:

[0084] The difference between this embodiment and embodiment 1 is only in step (4-1), specifically:

[0085] (4-1) A nitrogen atmosphere is provided to the reactor by using a nitrogen replacement reaction system, and the oxygen content therein is reduced to less than 0.2 vol%, and a first pre-sulfurization is performed at a pressure of 3.0 MPa to obtain a fourth product; the first pre-sulfurization temperature is 120° C. and the time is 6 h.

[0086] Example 10

[0087] A method for regenerating a spent hydrogenation catalyst:

[0088] The difference between this embodiment and embodiment 1 is only in step (4-1), specifically:

[0089] (4-1) A nitrogen atmosphere is provided to the reactor by using a nitrogen replacement reaction system, and the oxygen content therein is reduced to less than 0.2 vol%, and a first pre-sulfurization is performed at a pressure of 3.0 MPa to obtain a fourth product; the first pre-sulfurization temperature is 150° C. and the time is 3 h.

[0090] Embodiment 11

[0091] A method for regenerating a spent hydrogenation catalyst:

[0092] The difference between this embodiment and embodiment 1 is only in step (4-2), specifically:

[0093] (4-2) Switch nitrogen to H2, i.e., -1 Hydrogen was introduced into the reactor at a mass space velocity of 0.10 m / s to establish a circulation, and the fourth product was heated to 140°C. 3 / h flow rate of dimethyl disulfide (DMDS) as a sulfiding agent, so that the hydrogen sulfide content in the hydrogen atmosphere increases; when the volume concentration of hydrogen sulfide in the hydrogen atmosphere reaches 0.50%, the fourth product is heated to 250 ° C, and the injection amount of DMDS is gradually increased to 0.12m 3 / h, and after heating for 1.0h, the fifth product was obtained.

[0094] Example 12

[0095] A method for regenerating a spent hydrogenation catalyst:

[0096] The difference between this embodiment and embodiment 1 is only in step (4-2), specifically:

[0097] (4-2) Switch nitrogen to H2, i.e.,-1 Hydrogen was introduced into the reactor at a mass space velocity of 0.01 m / s to establish a circulation, and the fourth product was heated to 160°C. 3 / h flow rate of dimethyl disulfide (DMDS) as a sulfiding agent, so that the hydrogen sulfide content in the hydrogen atmosphere increases; when the volume concentration of hydrogen sulfide in the hydrogen atmosphere reaches 0.50%, the fourth product is heated to 220 ° C, and the injection amount of DMDS is gradually increased to 0.03m 3 / h, and after heating for 3.0h, the fifth product was obtained.

[0098] Example 13

[0099] A method for regenerating a spent hydrogenation catalyst:

[0100] The difference between this embodiment and embodiment 1 is only in step (4-3), specifically:

[0101] (4-3) The third presulfurization includes: heating the fifth product at 220°C for 4 hours; then heating the fifth product at 250°C for 14 hours at a heating rate of 10°C / h; and heating the fifth product at 400°C for 10 hours at this temperature. During the third presulfurization process, presulfurized tail gas is generated at the reactor outlet. When the outlet sulfur concentration is greater than 20,000 ppm, the heating is terminated.

[0102] Embodiment 14

[0103] A method for regenerating a spent hydrogenation catalyst:

[0104] The difference between this embodiment and embodiment 1 is only in step (4-3), specifically:

[0105] (4-3) The third presulfurization includes: heating the fifth product at 260°C for 2 hours; then heating the fifth product at 320°C for 8 hours at a heating rate of 10°C / h; and heating the fifth product at 330°C for 16 hours at this temperature. During the third presulfurization process, presulfurized tail gas is generated at the reactor outlet. When the outlet sulfur concentration is greater than 20,000 ppm, the heating is terminated.

[0106] Comparative Example 1

[0107] A method for regenerating a spent hydrogenation catalyst:

[0108] The only difference between this comparative example and Example 1 is that the nitrogen purge in step (1) is not performed, but water vapor is directly introduced into the reactor to perform the water vapor purge in step (2).

[0109] Comparative Example 2

[0110] A method for regenerating a spent hydrogenation catalyst:

[0111] The only difference between this comparative example and Example 1 is that the steam purge in step (2) is not performed, and instead air is directly introduced into the reactor after the first product is obtained to perform the calcination in step (3).

[0112] Comparative Example 3

[0113] A method for regenerating a spent hydrogenation catalyst:

[0114] The only difference between this comparative example and Example 1 is that the calcination in step (3) is not carried out, but nitrogen is directly introduced after the second product is obtained to carry out the pre-sulfurization procedure in step (4).

[0115] Comparative Example 4

[0116] A method for regenerating a spent hydrogenation catalyst:

[0117] The only difference between this comparative example and Example 1 is that in step (4-2), dimethyl disulfide ((CH3)2S2) is used as the sulfiding agent, and its injection flow rate is consistent with that of DMDS in Example 1.

[0118] Performance test method for regenerated hydrogenation catalyst

[0119] The regenerated hydrogenation catalyst obtained in each embodiment and comparative example is used as a catalyst for hydrogenation catalysis of cracking C9+ components, and is used in the hydrodesulfurization and deolefination reactions of cracking C9-C19 components (whose components are shown in Table 1). The specific reaction conditions are:

[0120] Two-stage fixed bed in series were used as hydrogenation reactors, with the first reactor temperature at 80°C, the second reactor temperature at 260°C, the reaction pressure at 2.8 MPa, and the hydrogen mass space velocity at 0.5 h -1 , the reaction time was set to 200 hours.

[0121] In the above reaction, the diene value of the first reaction export product, the sulfur content of the second reaction export product and the bromine value are shown in Table 2.

[0122] Table 1

[0123]

[0124] In this table, nP represents normal alkanes, iP represents isoalkanes, O represents olefins, N represents cycloalkanes, and A represents aromatic hydrocarbons.

[0125] Table 2

[0126]

[0127]

[0128] From the above description, it can be seen that the above-mentioned embodiment of the present invention realizes the efficient regeneration of the Ni-Mo metal sulfide waste catalyst used for the hydrogenation catalysis of the cracking C9+ component, and the obtained regenerated hydrogenation catalyst can show high catalytic activity and selectivity when used for the catalytic hydrogenation reaction of the cracking C9+ component.

[0129] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those described herein, for example.

[0130] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for regenerating a spent hydrogenation catalyst, characterized in that: include: Step S1, nitrogen purging: purging the spent hydrogenation catalyst with nitrogen to obtain a first product; Step S2, steam purging: purging the first product with steam to obtain a second product; Step S3, calcining: calcining the second product in an air atmosphere to obtain a third product; Step S4, pre-vulcanization: Step S4-1, performing a first presulfurization on the third product in a nitrogen atmosphere to obtain a fourth product; Step S4-2, in a hydrogen atmosphere, using dimethyl disulfide as a sulfiding agent, performing a second presulfurization on the fourth product to obtain a fifth product; Step S4-3, the fifth product is sequentially subjected to a third presulfurization and a cooling treatment to obtain a regenerated hydrogenation catalyst.

2. The method for regenerating a spent hydrogenation catalyst according to claim 1, characterized in that: The spent hydrogenation catalyst is a Ni-Mo metal sulfide spent catalyst used for two-stage hydrogenation catalysis of cracking C9+ components. The active components of the spent hydrogenation catalyst are Ni and / or Mo. Based on the total weight of the spent hydrogenation catalyst being 100%, the content of Ni is 3% to 20%, and the content of Mo is 15% to 30%.

3. The method for regenerating a spent hydrogenation catalyst according to claim 1 or 2, characterized in that: In step S1, the nitrogen mass space velocity used in the nitrogen purge is 0.5h -1 ~0.8h -1 The nitrogen purge temperature is 180°C to 200°C, and the time is 2h to 2.5h.

4. The method for regenerating a spent hydrogenation catalyst according to any one of claims 1 to 3, characterized in that: In step S2, the water vapor mass space velocity used for the water vapor purge is 0.5h -1 ~0.8h -1 , and the water vapor purge includes a first water vapor purge and a second water vapor purge performed sequentially; Preferably, the temperature of the first water vapor purge is 200°C to 300°C, and the time is 10h to 12h; And / or, the temperature of the second water vapor purge is 380° C. to 400° C., and the time is 2 h to 3 h.

5. The method for regenerating a spent hydrogenation catalyst according to any one of claims 1 to 4, characterized in that: In step S3, the calcination temperature is 350°C to 450°C and the calcination time is 4h to 5h; Preferably, the second product generates a calcination tail gas containing CO and CO2 during the calcination process, and the calcination is terminated when the contents of CO and CO2 in the calcination tail gas are both less than 0.3 mol%.

6. The method for regenerating a spent hydrogenation catalyst according to any one of claims 1 to 5, characterized in that: In step S4-1, the temperature of the first pre-sulfurization is 130°C to 140°C, and the time is 4h to 5h; Preferably, in step S4-1, the oxygen content of the nitrogen atmosphere is less than 0.2 vol%.

7. The method for regenerating a spent hydrogenation catalyst according to any one of claims 1 to 6, characterized in that: Step S4-2 includes: In the hydrogen atmosphere, the fourth product is heated to 150°C to 155°C at 0.05 m 3 / h~0.06m 3 / h injecting the sulfiding agent to increase the hydrogen sulfide content in the hydrogen atmosphere; When the volume concentration of hydrogen sulfide in the hydrogen atmosphere reaches 0.45% to 0.50%, the fourth product is heated to 230° C. to 240° C., and the injection flow rate of the sulfiding agent is increased to 0.08 m 3 / h~0.10m 3 / h, and heating for 1.5h to 2.0h to obtain the fifth product.

8. The method for regenerating a spent hydrogenation catalyst according to any one of claims 1 to 7, characterized in that: In step S4-3, the third pre-vulcanization includes one-stage heating, two-stage heating and three-stage heating performed in sequence, and: The temperature of the first stage heating is 240°C to 250°C, and the time is 3h to 3.5h; The temperature of the second stage heating is 280°C to 300°C, and the time is 10h to 12h; The temperature of the three-stage heating is 350° C. to 360° C., and the time is 12 h to 14 h.

9. The method for regenerating a spent hydrogenation catalyst according to any one of claims 1 to 8, characterized in that: In step S4-3, the fifth product generates presulfurized tail gas during the third presulfurization process, and when the sulfur concentration in the presulfurized tail gas is greater than 20000 ppm, the temperature reduction treatment is performed.

10. A hydrogenation catalyst for cracking C9+ components, characterized in that: The cracking C9+ component hydrogenation catalyst is a regenerated hydrogenation catalyst obtained by regenerating a waste catalyst produced during the hydrogenation of the cracking C9+ component using the method for regenerating a waste hydrogenation catalyst according to any one of claims 1 to 9.

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