Regeneration method of hydrogenation catalyst

Abstract

The invention discloses a hydrogenation catalyst regeneration method, which comprises: (1) impregnating an alkali metal poisoning hydrogenation catalyst with an organic phosphide solution, and carrying out drying (preferably vacuum drying) treatment; (2) carrying out high-temperature roasting treatment on the catalyst obtained in the step (1); and (3) washing and drying the catalyst obtained in the step (2) with a buffer solution to obtain the regenerated hydrogenation catalyst. The regeneration method can effectively remove alkali metal impurities contained in the catalyst and recover the activity of the catalyst.

Description

Technical Field

[0001] The present invention belongs to the technical field of catalyst regeneration, and relates to a regeneration method for a hydrogenation catalyst, in particular to a regeneration method for an abnormally deactivated hydrogenation catalyst. Background Art

[0002] Hydrogenation catalysts are crucial for the production of clean fuel oils and other chemical raw materials. During the hydrogenation process, catalysts may be deactivated due to various reasons, mainly including carbon deposition deactivation and metal impurity deposition deactivation. If deactivated catalysts are simply landfilled, it will not only pollute the environment but also waste resources. Therefore, the regeneration treatment of deactivated hydrogenation catalysts has attracted people's attention.

[0003] CN202111272120.3 discloses a method for recycling and reusing waste hydrogenation catalysts. The method includes the following steps: (1) roasting the waste hydrogenation catalyst in an oxygen-containing atmosphere; mixing the roasted product with an acid solution and heating under reflux; (2) adjusting the pH value of the reflux product obtained in step (1) to 3.5 - 4.5 using an organic amine and performing solid-liquid separation; the boiling point of the organic amine under normal pressure is greater than or equal to 100 °C; (3) using the liquid product filtered in step (2) as an impregnating solution to impregnate a carrier, and obtaining a regenerated hydrogenation catalyst through heat treatment.

[0004] CN201911361889.5 discloses a heavy oil hydrogenation treatment method. The heavy oil raw material contacts with hydrogen in a hydrogenation treatment reactor to complete the hydrogenation treatment process. The hydrogenation treatment reactor is filled with a regenerated agent obtained by regenerating a deactivated hydrogenation treatment catalyst. The regeneration process of the regenerated agent is as follows: carbon burning and desulfurization are performed on the deactivated hydrogenation treatment catalyst, then it is impregnated with an acidic solution containing a complexing agent, and then impregnated with an alkali solution and treated in an ammonia-containing atmosphere to effectively remove metal impurities such as nickel, vanadium, and iron.

[0005] The catalyst regeneration methods involved in the above patents are for catalysts deactivated due to conventional reasons such as carbon deposition and transition metal deposition. This kind of deactivation can often be adjusted by increasing the reaction temperature during the reaction process. Generally, when the reaction cycle is about to end and the reaction temperature can no longer be adjusted, the regeneration method in the prior art needs to be used to regenerate the catalyst. During the actual operation process, there is also a phenomenon of sudden deactivation of the catalyst that occurs within the normal operation cycle due to improper operating conditions and fluctuations in reaction raw materials. Regarding how to regenerate and whether it can be regenerated for this abnormally deactivated hydrogenation catalyst, the prior art does not give relevant solutions, and specific analysis needs to be made based on the deactivation reasons to provide relevant solutions. Summary of the Invention

[0006] The inventor once encountered a situation where a hydrogenation catalyst was deactivated abnormally. After the hydrotreating catalyst had been in operation for a short time, serious deactivation occurred. Even by increasing the temperature, the activity of the catalyst could not be restored, and the refining enterprise was forced to shut down for treatment. Through in-depth research, the inventor found that the cause of the catalyst deactivation was not carbon deposition and the deposition of transition metals. The main factor leading to the deactivation was the substantial increase in the content of alkali metals in the deactivated catalyst, which was caused by improper control of the raw materials during the industrial production process. Further research found that the reason for the rapid deactivation of the hydrogenation catalyst by alkali metal impurities was that the alkali metal impurities occupied the acidic sites on the catalyst surface.

[0007] Based on the above research results, the present invention proposes a regeneration method for a hydrogenation catalyst, mainly aiming at the deactivation of the hydrotreating catalyst caused by unconventional alkali metal deposition. The regeneration method can effectively remove the alkali metal impurities contained in the catalyst and restore the activity of the catalyst.

[0008] The first aspect of the present invention provides a regeneration method for a hydrogenation catalyst, including the following content: (1) Impregnating the alkali metal poisoned hydrogenation catalyst with an organophosphide solution, and then performing a drying (preferably vacuum drying) treatment; (2) Performing a high-temperature calcination treatment on the catalyst obtained in step (1); (3) Washing and drying the catalyst obtained in step (2) with a buffer solution to obtain a regenerated hydrogenation catalyst.

[0009] In the method of the present invention, the alkali metal poisoned hydrogenation catalyst in step (1) refers to a catalyst that is partially deactivated or fails to meet the reaction requirements due to the deposition of alkali metals during the hydrogenation process. The catalyst includes a carrier and an active metal component. The carrier is generally at least one of alumina, amorphous silica-alumina, and molecular sieve, and the active metal component is generally a metal of Group VIB and / or a metal of Group VIII. Among them, the metal of Group VIB is at least one of Mo and W, and the metal of Group VIII is at least one of Ni and Co.

[0010] In the method of the present invention, based on the mass of the alkali metal deposition deactivated catalyst after removing sulfur and carbon, the alkali metal content in the alkali metal poisoned hydrogenation catalyst is 0.2 wt% - 8.0 wt%, preferably 0.3 wt% - 5.0 wt%, more preferably 0.5 wt% - 3.0 wt%, and even more preferably 1 wt% - 2.0 wt%; the alkali metals include one or more of lithium, sodium, and potassium.

[0011] In the method of the present invention, in step (1), before the alkali metal poisoning hydrogenation catalyst is impregnated with the organic phosphide solution, the alkali metal poisoning hydrogenation catalyst may be subjected to a deoiling treatment; the deoiling treatment may be carried out by any of the means in the prior art that can remove the oil phase on the surface and in the pores of the deactivated catalyst, such as thermal hydrogen circulation and / or solvent extraction.

[0012] In the method of the present invention, the organic phosphide used in the organic phosphide solution in step (1) contains an ester group and / or an aromatic group, such as one or more of trimethyl phosphate, triethyl phosphate, tripropyl phosphate, tributyl phosphate, tripentyl phosphate, trihexyl phosphate, triheptyl phosphate, trioctyl phosphate, tricresyl phosphate, triphenyl phosphite, triphenylphosphine oxide, triphenyl phosphate and dibutyl phosphite; the solvent used in the organic phosphide solution is at least one of ethers, alcohols and ketones, such as one or more of diethyl ether, methanol, ethanol, propanol, butanol, ethylene glycol and acetone, preferably one or more of methanol, ethanol, propanol and acetone.

[0013] In the method of the present invention, the molar ratio of the organic phosphide (calculated as elemental phosphorus) contained in the organic phosphide solution in step (1) to the active metal component (calculated as elemental metal) contained in the alkali metal poisoning hydrogenation catalyst is 0.03-0.6, preferably 0.05-0.4; the active metal component includes Group VIB metals and / or Group VIII metals.

[0014] In the method of the present invention, the concentration of the organic phosphide solution in step (1) is 0.01-1.0 g / mL.

[0015] In the method of the present invention, the impregnation in step (1) is saturated impregnation or supersaturated impregnation, preferably supersaturated impregnation, and more preferably in supersaturated impregnation, the supersaturation degree is not less than 1.05, preferably 1.08-3.0.

[0016] In the method of the present invention, the drying treatment in step (1) is also well known to those skilled in the art, and the drying treatment temperature is 60-140° C. and the time is 2-6 hours.

[0017] In the method of the present invention, the temperature of the high temperature calcination treatment in step (2) is 700-1000°C, preferably 800-900°C, and the time is 1-3 hours; the high temperature calcination treatment is carried out in an oxygen-containing atmosphere, the oxygen content of the oxygen-containing atmosphere is 15v%-100v%, preferably air atmosphere.

[0018] In the method of the present invention, in step (3), the buffer solution is an aqueous solution containing an ammonium salt, and the concentration of ammonium ions is 0.003 - 0.04 mol / 100 g; the ammonium salt is one or more of ammonium carbonate, ammonium bicarbonate, triammonium phosphate, diammonium phosphate, monoammonium phosphate, ammonium acetate, and ammonium formate.

[0019] In the method of the present invention, in step (3), the buffer solution is slightly acidic / neutral with a pH value of 6.0 - 7.0. According to the different required pH values of the buffer solution, acetic acid and / or ammonia water can be used to adjust the pH value.

[0020] In the method of the present invention, the specific operation process of the washing in step (3) is as follows: spray the catalyst obtained in step (2) with the buffer solution, and repeat the above steps 1 - 10 times according to the difference in alkali metal content until the alkali metal content is lower than 0.1 wt%; wherein, the volume of the buffer solution used each time is 120% - 1000% of the saturated water absorption volume of the catalyst obtained in step (2).

[0021] In the method of the present invention, the drying treatment in step (3) can adopt conventional conditions in the art. For example, the drying temperature is 90 - 150 °C, and the drying time is 2 - 6 h.

[0022] In the method of the present invention, an active metal component can also be introduced into the catalyst in step (3). The specific process of introducing the active metal component is as follows: after washing and drying treatment, the active metal component is introduced into the obtained catalyst by an impregnation method; the impregnation method is saturated impregnation or supersaturated impregnation, preferably saturated impregnation; the mass of the introduced active metal component is the mass of the active metal lost during the washing process.

[0023] The second aspect of the present invention provides a regenerated hydrogenation catalyst obtained by the above method.

[0024] The third aspect of the present invention provides the application of the above regenerated hydrogenation catalyst in the hydrotreating reaction of distillate oil.

[0025] In the above application, the regenerated hydrogenation catalyst needs to be pre-sulfurized before the hydrotreating reaction of distillate oil. The pre-sulfurization technology can adopt methods well-known in the art, generally any one of dry sulfidation and wet sulfidation; specifically in the present invention, wet sulfidation can be adopted, and the specific operating conditions are as follows: sulfidation pressure 0.1 - 20 MPa, sulfidation temperature 230 - 550 °C, liquid hourly space velocity 0.5 - 10.0 h -1 , and the hydrogen-oil volume ratio is 50 - 2000:1. During the pre-sulfurization process, the metal heteropolyacid salts formed during the catalyst regeneration process will react and be converted into metal sulfides.

[0026] In the above application, the distillate oil is one or more of wax oil, diesel oil, kerosene, and gasoline.

[0027] In the above application, the operating conditions for the hydrotreating reaction of the distillate oil are as follows: the reaction temperature is 150 - 400 °C, the reaction pressure is 0.5 - 15 MPa, the liquid hourly space velocity is 0.3 - 10 h -1 , and the hydrogen-oil volume ratio is 100 - 1000.

[0028] Compared with the prior art, the present invention has the following advantages: 1. The present invention analyzes the phenomenon of abnormal deactivation of the hydrotreating catalyst caused by the deposition of alkali metals, and creatively proposes a regeneration method for the alkali metal-poisoned hydrotreating catalyst. In the method of the present invention, the alkali metal-poisoned hydrotreating catalyst is first impregnated with an organophosphide solution. During the subsequent high-temperature calcination process, the active metal components will complex with the organophosphide to form heteropolyacid salts (such as phosphomolybdic heteropolyacid salt, phosphotungstic heteropolyacid salt), reducing the concentration of the oxidized active metal components on the catalyst surface, thereby inhibiting the excessive aggregation of the oxidized active metal components during the high-temperature calcination process. Moreover, the synergistic effect of the impregnation with the organophosphide solution and the high-temperature calcination can solidify the active components, effectively reducing the loss of the active metal components during the process of washing and separating the alkali metals in the catalyst with the buffer solution. At the same time, during the high-temperature calcination process, the alkali metal impurities form water-soluble metal molybdates (such as sodium molybdate and / or sodium tungstate) with the Group VIB metal components (such as molybdenum and / or tungsten), and then are washed with a buffer solution to remove the alkali metals occupying the acidic sites of the catalyst and restore the activity of the catalyst.

[0029] 2. In the present invention, the organophosphide solution uses an organic solvent, and the organic solvent has better wetting performance for the carbon-containing catalyst, thus promoting the uniform impregnation of the organophosphide. Further, the supersaturated impregnation method is used to introduce the organophosphide solution, which is more conducive to the uniform impregnation of the organophosphide. Embodiment

[0030] The following further illustrates the solutions and effects of the present invention through examples, but does not constitute a limitation to the present invention.

[0031] In the present invention, during the supersaturated impregnation process, the supersaturation degree is the amount (mass) of the impregnating solution / the saturated water absorption amount (mass) * 100%.

[0032] In the present invention, the relative desulfurization activity is calculated according to the following formula: Relative desulfurization activity % = [1 / (S p ) 0.65 - 1 / (S f ) 0.65 / [1 / (S pr ) 0.65 - 1 / (S f ) 0.65 * 100% Where: S f is the sulfur content of the feedstock oil, mg / kg; S pr is the sulfur content of the hydrogenated product oil of the reference agent, mg / kg; S p is the sulfur content of the hydrogenated product oil of the fresh catalyst, mg / kg.

[0033] In the present invention, the alkali metal poisoned hydrotreating catalyst used in the examples and comparative examples is a deactivated hydrotreating catalyst obtained by applying a commercially available brand FHUDS-7 hydrotreating catalyst to a certain refinery. The sulfur content of this deactivated hydrotreating catalyst is 8.8 wt%, and the carbon content is 6.2 wt%. Based on the weight of the catalyst after removing sulfur and carbon, the alkali metal content (calculated as the oxide) is 1.5 wt%, the content of Group VIB metal Mo (calculated as the oxide) is 19 wt%, and the content of Group VIII metal Ni (calculated as the oxide) is 3 wt%.

[0034] In the present invention, the saturated water absorption of the alkali metal poisoned hydrotreating catalyst is 30 g water / 100 g catalyst.

[0035] In the present invention, the vacuum degree of vacuum drying is 3×10 -3 Pa.

[0036] Example 1 Take 117.6 g of the above-mentioned alkali metal poisoned hydrotreating catalyst. Dilute 3.12 g of triethyl phosphate with ethanol to 49.4 mL, and supersaturate it on the alkali metal poisoned hydrotreating catalyst, where the supersaturation is 1.4. After vacuum drying at 100 °C for 3 h, it is calcined at 800 °C in an air atmosphere for 2 h, and then left to cool to room temperature. Select 200 mL of ammonium phosphate / acetic acid buffer solution with a pH value of 6.5 and a concentration of 0.006 mol / 100 g to rinse the above catalyst. After three rinses, the alkali metal impurity content on the obtained catalyst is 0.04 wt%. After drying at 120 °C for 3 h, the measured Mo content of the catalyst (calculated as MoO 3 is 18 wt%, and the water absorption rate is 50 mL / 100 g. Then, it is saturatedly impregnated with an aqueous solution with a molybdenum content (calculated as molybdenum oxide) of 2 g / 100 mL, and a regenerated hydrotreating catalyst R-1 is obtained after drying at 120 °C for 3 h.

[0037] Example 2 Take 117.6 g of the above alkali metal poisoned hydrogenation catalyst. Dilute 19 g of tricresyl phosphate with ethanol to 60 mL, and supersaturate the impregnation on the alkali metal poisoned hydrogenation catalyst, where the supersaturation is 1.7. After vacuum drying at 120 °C for 3 h, place it in an air atmosphere and calcine at 900 °C for 2 h, and let it stand and cool to room temperature. Select 150 mL of ammonium bicarbonate / acetic acid buffer solution with a pH value of 6.8 and a concentration of 0.01 mol / 100 g to rinse the above catalyst. After four rinses, the alkali metal impurity content on the obtained catalyst is 0.03 wt%. After drying at 100 °C for 3 h, the Mo content (calculated as MoO 3 is measured to be 17.5 wt%, and the water absorption rate is 50 mL / 100 g. Then, saturate the impregnation with an aqueous solution with a molybdenum content (calculated as molybdenum oxide) of 3 g / 100 mL, and after drying at 110 °C for 3 h, obtain the regenerated hydrogenation catalyst R-2.

[0038] Example 3 Take 117.6 g of the above alkali metal poisoned hydrogenation catalyst. Dilute 6.8 g of dibutyl phosphite with ethanol to 84.7 mL, and supersaturate the impregnation on the alkali metal poisoned hydrogenation catalyst, where the supersaturation is 2.4. After vacuum drying at 80 °C for 3 h, place it in an air atmosphere and calcine at 750 °C for 2 h, and let it stand and cool to room temperature. Select 350 mL of ammonium formate / ammonia buffer solution with a pH value of 6.2 and a concentration of 0.02 mol / 100 g to rinse the above catalyst. After three rinses, the alkali metal impurity content on the obtained catalyst is 0.03 wt%. After drying at 110 °C for 3 h, the Mo content (calculated as MoO 3 is measured to be 17.8 wt%, and the water absorption rate is 50 mL / 100 g. Then, saturate the impregnation with an aqueous solution with a molybdenum content (calculated as molybdenum oxide) of 2.4 g / 100 mL, and after drying at 110 °C for 3 h, obtain the regenerated hydrogenation catalyst R-3.

[0039] Example 4 Take 117.6 g of the above alkali metal poisoned hydrogenation catalyst. Dilute 3.6 g of trimethyl phosphate with ethanol to 42.4 mL, and supersaturate the impregnation on the alkali metal poisoned hydrogenation catalyst, where the supersaturation is 1.2. After vacuum drying at 100 °C for 3 h, place it in an air atmosphere and calcine at 850 °C for 3 h, and let it stand and cool to room temperature. Select 250 mL of diammonium phosphate / acetic acid buffer solution with a pH value of 6.7 and a concentration of 0.03 mol / 100 g to rinse the above catalyst. After three rinses, the alkali metal impurity content on the obtained catalyst is 0.03 wt%. After drying at 100 °C for 3 h, the Mo content (calculated as MoO 3The content (calculated as molybdenum oxide) is 18.2 wt%, and the water absorption rate is 50 mL / 100 g. Then it is saturatedly impregnated with an aqueous solution containing 1.6 g / 100 mL of molybdenum content (calculated as molybdenum oxide), and after drying at 110 °C for 3 h, the regenerated hydrogenation catalyst R-4 is obtained.

[0040] Example 5 According to the preparation method of Example 1, but after washing to remove alkali metal impurities, the impregnation of active metals is not replenished. Take 117.6 g of the above alkali metal poisoned hydrogenation catalyst. Dilute 3.12 g of triethyl phosphate with ethanol to 49.4 mL, and supersaturate the impregnation on the alkali metal poisoned hydrogenation catalyst, where the supersaturation is 1.4. After vacuum drying at 100 °C for 3 h, it is calcined at 800 °C for 2 h in an air atmosphere, and left to cool to room temperature. Select 200 mL of ammonium phosphate / acetic acid buffer solution with a pH value of 6.5 and a concentration of 0.006 mol / 100 g to rinse the above catalyst. After three rinses, the alkali metal impurity content on the obtained catalyst is 0.04 wt%. After drying at 120 °C for 3 h, the regenerated hydrogenation catalyst R-5 is obtained.

[0041] Example 6 According to the preparation method of Example 2, but after washing to remove alkali metal impurities, the impregnation of active metals is not replenished. Take 117.6 g of the above alkali metal poisoned hydrogenation catalyst, dilute 19 g of tricresyl phosphate with ethanol to 60 mL, and supersaturate the impregnation on the alkali metal poisoned hydrogenation catalyst, where the supersaturation is 1.7. After vacuum drying at 120 °C for 3 h, it is calcined at 900 °C for 2 h in an air atmosphere, and left to cool to room temperature. Select 150 mL of ammonium bicarbonate / acetic acid buffer solution with a pH value of 6.8 and a concentration of 0.01 mol / 100 g to rinse the above catalyst. After four rinses, the alkali metal impurity content on the obtained catalyst is 0.03 wt%. After drying at 120 °C for 3 h, the regenerated hydrogenation catalyst R-6 is obtained.

[0042] Comparative Example 1 According to the preparation method of Example 1, but the alkali metal poisoned hydrogenation catalyst is not impregnated with organic phosphides and is directly calcined instead. Take 117.6 g of the above alkali metal poisoned hydrogenation catalyst, place it in an air atmosphere and calcine at 800 °C for 2 h, and leave it to cool to room temperature. Select 200 mL of ammonium phosphate / acetic acid buffer solution with a pH value of 6.5 and a concentration of 0.006 mol / 100 g to rinse the above catalyst. After three rinses, the alkali metal impurity content on the obtained catalyst is 0.20 wt%. After drying at 120 °C for 3 h, the Mo content (calculated as MoO 3 ) of the catalyst is 14 wt%, and the water absorption rate is 50 mL / 100 g. It is saturatedly impregnated with an aqueous solution containing 10 g / 100 mL of molybdenum content (calculated as molybdenum oxide), and after drying at 120 °C for 3 h, the regenerated hydrogenation catalyst D-1 is obtained.

[0043] Comparative Example 2 According to the preparation method of Example 1, but after impregnating with the organic phosphide, it is calcined at low temperature. Take 117.6 g of the above alkali metal poisoned hydrogenation catalyst. Dilute 3.12 g of triethyl phosphate with ethanol to 49.4 mL, and supersaturate the impregnation on the alkali metal poisoned hydrogenation catalyst, where the supersaturation is 1.4. After vacuum drying at 100 °C for 3 h, it is calcined at 500 °C in an air atmosphere for 2 h, and left to cool to room temperature. Select 200 mL of ammonium triphosphate / acetic acid buffer solution with a pH value of 6.5 and a concentration of 0.006 mol / 100 g to rinse the above catalyst. After three rinses, the alkali metal impurity content on the catalyst is 0.17 wt%. After drying at 120 °C for 3 h, the Mo content (calculated as MoO 3 is) 13 wt%, and the water absorption rate is 50 mL / 100 g. Saturatedly impregnate an aqueous solution with a molybdenum content (calculated as molybdenum oxide) of 12 g / 100 mL, and after drying at 120 °C for 3 h, a regenerated hydrogenation catalyst D-2 is obtained.

[0044] Comparative Example 3 According to the preparation method of Example 1, but use dilute nitric acid with a pH value of 3 to rinse the catalyst to remove alkali metal impurities. Take 117.6 g of the above alkali metal poisoned hydrogenation catalyst. Dilute 3.12 g of triethyl phosphate with ethanol to 49.4 mL, and supersaturate the impregnation on the alkali metal poisoned hydrogenation catalyst, where the supersaturation is 1.4. After vacuum drying at 100 °C for 3 h, it is calcined at 500 °C in an air atmosphere for 2 h, and left to cool to room temperature. Select 200 mL of dilute nitric acid solution with a pH value of 3 to rinse the above catalyst. After three rinses, the alkali metal impurity content on the catalyst is 0.03 wt%. After drying at 120 °C for 3 h, the Mo content (calculated as MoO 3 is) 13.5 wt%, and the water absorption rate is 50 mL / 100 g. Saturatedly impregnate an aqueous solution with a molybdenum content (calculated as molybdenum oxide) of 11 g / 100 mL, and after drying at 120 °C for 3 h, a regenerated hydrogenation catalyst D-3 is obtained.

[0045] Example 6 Carry out an activity evaluation test on the catalysts obtained in the examples and comparative examples in a 10 mL reaction device. The feedstock oil is straight-run diesel from the third normal distillation line with a sulfur content of 1.9 wt%, a nitrogen content of 290 ng / μL, and an end boiling point of 367 °C. Before the start of the reaction, the catalyst needs to be pre-sulfurized. The sulfurizing agent is straight-run diesel from the first normal distillation line added with 1.5 v% DMDS, and the sulfurization operating conditions are: sulfurization pressure 6.4 MPa, liquid hourly space velocity 1.5 h -1, the hydrogen-oil volume ratio is 400:1. The catalyst in the reactor is completely wetted at 140°C, and then heated to 320°C at a heating rate of 1°C / min and kept at a constant temperature for 10 h to complete sulfidation. The reaction operating conditions are as follows: reaction pressure 6.4 MPa, reaction temperature 360°C, liquid hourly space velocity 1.5 h -1 , the hydrogen-oil volume ratio is 400:1. After the initial activity is stabilized for 24 h, the properties of the product are analyzed. The properties and relative desulfurization activities of the catalysts are listed in Table 1.

[0046] Table 1 Properties and desulfurization activities of catalysts in examples and comparative examples

[0047] *Based on the fresh catalyst, its desulfurization activity is set at 100%.

Claims

1. A method for regenerating a hydrogenation catalyst, Features: It includes the following: (1) impregnating an alkali metal poisoning hydrogenation catalyst with an organic phosphide solution, and then drying (preferably vacuum drying); (2) subjecting the catalyst obtained in step (1) to high temperature calcination; (3) The catalyst obtained in step (2) is washed and dried with a buffer solution to obtain a regenerated hydrogenation catalyst.

2. The method according to claim 1, Features: The alkali metal poisoned hydrogenation catalyst in step (1) refers to a catalyst that is partially deactivated or fails to meet the reaction requirements due to alkali metal deposition during the hydrogenation process.

3. The method according to claim 1, Features: In step (1), based on the mass of the alkali metal deposited deactivated catalyst after the removal of sulfur and carbon, the alkali metal content in the alkali metal poisoned hydrogenation catalyst is 0.2wt%-8.0wt%, preferably 0.3wt%-5.0wt%, more preferably 0.5wt%-3.0wt%, and even more preferably 1wt%-2.0wt%; the alkali metal includes one or more of lithium, sodium and potassium.

4. The method according to claim 1, Features: In step (1), before the alkali metal poisoning hydrogenation catalyst is impregnated with the organic phosphide solution, the alkali metal poisoning hydrogenation catalyst is subjected to a deoiling treatment; the deoiling treatment adopts any one of hot hydrogen circulation and solvent extraction.

5. The method according to claim 1, Features: The organic phosphide used in the organic phosphide solution in step (1) is one or more of trimethyl phosphate, triethyl phosphate, tripropyl phosphate, tributyl phosphate, tripentyl phosphate, trihexyl phosphate, triheptyl phosphate, trioctyl phosphate, tricresyl phosphate, triphenyl phosphite, triphenylphosphine oxide, triphenyl phosphate and dibutyl phosphite; the solvent used in the organic phosphide solution is at least one of ethers, alcohols and ketones, such as one or more of diethyl ether, methanol, ethanol, propanol, butanol, ethylene glycol and acetone, preferably one or more of methanol, ethanol, propanol and acetone.

6. The method according to claim 1, Features: The molar ratio of the organic phosphide (calculated as elemental phosphorus) contained in the organic phosphide solution in step (1) to the active metal component (calculated as elemental metal) contained in the alkali metal poisoning hydrogenation catalyst is 0.03-0.6, preferably 0.05-0.4; the active metal component comprises a Group VIB metal and / or a Group VIII metal.

7. The method according to claim 1, Features: The concentration of the organic phosphide solution in step (1) is 0.01-1.0 g / mL.

8. The method according to claim 1, Features: The impregnation in step (1) is saturated impregnation or supersaturated impregnation, preferably supersaturated impregnation, and more preferably, in supersaturated impregnation, the supersaturation degree is not less than 1.05, preferably 1.08-3.

0.

9. The method according to claim 1, Features: The drying treatment temperature in step (1) is 60-140°C and the time is 2-6 hours.

10. The method according to claim 1, characterized in that: in step (2), the temperature of the high-temperature calcination treatment is 700 to 1000 °C, preferably 800 to 900 °C, and the time is 1 to 3 h; the high-temperature calcination treatment is carried out in an oxygen-containing atmosphere, and the oxygen content of the oxygen-containing atmosphere is 15 v% to 100 v%, preferably an air atmosphere.

11. The method according to claim 1, characterized in that: in step (3), the buffer solution is an aqueous solution containing an ammonium salt, and the concentration of ammonium ions therein is 0.003 to 0.04 mol / 100 g; the ammonium salt is one or more of ammonium carbonate, ammonium bicarbonate, triammonium phosphate, diammonium phosphate, monoammonium phosphate, ammonium acetate, and ammonium formate.

12. The method according to claim 1, characterized in that: in step (3), the buffer solution is slightly acidic / neutral, and the pH value is 6.0 to 7.

0.

13. The method according to claim 1, characterized in that: the specific operation process of the washing in step (3) is as follows: the catalyst obtained in step (2) is sprayed with a buffer solution, and according to the difference in alkali metal content, the above steps 1 to 10 are repeated until the alkali metal content is lower than 0.1 wt%; wherein, the volume of the buffer solution used each time is 120% to 1000% of the saturated water absorption volume of the catalyst obtained in step (2).

14. The method according to claim 1, characterized in that: in step (3), the drying temperature is 90 to 150 °C, and the drying time is 2 to 6 h.

15. The method according to claim 1, characterized in that: in the method of the present invention, an active metal component is further introduced into the catalyst in step (3), and the specific process of introducing the active metal component is as follows: after washing and drying treatments, the active metal component is introduced into the obtained catalyst by an impregnation method; the impregnation method is saturated impregnation or supersaturated impregnation, preferably saturated impregnation; the mass of the introduced active metal component is the mass of the active metal lost during the washing process.

16. A regenerated hydrogenation catalyst obtained by the method according to any one of claims 1 to 15.

17. Use of the regenerated hydrogenation catalyst according to claim 16 in the hydrotreating of distillate oil.

Images