Modified hydrofining catalyst, process for its preparation and use, acid-modified composite support and process for its preparation

Abstract

The present disclosure relates to a modified hydrofining catalyst, a preparation method and application thereof, and an acid-modified composite carrier and a preparation method thereof. The modified hydrofining catalyst comprises 50-80 wt% of a carrier and 18-50 wt% of an active metal component, based on the total weight of the modified hydrofining catalyst, the active metal component being in the form of metal oxides; the carrier comprises an acid-modified biomass charcoal-coated alumina composite carrier; and the active metal component comprises a first active metal component and a second active metal component, the first active metal component being selected from one or more of Group VIII metal elements, and the second active metal component being selected from one or more of Group VIB metal elements. The present disclosure simply and cheaply prepares the acid-modified biomass charcoal-coated alumina composite carrier, effectively regulates the surface properties of the composite carrier, and solves the problem of loss of surface acid centers of the carrier.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of petroleum chemical industry, in particular, to a modified hydrofining catalyst and a preparation method and application thereof, and an acid-modified composite carrier and a preparation method thereof. BACKGROUND

[0002] The hydrodesulfurization process is a key technology for producing clean oil products, and the core of which lies in the development of supported sulfided Co(Ni)Mo(W) catalysts. The active phase structure of the supported Co(Ni)Mo(W) catalysts is divided into two types, i.e., Co(Ni)-Mo(W)-S-I type with single-layer stacking structure and Co(Ni)-Mo(W)-S-II type with multi-layer stacking structure. Since the active sites of the catalysts are unsaturated vacancies or sulfur vacancies on the surface of the active metal in the sulfided state, the Co(Ni)-Mo(W)-S-II type active phase is more likely to expose the active sites of the catalysts, and thus the activity thereof is generally higher than that of the Co(Ni)-Mo(W)-S-I type active phase.

[0003] The formation of the active phase structure is closely related to the optimization and selection of the carrier. For the traditional industrial catalysts with γ-Al2O3 as the carrier, the active metal is prone to strong interaction with the abundant hydroxyl groups on the surface of the γ-Al2O3 carrier to form M-O-Al structure, thereby generating the Co(Ni)-Mo(W)-S-I type active phase with single-layer stacking structure, reducing the sulfidation degree of the catalysts, reducing the active sites, and reducing the activity. Therefore, how to effectively weaken the interaction force between the metal and the γ-Al2O3 carrier in the Co(Ni)Mo(W) catalysts to form the Co(Ni)-Mo(W)-S-II type active phase with multi-layer stacking structure, thereby improving the activity of the catalysts, is an important research direction for the current efforts.

[0004] Carbon materials are inert materials on the surface, and the interaction force between the carbon materials and the active metal is weaker than that between the traditional γ-Al2O3 carrier and the active metal, which is beneficial to the sulfidation of the active metal and the formation of the Co(Ni)-Mo(W)-S-II type active phase. Therefore, the carbon materials are used to modify the traditional γ-Al2O3 carrier to improve the hydrodesulfurization activity of the catalysts, which has great development prospects.

[0005] CN 100406122C discloses a preparation method of an Al2O3 carrier with large pore size, concentrated pore distribution, and good strength by using rice husk powder, peanut shell powder, and coconut shell powder as a pore expander, and the carrier is applied to the hydrogenation process of heavy oil and residual oil, and finally the hydrodesulfurization rate of the catalyst is only improved by about 4%, which is poor. This is mainly because the patent only uses crop stem shell powder as a hard template to realize the pore expansion of the Al2O3 carrier by removing through calcination, and fails to realize the regulation of the surface properties of the carrier.

[0006] CN 101733151A discloses a method for preparing a carbon-containing γ-Al2O3 carrier by using organic carboxylic acid and organic carboxylic acid ammonium salt as carbon precursors, introducing the carbon precursors into a shaped γ-Al2O3 carrier by impregnation, and then calcining under inert atmosphere, and further using the carbon-containing γ-Al2O3 carrier as a carrier for preparing a hydrofining catalyst. The results show that the desulfurization rate of the catalyst is increased by about 6% by using the modified γ-Al2O3 carrier. The method uses expensive organic carboxylic acid and organic carboxylic acid ammonium salt as carbon precursors, which is high in cost. At the same time, although the carbon-modified γ-Al2O3 carrier is beneficial to the sulfidation of active metals, it also covers the acid sites on the surface of the carrier, which is not conducive to the adsorption and activation of sulfide molecules, thereby making it difficult for the catalyst to effectively remove sulfides with steric hindrance effect (the main problem faced by clean diesel production).

[0007] In order to solve the problem of the loss of acid centers on the surface of the carbon-modified γ-Al2O3 carrier, CN 107159302B and CN 105688978B introduce expensive molecular sieves and other non-metallic additives B, F, P, etc. to modify the hydrofining catalyst while using organic alcohols, sugars, organic acids, etc. as carbon sources and adopting a two-stage activation method to prepare the carbon-modified γ-Al2O3 carrier, which achieves certain effect.

[0008] In summary, in the existing reports of carbon material modified hydrodesulfurization catalysts, the precursors and methods used for preparing the carbon materials are relatively complex and high in cost. Therefore, one of the key problems to be solved is to seek a cheaper way to prepare the carbon-modified γ-Al2O3 carrier for modifying the hydrodesulfurization catalyst. At the same time, how to effectively solve the problem of the loss of acid centers on the surface of the carbon-modified γ-Al2O3 carrier is also one of the key technical problems to be solved in the application of the carbon-modified γ-Al2O3 carrier in the field of hydrofining catalysts. SUMMARY

[0009] The purpose of the present disclosure is to provide a modified hydrofining catalyst, a preparation method and application thereof, and an acid-modified composite carrier and a preparation method thereof, which can simply and cheaply prepare an acid-modified biomass carbon-coated alumina composite carrier and effectively control the surface properties of the composite carrier to solve the problem of the loss of acid centers on the surface of the carrier.

[0010] In order to achieve the above-mentioned objectives, the first aspect of the present disclosure provides a modified hydrotreating catalyst, which comprises, based on the total weight of the modified hydrotreating catalyst, 50 to 80 weight percent of a carrier and 18 to 50 weight percent of an active metal component, wherein the active metal component is in the form of a metal oxide; the carrier comprises an acid-modified biochar-coated alumina composite carrier; the active metal component comprises a first active metal component and a second active metal component, wherein the first active metal component is selected from one or more metal elements of Group VIII; and the second active metal component is selected from one or more metal elements of Group VIB.

[0011] Optionally, the total acid content of the acid-modified biochar-coated alumina composite support measured by pyridine infrared at 150° C. is 150 to 200 μmol / g;

[0012] Preferably, the acid-modified biochar-coated alumina composite support contains Br(Ⅱ) acid; preferably, the Br(Ⅱ) acid content of the acid-modified biochar-coated alumina composite support measured by pyridine infrared at 150° C. is greater than 20 μmol / g;

[0013] Optionally, the BET specific surface area of ​​the acid-modified biochar-coated alumina composite carrier is 250 to 400 m 2 / g.

[0014] Optionally, the modified hydrorefining catalyst is a sulfurized modified hydrorefining catalyst, and the sulfurized modified hydrorefining catalyst further comprises SO4 2- Species; preferably, the modified hydrorefining catalyst after sulfidation is measured by X-ray photoelectron spectroscopy S spectrum, SO4 2- The species content is 5-30%.

[0015] Optionally, based on the total weight of the carrier, the carrier comprises 0.1 to 15 weight % of biochar and 85 to 99.9 weight % of alumina;

[0016] Preferably, based on the total weight of the modified hydrotreating catalyst, the content of the first active metal component is 3 to 10 weight %; the content of the second active metal component is 15 to 40 weight %.

[0017] Optionally, the first active metal component is selected from one or both of Ni and Co; and the second active metal component is selected from one or both of Mo and W.

[0018] A second aspect of the present disclosure provides a method for preparing an acid-modified biochar-coated alumina composite support, comprising the following steps:

[0019] S1, mixing a biomass raw material, an alumina precursor and an acidic additive to obtain a composite carrier precursor;

[0020] S2, performing a first calcination treatment on the composite support precursor to obtain a composite support intermediate;

[0021] S3, subjecting the composite carrier intermediate to hydrothermal treatment.

[0022] Optionally, in step S1, based on the total weight of the biomass raw material and the alumina precursor, the content of the biomass raw material is 5 to 40 weight %; the content of the alumina precursor is 60 to 95 weight %;

[0023] Preferably, the amount of the acidic auxiliary agent added is 0.1 to 10% by weight based on the total weight of the biomass raw material and the alumina precursor.

[0024] Optionally, in step S1, the biomass raw material is selected from one or more of corn stalks, wheat stalks, rice stalks and sorghum stalks;

[0025] The alumina precursor is selected from one or more of pseudo-boehmite, aluminum hydroxide and aluminum nitrate; preferably pseudo-boehmite;

[0026] The acidic auxiliary agent includes a first acidic auxiliary agent and an optional second acidic auxiliary agent; the first acidic auxiliary agent includes sulfuric acid; the second acidic auxiliary agent is selected from one or more of nitric acid, phosphoric acid, citric acid, oxalic acid, tartaric acid, oxalic acid, malic acid, adipic acid and ethylenediaminetetraacetic acid; preferably, the weight ratio of the first acidic auxiliary agent to the second acidic auxiliary agent is 1:0 to 4, preferably 1:0.5 to 3.

[0027] Optionally, the method further includes:

[0028] The biomass raw material is subjected to a first drying treatment, a crushing treatment, and a sieving treatment to obtain a biomass powder with a particle size of less than 60 mesh, and then mixed with the alumina precursor and the acidic auxiliary agent and ground to a particle size of less than 200 mesh to obtain a composite carrier precursor;

[0029] Optionally, the conditions of the first drying treatment include: drying at 60-150° C. for 12-36 hours;

[0030] Optionally, the pulverization treatment conditions include: grinding at 1000 to 10000 r / min for 12 to 36 hours.

[0031] Optionally, in step S2, the conditions of the first calcination treatment include: a calcination temperature of 300-700° C., a calcination time of 3-8 hours; and a calcination atmosphere of one or more of air, nitrogen, oxygen, argon, and water vapor;

[0032] Preferably, before the first calcination treatment, the composite support precursor is dried at 60-150° C. for 4-15 hours.

[0033] Optionally, in step S3, the conditions of the hydrothermal treatment include: a hydrothermal temperature of 150 to 350° C., a hydrothermal time of 2 to 8 hours; and an atmosphere of the hydrothermal treatment selected from one or more of oxygen, nitrogen, ammonia, and carbon dioxide;

[0034] Preferably, step S3 further comprises: adding deionized water dropwise to the composite carrier intermediate until the composite carrier intermediate reaches a saturated water absorption state, and then performing the hydrothermal treatment;

[0035] Optionally, the method further comprises: cooling the hydrothermal treatment product and then drying it at 60 to 150° C. for 4 to 15 hours.

[0036] The third aspect of the present disclosure provides an acid-modified biochar-coated alumina composite carrier prepared according to the method of the second aspect.

[0037] A fourth aspect of the present disclosure provides a method for preparing a modified hydrotreating catalyst, comprising the following steps:

[0038] An active metal precursor, a carrier and an auxiliary agent are mixed, and then subjected to a molding treatment and a second calcination treatment; wherein the carrier comprises the acid-modified biochar-coated alumina composite carrier described in the third aspect of the present disclosure; wherein the active metal precursor comprises a first active metal precursor and a second active metal precursor; the first active metal precursor is selected from one or more of the Group VIII metal precursors; and the second active metal precursor is selected from one or more of the Group VIB metal precursors.

[0039] Optionally, the method includes: impregnating the support with the solution of the active metal precursor;

[0040] Optionally, the first active metal precursor is selected from one or more of a nickel metal precursor and a cobalt metal precursor; preferably, the nickel metal precursor is selected from one or more of nickel nitrate, basic nickel carbonate and nickel sulfate, preferably basic nickel carbonate and / or nickel nitrate; the cobalt metal precursor is selected from one or more of cobalt sulfate, cobalt carbonate, cobalt oxalate and cobalt nitrate, preferably cobalt nitrate and / or cobalt oxalate;

[0041] The second active metal precursor is selected from one or more of a molybdenum metal precursor and a tungsten metal precursor; preferably, the molybdenum metal precursor is selected from one or more of sodium molybdate, ammonium molybdate, molybdenum chloride and molybdic acid, preferably ammonium molybdate; the tungsten metal precursor is selected from one or more of ammonium metatungstate, phosphotungstic acid and silicotungstic acid, preferably ammonium metatungstate and / or phosphotungstic acid;

[0042] Preferably, the weight ratio of the first active metal precursor: the second active metal precursor: the acid-modified biochar-coated alumina composite carrier is 0.1-0.7:0.2-0.9:1.

[0043] Optionally, the conditions of the second calcination treatment include: a calcination temperature of 300-600° C., a calcination time of 3-6 hours; and a calcination atmosphere of one or more of air, nitrogen, oxygen, argon, and water vapor;

[0044] Optionally, before the second calcination treatment, the product obtained by the molding treatment is dried at 80-160° C. for 4-12 hours.

[0045] The fifth aspect of the present disclosure provides a modified hydrotreating catalyst prepared according to the method of the fourth aspect of the present disclosure.

[0046] A sixth aspect of the present disclosure provides use of the modified hydrotreating catalyst of the first aspect or the fifth aspect in a feedstock oil hydrotreating reaction.

[0047] Optionally, the method comprises the following steps: contacting the crude oil with a modified hydrorefining catalyst under hydrogenation conditions to carry out a hydrorefining reaction;

[0048] Optionally, the conditions of the hydrofining reaction include: reaction temperature of 260-380°C; hydrogen pressure of 2-10 MPa; hydrogen-oil volume ratio of 200-800:1; raw oil mass space velocity of 0.5-6h -1 ;

[0049] Optionally, the feedstock oil is selected from gasoline and / or diesel fractions;

[0050] Preferably, the method further comprises: performing a sulfurization treatment on the modified hydrotreating catalyst before performing the hydrotreating reaction.

[0051] Through the above technical solutions, the present disclosure provides a modified hydrorefining catalyst and its preparation method and application, an acid-modified composite carrier and its preparation method. The present disclosure uses cheap biomass raw materials to prepare a biomass carbon-coated alumina composite carrier with a "tree root"-like structure, and the composite carrier is acid-modified. While having a high specific surface area and pore volume, the regulation of the acid sites on the surface of the composite carrier is achieved; the present disclosure uses at least one metal component of Group VIII and at least one metal component of Group VIB as an active metal component to obtain a modified hydrorefining catalyst, which has a good catalytic effect in hydrorefining reactions such as desulfurization. The acid-modified biomass carbon-coated alumina composite carrier provided by the present disclosure can effectively regulate the interaction force between the active metal and the carrier in the catalyst, modify the microscopic stacking structure of the metal active phase, and significantly improve the activity of the catalyst.

[0052] Other features and advantages of the present disclosure will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] The accompanying drawings are used to provide a further understanding of the present disclosure and constitute a part of the specification. Together with the following detailed description, they are used to explain the present disclosure but do not constitute a limitation of the present disclosure. In the accompanying drawings:

[0054] Figure 1 This is a scanning electron microscope photograph of the acid-modified biochar-coated alumina composite support prepared in Example 1. DETAILED DESCRIPTION

[0055] The following describes the specific embodiments of the present disclosure in detail. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present disclosure and are not intended to limit the present disclosure.

[0056] The first aspect of the present disclosure provides a modified hydrotreating catalyst, which comprises, based on the total weight of the modified hydrotreating catalyst, 50 to 80 weight percent of a carrier and 18 to 50 weight percent of an active metal component, wherein the active metal component is in the form of a metal oxide; the carrier comprises an acid-modified biochar-coated alumina composite carrier; the active metal component comprises a first active metal component and a second active metal component, wherein the first active metal component is selected from one or more metal elements of Group VIII; and the second active metal component is selected from one or more metal elements of Group VIB.

[0057] The present disclosure provides a modified hydrorefining catalyst, which utilizes inexpensive biomass raw materials to prepare a biomass carbon-coated alumina composite carrier having a "tree root"-like structure. The composite carrier is acid-modified, and while having a high specific surface area and pore volume, the acid sites on the surface of the composite carrier are regulated. The present disclosure uses at least one metal component from Group VIII and at least one metal component from Group VIB as active metal components to obtain a modified hydrorefining catalyst, which has a good catalytic effect in hydrorefining reactions such as desulfurization. The acid-modified biomass carbon-coated alumina composite carrier provided by the present disclosure can effectively regulate the interaction force between the active metal and the carrier in the catalyst, modify the microscopic stacking structure of the metal active phase, and significantly improve the activity of the catalyst.

[0058] In the present disclosure, the symbol “@” indicates that the substance before the symbol is coated on the surface of the substance after the symbol, that is, “acid-modified biomass carbon coated alumina composite carrier” can be represented by “acid-modified biomass carbon@alumina composite carrier” or “acid-modified biomass C@alumina composite carrier”.

[0059] In the present disclosure, biochar refers to a product obtained by processing biomass raw materials through a process including roasting, etc. Biomass raw materials include common raw materials such as corn stalks, wheat stalks, rice stalks and sorghum stalks.

[0060] In one embodiment, the support comprises 0.1-15% by weight of biochar and 85-99.9% by weight of alumina, based on the total weight of the support. In this disclosure, the alumina and biochar contents in the support are determined by thermogravimetric analysis. Using a support having the composition described in this embodiment, the modified hydrorefining catalyst can achieve enhanced catalytic performance.

[0061] In one embodiment, based on the total weight of the modified hydrotreating catalyst, the content of the first active metal component is 3 to 10 weight %; and the content of the second active metal component is 15 to 40 weight %.

[0062] In a specific embodiment, the first active metal component is selected from one or both of nickel (Ni) and cobalt (Co); the second active metal component is selected from one or both of molybdenum (Mo) and tungsten (W).

[0063] In one embodiment, the total acid content of the acid-modified biochar-coated alumina composite support measured by pyridine infrared at 150°C is 150-200 μmol / g; the BET specific surface area of ​​the acid-modified biochar-coated alumina composite support is 250-400 m 2 The composite carrier provided by the present invention has a lower acid content than ordinary γ-Al2O3, indicating that the introduction of biochar on the surface of the composite carrier of the present invention achieves effective regulation of the surface properties of the carrier and increases the BET specific surface area of ​​the carrier.

[0064] In a preferred embodiment, the acid-modified biochar-coated alumina composite support contains Br(II) acid. Preferably, the Br(II) acid content of the acid-modified biochar-coated alumina composite support is greater than 20 μmol / g as measured by pyridine infrared spectroscopy at 150°C. The acid-modified biochar@Al2O3 composite support provided herein has Br(II) acid centers on its surface, resulting in a higher concentration of active hydrogen species on the catalyst surface.

[0065] In a preferred embodiment, the modified hydrorefining catalyst is a sulfurized modified hydrorefining catalyst, and the sulfurized modified hydrorefining catalyst further comprises SO4 2- Species; preferably, the modified hydrorefining catalyst after sulfidation is measured by X-ray photoelectron spectroscopy (XPS) S spectrum, SO4 2- The content of the species is 5-30%. The composite carrier provided by the present disclosure contains SO4 2-The appearance of can further polarize the thiol (-SH) on the surface of the active metal, promote the formation of sulfur vacancies on the catalyst surface and modify the electronic structure of the active metal. 2- The calculation method of the content of SO4 is as follows: In the S spectrum of the X-ray photoelectron spectroscopy (XPS) of the sample, 2- Content = SO4 2- / (SO4 2- +S 2- +S2 - )×100%. In the above calculation method, the ion symbol represents the peak area of ​​the characteristic peak of the species in the XPS spectrum, such as SO4 2- Indicates SO4 2- The peak area of ​​the characteristic peak of a species in the XPS spectrum.

[0066] A second aspect of the present disclosure provides a method for preparing an acid-modified biochar-coated alumina composite support, comprising the following steps:

[0067] S1, mixing a biomass raw material, an alumina precursor and an acidic additive to obtain a composite carrier precursor;

[0068] S2, performing a first calcination treatment on the composite support precursor to obtain a composite support intermediate;

[0069] S3, subjecting the composite carrier intermediate to hydrothermal treatment.

[0070] In the present disclosure, the biomass raw material, alumina precursor and an acidic auxiliary agent are mixed and then subjected to a first calcination treatment, which allows the biochar and alumina to interact during the calcination process to form an intermediate of a biochar-coated alumina composite carrier. The addition of the acidic auxiliary agent has the effect of modifying the surface properties of the carrier; the composite carrier intermediate obtained by calcination is then subjected to a hydrothermal treatment. The hydrothermal treatment environment can be used to improve the properties of the interface between biochar and alumina, and promote the formation of a "tree root"-like surface structure.

[0071] In a preferred embodiment, in step S1, based on the total weight of the biomass raw material and the alumina precursor, the content of the biomass raw material is 5 to 40 weight %; the content of the alumina precursor is 60 to 95 weight %;

[0072] Preferably, the amount of the acidic additive added is 0.1 to 10% by weight based on the total weight of the biomass raw material and the alumina precursor. The composite carrier prepared by reacting according to the raw material ratio and content in this embodiment has better performance.

[0073] In one embodiment, the biomass raw material is selected from one or more of corn stalks, wheat stalks, rice stalks and sorghum stalks;

[0074] The alumina precursor is selected from one or more of pseudo-boehmite, aluminum hydroxide and aluminum nitrate; preferably pseudo-boehmite.

[0075] In a preferred embodiment, the acidic auxiliary agent includes a first acidic auxiliary agent and an optional second acidic auxiliary agent; the first acidic auxiliary agent includes sulfuric acid; and the second acidic auxiliary agent is selected from one or more of nitric acid, phosphoric acid, citric acid, oxalic acid, tartaric acid, oxalic acid, malic acid, adipic acid, and ethylenediaminetetraacetic acid. Preferably, the weight ratio of the first acidic auxiliary agent to the second acidic auxiliary agent is 1:0 to 4, preferably 1:0.5 to 3. In the present disclosure, sulfuric acid is used as the first acidic auxiliary agent and the optional second acidic auxiliary agent to prepare a composite support containing sulfate species, thereby improving the catalytic performance of the final catalyst.

[0076] In a specific embodiment, the method further includes:

[0077] The biomass raw material is subjected to a first drying treatment, a crushing treatment, and a sieving treatment to obtain a biomass powder with a particle size of less than 60 mesh, and then mixed with the alumina precursor and the acidic auxiliary agent and ground to a particle size of less than 200 mesh to obtain a composite carrier precursor;

[0078] Optionally, the conditions of the first drying treatment include: drying at 60-150° C. for 12-36 hours;

[0079] Optionally, the pulverization treatment conditions include: grinding at 1000 to 10000 r / min for 12 to 36 hours.

[0080] In a preferred embodiment, in step S2, the conditions of the first calcination treatment include: a calcination temperature of 300-700° C., a calcination time of 3-8 hours; and a calcination atmosphere of one or more of air, nitrogen, oxygen, argon, and water vapor;

[0081] Preferably, before the first calcination treatment, the composite support precursor is dried at 60-150° C. for 4-15 hours.

[0082] In one embodiment, in step S3, the conditions of the hydrothermal treatment include: a hydrothermal temperature of 150 to 350° C., a hydrothermal time of 2 to 8 hours; and an atmosphere of the hydrothermal treatment selected from one or more of oxygen, nitrogen, ammonia, and carbon dioxide.

[0083] In a specific embodiment, step S3 further comprises: adding deionized water dropwise to the composite carrier intermediate until the composite carrier intermediate reaches a saturated water absorption state, and then performing the hydrothermal treatment;

[0084] Optionally, the method further comprises: cooling the hydrothermal treatment product and then drying it at 60 to 150° C. for 4 to 15 hours.

[0085] The devices used in the preparation process of the composite carrier disclosed in the present invention are all conventional devices in the art.

[0086] The third aspect of the present disclosure provides an acid-modified biochar-coated alumina composite carrier prepared according to the method of the second aspect of the present disclosure.

[0087] A fourth aspect of the present disclosure provides a method for preparing a modified hydrotreating catalyst, comprising the following steps:

[0088] An active metal precursor, a carrier and an auxiliary agent are mixed, and then subjected to a molding treatment and a second calcination treatment; wherein the carrier comprises the acid-modified biochar-coated alumina composite carrier described in the third aspect of the present disclosure; wherein the active metal precursor comprises a first active metal precursor and a second active metal precursor; the first active metal precursor is selected from one or more of the Group VIII metal precursors; and the second active metal precursor is selected from one or more of the Group VIB metal precursors.

[0089] In the present disclosure, the mixing and molding processes can adopt conventional processes and conditions in the art.

[0090] In a preferred embodiment, the weight ratio of the first active metal precursor: the second active metal precursor: the acid-modified biochar-coated alumina composite support is 0.1-0.7: 0.2-0.9: 1. Preparing a catalyst according to this weight ratio can produce a hydrorefining catalyst with improved catalytic performance.

[0091] In one embodiment, the method includes: impregnating the solution of the active metal precursor with the support; the conditions of the impregnation treatment may include: an impregnation time of 0.5 to 4 hours, preferably 0.5 to 2.5 hours.

[0092] In a specific embodiment, the first active metal precursor is selected from one or more of a nickel metal precursor and a cobalt metal precursor; preferably, the nickel metal precursor is selected from one or more of nickel nitrate, basic nickel carbonate and nickel sulfate, preferably basic nickel carbonate and / or nickel nitrate; the cobalt metal precursor is selected from one or more of cobalt sulfate, cobalt carbonate, cobalt oxalate and cobalt nitrate, preferably cobalt nitrate and / or cobalt oxalate;

[0093] The second active metal precursor is selected from one or more of a molybdenum metal precursor and a tungsten metal precursor; preferably, the molybdenum metal precursor is selected from one or more of sodium molybdate, ammonium molybdate, molybdenum chloride and molybdic acid, preferably ammonium molybdate; the tungsten metal precursor is selected from one or more of ammonium metatungstate, phosphotungstic acid and silicotungstic acid, preferably ammonium metatungstate and / or phosphotungstic acid.

[0094] In the present disclosure, the shaping treatment includes one of extrusion molding and inverse molding, preferably the extrusion molding treatment. The specific process and device of the extrusion molding are well known to those skilled in the art.

[0095] In one embodiment, the auxiliary agent includes an extrusion aid and a binder;

[0096] The extrusion aid is selected from one or more of starch, sesbania powder, polyethylene glycol and methyl cellulose; preferably, the addition amount of the extrusion aid is 1-10 wt%, preferably 3-8 wt%, based on the total weight of the components;

[0097] The binder is selected from one or more of nitric acid, citric acid, tartaric acid, oxalic acid and ethanedioic acid; preferably, the addition amount of the binder is 1-10 wt%, preferably 3-8 wt%, based on the total weight of the components.

[0098] The reagents used in the present disclosure can be purchased through conventional channels or prepared by known methods.

[0099] In one specific embodiment, the shape of the catalyst product obtained by the shaping treatment can be strip-shaped, clover-shaped, granular or tooth ball-shaped.

[0100] In one embodiment, the conditions of the second calcination treatment include a calcination temperature of 300-600°C, a calcination time of 3-6h; and a calcination atmosphere of one or more of air, nitrogen, oxygen, argon and water vapor;

[0101] Optionally, before the second calcination treatment, the product obtained by the shaping treatment is dried at 80-160°C for 4-12h.

[0102] The fifth aspect of the present disclosure provides a modified hydrofining catalyst prepared by the method according to the fourth aspect of the present disclosure.

[0103] The sixth aspect of the present disclosure provides the use of the modified hydrofining catalyst of the first aspect or the fifth aspect in a hydrofining reaction of a raw oil.

[0104] In one embodiment, the method includes the following steps: under hydrogenation conditions, contacting a raw oil with a modified hydrofining catalyst to perform a hydrofining reaction;

[0105] Optionally, the conditions of the hydrofining reaction include a reaction temperature of 260-380°C; a hydrogen pressure of 2-10 MPa; a hydrogen / oil volume ratio of 200-800:1; and a raw oil mass space velocity of 0.5-6 h -1 .

[0106] ​Optionally, the conditions for the hydrofining reaction include: a reaction temperature of 260 to 380°C; a hydrogen pressure of 2 to 10 MPa; a hydrogen to oil volume ratio of 200 to 800:1; and a feed oil mass space velocity of 0.5 to 6 h -1 ;

[0107] Optionally, the feedstock oil is selected from gasoline and / or diesel fractions.

[0108] In a specific embodiment, the method further includes: performing a sulfurization treatment on the modified hydrorefining catalyst before performing the hydrorefining reaction.

[0109] In a preferred embodiment, the temperature of the sulfurization treatment is 200-500°C, the pressure is 0.1-10 MPa, the time of the sulfurization treatment is 1-60 hours, and the liquid hourly mass space velocity is 0.1-20 hours. -1 , the volume ratio of hydrogen to oil is 100-800.

[0110] The present disclosure is further described in detail below through examples. The raw materials used in the examples are all commercially available. The performance tests were performed using instruments commonly used in the field.

[0111] The methods for determining and calculating the total content of the oxides of the active component metals in the catalyst are well known in the art, specifically including XRF and ICP methods.

[0112] The test method for the acid content of the acid-modified biochar-coated alumina composite support includes the pyridine infrared method.

[0113] The test method for the sulfate content in the hydrotreating catalyst after sulfidation treatment is XPS.

[0114] The test method for the content of biomass char and alumina in the composite support includes thermogravimetric analysis.

[0115] The BET specific surface area of ​​the sample was determined by nitrogen physical adsorption at low temperature.

[0116] In the following examples and comparative examples, “C@Al2O3” means carbon-coated alumina.

[0117] Example 1

[0118] Preparation of acid-modified biochar-coated alumina composite support:

[0119] (1) Take an appropriate amount of wheat stalk and corn stalk respectively, dry at 70°C for 24h, then crush and sieve. Then, take 15g of wheat stalk powder and 15g of corn stalk powder with particle size less than 100 mesh respectively, mix with 70g of commercially available pseudo-boehmite, 4g of tartaric acid and 4g of sulfuric acid, and then put them into a ball mill to grind at a speed of 4000r / min for 18h to obtain a composite carrier precursor; the content of biomass raw material is 30wt% based on the total weight of biomass raw material and alumina precursor; the content of alumina precursor is 70wt%; the addition amount of acidic additive is 8wt%; the weight ratio of the first acidic additive (sulfuric acid) and the second acidic additive (tartaric acid) is 1:1;

[0120] (2) Dry the composite carrier precursor at 100°C for 8h, then calcine at 400°C in 15vol% O2 / Ar atmosphere for 5h, and then naturally cool to obtain a C@Al2O3 composite carrier intermediate;

[0121] (3) Add deionized water to the composite carrier intermediate dropwise until it is saturated with water, then transfer it to an autoclave and replace the autoclave with nitrogen for 3 times, then hydrothermally treat it at 200°C for 4h, then naturally cool, and then dry at 80°C for 6h to obtain a biomass C@Al2O3 composite carrier, which is marked as SC-1, and its properties are shown in Table 1.

[0122] Preparation of the catalyst:

[0123] (4) Take 5.84g of nickel nitrate and 9.77g of ammonium metatungstate, dissolve them in 62.31g of deionized water to prepare a mixed impregnation solution. Drop the mixed impregnation solution onto 20.10g of the above-mentioned C@Al2O3 composite carrier dropwise and mix uniformly (the weight ratio of the first active metal precursor: the second active metal precursor: the biomass carbon-coated alumina composite carrier is 0.29:0.49:1), then dry at 120°C for 6h, and then mix uniformly with 0.4g of methyl cellulose, 0.2g of tianq powder, 0.3g of nitric acid, 0.4g of citric acid and an appropriate amount of deionized water, and then extrude into a strip-shaped catalyst with a diameter of 1.5mm;

[0124] (5) Dry the prepared strip-shaped catalyst at 100°C for 8h, then calcine at 450°C for 6h, and then naturally cool to obtain the hydrofining catalyst, which is marked as AC-1.

[0125] It is measured that the total content of nickel oxide and tungsten oxide in the AC-1 catalyst is 33.0wt% based on the total weight of the catalyst, wherein the content of the first active metal component (nickel oxide) is 5.0wt%, and the content of the second active metal component (tungsten oxide) is 28.0wt%; the content of the carrier is 67.0wt%.

[0126] The scanning electron microscope photo of the acid-modified biochar-coated alumina composite support SC-1 prepared in this example is shown in FIG. Figure 1 As shown by Figure 1 It can be seen that the composite carrier prepared by the method provided by the present disclosure has a large number of "tree-root-like" structures (which can also be regarded as "grid" structures).

[0127] Example 2

[0128] Preparation of acid-modified biochar-coated alumina composite support:

[0129] (1) Take appropriate amounts of corn stalks and rice stalks, dry them at 70°C for 24 hours, crush them with a grinder and sieve them. Then, take 15g corn stalks and 20g rice stalks powder with a particle size less than 100 mesh, mix them with 65g commercially available pseudo-boehmite, 3g sulfuric acid, 1g nitric acid and 3g citric acid, place them in a ball mill and grind them at a speed of 4000 rpm for 18 hours to obtain a composite carrier precursor; based on the total weight of the biomass raw material and the alumina precursor, the content of the biomass raw material is 35% by weight; the content of the alumina precursor is 65% by weight; the amount of the acidic additive added is 7% by weight; the weight ratio of the first acidic additive (sulfuric acid) to the second acidic additive (nitric acid and citric acid) is 1:1.33;

[0130] (2) The composite support precursor was dried at 100°C for 8 h, and then calcined at 400°C in a 10 vol% O2 / Ar atmosphere for 5 h, and then naturally cooled to obtain a C@Al2O3 composite support intermediate;

[0131] (3) Deionized water was added dropwise to the composite carrier intermediate until it reached a saturated water absorption state, and then the intermediate was transferred to a hydrothermal reactor. The hydrothermal reactor was replaced with carbon dioxide three times, and the intermediate was hydrothermally treated at 220 °C for 4 h. After natural cooling, the intermediate was dried at 80 °C for 6 h to obtain a biomass C@Al2O3 composite carrier, which was labeled as SC-2. Its properties are shown in Table 1.

[0132] Preparation of catalyst:

[0133] (4) 5.83 g of cobalt nitrate and 10.67 g of ammonium molybdate were dissolved in 61.38 g of deionized water to prepare a mixed impregnation solution. The mixed impregnation solution was added dropwise onto 19.80 g of the C@Al2O3 composite support and mixed evenly (the weight ratio of the first active metal precursor: the second active metal precursor: the biochar-coated alumina composite support was 0.29:0.54:1), and then dried at 120 ° C for 4 hours. Then, the mixture was evenly mixed with 0.7 g of polyethylene glycol, 0.4 g of nitric acid, 0.3 g of citric acid and an appropriate amount of deionized water, and extruded into a strip catalyst with a diameter of 1.5 mm;

[0134] (5) The obtained strip catalyst was dried at 120° C. for 7 h, and then calcined at 500° C. for 4 h. After natural cooling, the hydrorefining catalyst was obtained, which was labeled as AC-2.

[0135] The AC-2 catalyst was found to have a total content of cobalt oxide and molybdenum oxide of 34.0 wt%, based on the total weight of the catalyst, of which the content of the first active metal component (cobalt oxide) was 5.0 wt%, and the content of the second active metal component (molybdenum oxide) was 29.0 wt%; and the carrier content was 66.0 wt%.

[0136] Example 3

[0137] Preparation of acid-modified biochar-coated alumina composite support:

[0138] (1) Take an appropriate amount of rice straw and dry it at 70°C for 24 hours, then crush it with a grinder and sieve it. Then, take 10g of biomass powder with a particle size of less than 100 mesh, mix it with 90g of commercially available pseudo-boehmite, 2g of sulfuric acid, 1g of phosphoric acid and 2g of oxalic acid, and place it in a ball mill and grind it at a speed of 4000 rpm for 18 hours to obtain a composite carrier precursor; based on the total weight of the biomass raw material and the alumina precursor, the content of the biomass raw material is 10% by weight; the content of the alumina precursor is 90% by weight; the amount of the acidic additive added is 5% by weight; the weight ratio of the first acidic additive (sulfuric acid) to the second acidic additive (phosphoric acid and oxalic acid) is 1:1.5;

[0139] (2) The composite support precursor was dried at 100°C for 8 h, and then calcined at 400°C in a 5 vol% O2 / N2 atmosphere for 4 h, and then naturally cooled to obtain a C@Al2O3 composite support intermediate;

[0140] (3) Deionized water was added dropwise to the composite carrier intermediate until it was saturated with water, and then the intermediate was transferred to a hydrothermal reactor. The hydrothermal reactor was replaced with ammonia three times, and the intermediate was hydrothermally treated at 200 °C for 4 h. After natural cooling, the intermediate was dried at 80 °C for 6 h to obtain a biomass C@Al2O3 composite carrier, which was labeled as SC-3. Its properties are shown in Table 1.

[0141] Preparation of catalyst:

[0142] (4) 4.67 g of nickel nitrate, 1.47 g of molybdenum nitrate and 9.42 g of ammonium metatungstate were dissolved in 60.45 g of deionized water to prepare a mixed impregnation solution. The mixed impregnation solution was added dropwise onto 19.50 g of the above-mentioned C@Al2O3 composite support and mixed evenly (the weight ratio of the first active metal precursor: the second active metal precursor: the biochar-coated alumina composite support was 0.24:0.56:1), and then dried at 90 ° C for 6 hours. Then, it was evenly mixed with 0.6 g of sesbania powder, 0.4 g of nitric acid, 0.3 g of citric acid and an appropriate amount of deionized water, and extruded into a clover-shaped catalyst with a diameter of 1.5 mm;

[0143] (5) The obtained clover-shaped catalyst was dried at 100° C. for 8 h, and then calcined at 450° C. for 5 h. After natural cooling, the hydrotreating catalyst was obtained, which was labeled as AC-3.

[0144] It was determined that the total content of nickel oxide, molybdenum oxide, and tungsten oxide in the AC-3 catalyst was 35.0 wt%, based on the total weight of the catalyst; the content of the first active metal component (nickel oxide) was 4.0 wt%; the content of the second active metal component was 31.0 wt% (of which the content of molybdenum oxide was 4.0 wt% and the content of tungsten oxide was 27.0 wt%); and the carrier content was 65.0 wt%.

[0145] Example 4

[0146] This comparative example refers to the preparation method in Example 1, except that sulfuric acid is replaced with tartaric acid of the same mass. The rest of the process is the same as in Example 1. The prepared carrier is marked as SC-4, and the prepared hydrorefining catalyst is marked as AC-4.

[0147] The AC-4 catalyst was found to have a total content of nickel oxide and tungsten oxide of 33.0 wt%, based on the total weight of the catalyst, of which the content of the first active metal component (nickel oxide) was 5.0 wt%, and the content of the second active metal component (tungsten oxide) was 28.0 wt%; and the carrier content was 67.0 wt%.

[0148] Example 5

[0149] This example refers to the preparation method in Example 1, and the difference from Example 1 is that the preparation conditions are changed, specifically including:

[0150] The first calcination temperature is 800°C and the calcination time is 3h;

[0151] The temperature of the hydrothermal reaction was 400 °C and the hydrothermal time was 2 h;

[0152] The second calcination temperature is 700°C and the calcination time is 4h;

[0153] The remaining process was the same as in Example 1. The prepared carrier was marked as SC-5, and the prepared hydrorefining catalyst was marked as AC-5.

[0154] It was measured that the total content of nickel oxide and tungsten oxide in the AC-5 catalyst was 33.0 weight percent, based on the total weight of the catalyst, of which the content of the first active metal component (nickel oxide) was 5.0 weight percent and the content of the second active metal component (tungsten oxide) was 28.0 weight percent; the carrier content was 67.0 weight percent.

[0155] Comparative Example 1

[0156] (1) Take 100g of pseudo-boehmite, calcine it at 500℃ in air atmosphere for 4h, and then cool it naturally to obtain γ-Al2O3 carrier.

[0157] (2) 5.84 g of nickel nitrate and 9.77 g of ammonium metatungstate were dissolved in 87.76 g of deionized water to prepare a mixed impregnation solution. The mixed impregnation solution was added dropwise onto 28.31 g of γ-Al2O3 and mixed evenly. The mixture was then dried at 120°C for 6 hours. The mixture was then mixed evenly with 0.4 g of methyl cellulose, 0.2 g of Tianqing powder, 0.3 g of nitric acid, 0.4 g of citric acid, and an appropriate amount of deionized water, and extruded into a strip catalyst with a diameter of 1.5 mm.

[0158] (3) The obtained strip catalyst was dried at 100° C. for 8 h, and then calcined at 450° C. for 6 h. After natural cooling, the hydrorefining catalyst was obtained, which was marked as R-1.

[0159] The total content of nickel oxide and tungsten oxide in the R-1 catalyst was measured to be 33.0 wt % based on the total weight of the catalyst, of which the content of nickel oxide was 5.0 wt %; the content of tungsten oxide was 28.0 wt %; and the content of the carrier was 67.0 wt %.

[0160] Comparative Example 2

[0161] (1) Take 100g of pseudo-boehmite, calcine it at 500℃ in air atmosphere for 4h, and then cool it naturally to obtain γ-Al2O3 carrier.

[0162] (2) 5.83 g of cobalt nitrate and 10.67 g of ammonium molybdate were dissolved in 86.45 g of deionized water to prepare a mixed impregnation solution. The mixed impregnation solution was added dropwise onto 27.89 g of γ-Al2O3 and mixed evenly. The mixture was then dried at 120°C for 4 hours. The mixture was then mixed evenly with 0.7 g of polyethylene glycol, 0.4 g of nitric acid, 0.3 g of citric acid, and an appropriate amount of deionized water, and extruded into a catalyst strip with a diameter of 1.5 mm.

[0163] (3) The obtained strip catalyst was dried at 120° C. for 7 h, and then calcined at 500° C. for 4 h. After natural cooling, the hydrorefining catalyst was obtained, which was marked as R-2.

[0164] The total content of cobalt oxide and molybdenum oxide in the R-2 catalyst was measured to be 34.0 wt % based on the total weight of the catalyst, of which the content of cobalt oxide was 5.0 wt % and the content of molybdenum oxide was 29.0 wt %; and the carrier content was 66.0 wt %.

[0165] Comparative Example 3

[0166] (1) Take 100g of pseudo-boehmite, calcine it at 500℃ in air atmosphere for 4h, and then cool it naturally to obtain γ-Al2O3 carrier.

[0167] (2) 4.67 g of nickel nitrate, 1.47 g of molybdenum nitrate, and 9.42 g of ammonium metatungstate were dissolved in 85.14 g of deionized water to prepare a mixed impregnation solution. The mixed impregnation solution was added dropwise onto 27.40 g of γ-Al2O3 and mixed uniformly. The mixture was then dried at 90°C for 6 hours. The mixture was then mixed uniformly with 0.6 g of sesbania powder, 0.4 g of nitric acid, 0.3 g of citric acid, and an appropriate amount of deionized water, and extruded into a clover-shaped catalyst with a diameter of 1.5 mm.

[0168] (3) The obtained clover-shaped catalyst was dried at 100° C. for 8 h, and then calcined at 450° C. for 5 h. After natural cooling, the hydrorefining catalyst was obtained, which was marked as R-3.

[0169] It was measured that in the R-3 catalyst, the total content of nickel oxide, molybdenum oxide and tungsten oxide was 35.0 weight % based on the total weight of the catalyst; the content of nickel oxide was 4.0 weight %; the content of molybdenum oxide was 4.0 weight %; the content of tungsten oxide was 27.0 weight %; and the carrier content was 65.0 weight %.

[0170] Comparative Example 4

[0171] This comparative example refers to the preparation method in Example 1, and the difference from Example 1 is that the quality of the raw materials added is changed, specifically including:

[0172] Preparation of acid-modified biochar-coated alumina composite support:

[0173] (1) Take an appropriate amount of wheat stalk and corn stalk respectively, dry at 70°C for 24h, then crush and sieve. Then, take 40g of wheat stalk powder and 30g of corn stalk powder with particle size less than 100 mesh, mix with 30g of commercially available pseudo-boehmite, 3g of tartaric acid and 20g of sulfuric acid, and then put them into a ball mill to grind at a speed of 4000r / min for 18h to obtain a composite carrier precursor; the content of biomass raw material is 70wt% based on the total weight of biomass raw material and alumina precursor; the content of alumina precursor is 30wt%; the addition amount of acidic additive is 23wt%; the weight ratio of the first acidic additive (sulfuric acid) and the second acidic additive (tartaric acid) is 1:0.15;

[0174] (2) Dry the composite carrier precursor at 100°C for 8h, then calcine at 400°C in an atmosphere of 15vol% O2 / Ar for 5h, and then naturally cool to obtain a C@Al2O3 composite carrier intermediate;

[0175] (3) Add deionized water to the composite carrier intermediate dropwise until it is saturated with water, then transfer it to an autoclave and replace the autoclave with nitrogen for 3 times, and then hydrothermally treat it at 200°C for 4h, and then naturally cool, and then dry it at 80°C for 6h to obtain a biomass C@Al2O3 composite carrier, which is marked as DC-4, and its properties are shown in Table 1.

[0176] Preparation of the catalyst:

[0177] (4) Dissolve 17.25g of nickel nitrate and 17.44g of ammonium metatungstate in 24.15g of deionized water to prepare a mixed impregnation solution. Drop the mixed impregnation solution dropwise onto 10.50g of the above-mentioned C@Al2O3 composite carrier and mix uniformly (the weight ratio of the first active metal precursor: the second active metal precursor: the biomass charcoal-coated alumina composite carrier is 1.64:1.66:1), then dry it at 120°C for 6h, and then mix it uniformly with 0.4g of methyl cellulose, 0.2g of tianq powder, 0.3g of nitric acid, 0.4g of citric acid and an appropriate amount of deionized water, and then extrude it into a strip-shaped catalyst with a diameter of 1.5mm;

[0178] (5) Dry the prepared strip-shaped catalyst at 100°C for 8h, and then calcine it at 450°C for 6h, and then naturally cool to obtain the hydrogenation refining catalyst, which is marked as R-4.

[0179] It is measured that the total content of nickel oxide and tungsten oxide in the R-4 catalyst is 65wt% based on the total weight of the catalyst, among which the content of nickel oxide is 15wt% and the content of tungsten oxide is 50wt%; the content of the carrier is 65.0wt%.

[0180] The biomass char content, alumina content, total acid content measured by 150°C pyridine infrared, B acid content, and BET specific surface area data of the carrier products obtained in the above examples and comparative examples (acid-modified biomass C@Al2O3 composite carrier and conventional γ-Al2O3 carrier) are listed in the following Table 1.

[0181] Table 1

[0182]

[0183] As can be seen from Table 1, compared with traditional γ-Al2O3 supports (Comparative Examples 1 to 3), the modified biomass C@Al2O3 composite supports SC-1 to SC-4 prepared using the method provided by the present disclosure have higher specific surface areas and lower acid content, and Brønsted acid centers appear on the support surface. Both the higher specific surface area and the appropriate Brønsted acid centers are beneficial to improving the activity of the catalyst. In particular, the formation of Brønsted acid centers allows the catalyst surface to have more active hydrogen species, which is beneficial for the catalyst to remove sulfur-containing compounds with steric hindrance effects, and the removal of such sulfides is more conducive to the production of clean diesel.

[0184] Reaction test example

[0185] This test example provides a test experiment of hydrogenation treatment of the catalysts prepared in the above examples and comparative examples.

[0186] The catalyst of the embodiment and the comparative example catalyst were compared respectively, and the reaction process was as follows: presulfurization was carried out before application to make the catalyst have better hydrogenation effect. Presulfurization was carried out using a 10mL high temperature and high pressure hydrogenation micro-reaction device. It was a wet in-situ presulfurization, i.e., wet presulfurization was used. After presulfurization, the catalyst was not unloaded and hydrogenation reaction was continued directly in the reactor. The presulfurized oil was a n-decane solution containing 5 wt% CS2. The presulfurization temperature was 320°C, the pressure was 4MPa, and the liquid hourly mass space velocity was 1.5h -1 , the hydrogen-to-oil volume ratio is 300.

[0187] The hydrotreatment of this test example was carried out using a 10mL high-temperature and high-pressure hydrogenation microreactor. 4,6-DMDBT is a typical representative component of sulfides that are difficult to remove in gasoline and diesel fractions. Therefore, this test example uses a 4,6-DMDBT / n-decane solution with a sulfur content of 1000ppm as an evaluation raw material to compare the performance of the hydrotreating catalyst. The raw material is pumped in using a plunger pump, and the oil sample after the reaction is cooled in a high separator and collected and analyzed in a low separator. The temperature of the hydrotreatment is 300°C, the pressure is 4MPa, and the liquid hourly space velocity (mass space velocity) is 8.7h -1 The hydrogen-to-oil volume ratio was 600. The evaluation results of the catalyst after hydrotreatment are shown in Table 2.

[0188] The sulfur content of the reactants and products was detected by ultraviolet fluorescence detection and chemiluminescence detection methods.

[0189] Desulfurization rate (mol %) = (raw material sulfur content - product sulfur content) / raw material sulfur content × 100%.

[0190] SO4 2- Content = SO4 2- / (SO4 2- +S 2- +S2 - )×100%. The ion symbol represents the peak area of ​​the characteristic peak of the species in the XPS spectrum, such as SO4 2- Indicates SO4 2- The peak area of ​​the characteristic peak of a species in the XPS spectrum.

[0191] Table 2

[0192]

[0193]

[0194] It can be seen from the data in Table 2 that compared with the catalysts R1 to R3 prepared in Comparative Examples 1 to 3 (using conventional γ-Al2O3 as a carrier), the hydrodesulfurization catalysts AC-1 to AC-3 prepared using the acid-modified biomass C@Al2O3 composite material provided by the present disclosure as a carrier (compared with the examples and comparative examples with the same active metal components) have higher hydrodesulfurization activity and can effectively improve the catalyst's removal effect on sulfides with steric hindrance effects. This is mainly due to two reasons. First, the introduction of biomass carbon effectively modifies the surface properties of the carrier Al2O3, increases the specific surface area of ​​the carrier, and forms many "root-like" species on the surface of the carrier (see Appendix). Figure 1 ), so that the active metal can be better dispersed on the surface of the carrier; secondly, acid modification of biomass makes the surface of biomass C@Al2O3 composite carrier have B acid center, so that the catalyst surface has more active hydrogen species, and SO4 2- The presence of further polarizes the thiol (-SH) groups on the active metal surface, promoting the formation of sulfur vacancies on the catalyst surface and modifying the electronic structure of the active metal. Ultimately, the combined action of these two factors leads to the cleavage of the C-S bond, thereby enhancing the activity of the catalyst.

[0195] Compared with the catalyst R-4 prepared in comparative example 4 (the raw material addition ratio and catalyst composition are not within the scope of this disclosure), the catalysts AC-1 to AC-5 prepared according to the method provided in this disclosure have higher hydrodesulfurization activity and higher desulfurization rate.

[0196] Comparing Example 1 with Examples 4 to 5, Example 4 only used the second acidic auxiliary agent and did not add sulfuric acid. The preparation conditions in Example 5 were not within the scope provided in the present disclosure. Comparative Example 5 adopted high-temperature calcination conditions, and the acidic structure of the catalyst was greatly lost. The active components formed partial spinel at high temperature, and the catalyst structure changed, which reduced the catalyst performance. Compared with catalysts AC-4 to AC-5 obtained in Examples 4 to 5, the catalyst AC-1 prepared in Example 1 achieved a higher desulfurization rate.

[0197] The preferred embodiments of the present disclosure are described in detail above. However, the present disclosure is not limited to the specific details of the above embodiments. Within the technical concept of the present disclosure, various simple modifications can be made to the technical solutions of the present disclosure, and these simple modifications all fall within the scope of protection of the present disclosure.

[0198] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the present disclosure will not further describe various possible combinations.

[0199] In addition, the various embodiments of the present disclosure may be arbitrarily combined, and as long as they do not violate the concept of the present disclosure, they should also be regarded as the contents disclosed by the present disclosure.

Claims

1. A modified hydrorefining catalyst, characterized in that: Based on the total weight of the modified hydrorefining catalyst, the modified hydrorefining catalyst comprises 50 to 80 weight percent of a carrier and 18 to 50 weight percent of an active metal component, wherein the active metal component is in the form of a metal oxide; the carrier comprises an acid-modified biochar-coated alumina composite carrier; The active metal component includes a first active metal component and a second active metal component, wherein the first active metal component is selected from one or more metal elements of Group VIII; and the second active metal component is selected from one or more metal elements of Group VIB; The total acid content of the acid-modified biochar-coated alumina composite support measured by pyridine infrared at 150°C is 150-200 μmol / g; the acid-modified biochar-coated alumina composite support contains B acid; the B acid content of the acid-modified biochar-coated alumina composite support measured by pyridine infrared at 150°C is greater than 20 μmol / g; The modified hydrorefining catalyst is a sulfurized modified hydrorefining catalyst, and the sulfurized modified hydrorefining catalyst further includes SO4 2- Species; measured by X-ray photoelectron spectroscopy S spectrum, the sulfurized modified hydrorefining catalyst SO4 2- The content of species is 5~30%; Based on the total weight of the carrier, the carrier includes 0.1 to 15 weight percent of biochar and 85 to 99.9 weight percent of aluminum oxide.

2. The modified hydrotreating catalyst according to claim 1, characterized in that The BET specific surface area of ​​the acid-modified biochar-coated alumina composite carrier is 250-400 m 2 / g.

3. The modified hydrorefining catalyst according to claim 1, characterized in that Based on the total weight of the modified hydrorefining catalyst, the content of the first active metal component is 3 to 10 weight %; the content of the second active metal component is 15 to 40 weight %.

4. The modified hydrorefining catalyst according to claim 1, characterized in that The first active metal component is selected from one or both of Ni and Co; the second active metal component is selected from one or both of Mo and W.

5. A method for preparing an acid-modified biomass carbon-coated alumina composite support for a modified hydrorefining catalyst as claimed in claim 1, characterized in that: The following steps are involved: S1, mixing a biomass raw material, an alumina precursor and an acidic additive to obtain a composite carrier precursor; S2, performing a first calcination treatment on the composite support precursor to obtain a composite support intermediate; S3, subjecting the composite carrier intermediate to hydrothermal treatment.

6. The method according to claim 5, characterized in that In step S1, based on the total weight of the biomass raw material and the alumina precursor, the content of the biomass raw material is 5-40% by weight; the content of the alumina precursor is 60-95% by weight.

7. The method according to claim 6, characterized in that Based on the total weight of the biomass raw material and the alumina precursor, the added amount of the acidic auxiliary agent is 0.1-10% by weight.

8. The method according to claim 5, characterized in that In step S1, the biomass raw material is selected from one or more of corn stalks, wheat stalks, rice stalks and sorghum stalks; The alumina precursor is selected from one or more of pseudo-boehmite, aluminum hydroxide and aluminum nitrate; The acidic auxiliary agent includes a first acidic auxiliary agent and an optional second acidic auxiliary agent; the first acidic auxiliary agent includes sulfuric acid; the second acidic auxiliary agent is selected from one or more of nitric acid, phosphoric acid, citric acid, oxalic acid, tartaric acid, oxalic acid, malic acid, adipic acid and ethylenediaminetetraacetic acid.

9. The method according to claim 8, characterized in that The alumina precursor is pseudo-boehmite.

10. The method according to claim 8, characterized in that The weight ratio of the first acidic auxiliary agent to the second acidic auxiliary agent is 1:0-4.

11. The method according to claim 10, characterized in that The weight ratio of the first acidic auxiliary agent to the second acidic auxiliary agent is 1:0.5-3.

12. The method according to claim 5, characterized in that The method further includes: The biomass raw material is subjected to a first drying treatment, a crushing treatment, and a sieving treatment to obtain a biomass powder with a particle size of less than 60 meshes, which is then mixed with the alumina precursor and the acidic auxiliary agent and ground to a particle size of less than 200 meshes to obtain a composite carrier precursor.

13. The method according to claim 12, characterized in that The conditions of the first drying treatment include: drying at 60-150° C. for 12-36 hours; The conditions of the pulverization treatment include: grinding at 1000-10000 r / min for 12-36 hours.

14. The method according to claim 5, characterized in that In step S2, the conditions of the first calcination treatment include: a calcination temperature of 300-700°C, a calcination time of 3-8 hours; and a calcination atmosphere of one or more of air, nitrogen, oxygen, argon and water vapor.

15. The method according to claim 5, characterized in that Before the first calcination treatment, the composite support precursor is dried at 60-150° C. for 4-15 hours.

16. The method according to claim 5, characterized in that In step S3, the conditions of the hydrothermal treatment include: a hydrothermal temperature of 150-350° C., a hydrothermal time of 2-8 hours; and an atmosphere of the hydrothermal treatment selected from one or more of oxygen, nitrogen, ammonia and carbon dioxide.

17. The method according to claim 5, characterized in that Step S3 also includes: adding deionized water dropwise to the composite carrier intermediate until the composite carrier intermediate reaches a saturated water absorption state, and then performing the hydrothermal treatment.

18. The method according to claim 5, characterized in that The method further includes: cooling the hydrothermal treatment product and then drying it at 60-150° C. for 4-15 hours.

19. A method for preparing the modified hydrotreating catalyst according to claim 1, characterized in that: The following steps are involved: The active metal precursor, the support and the additive are mixed, and then subjected to a forming process and a second calcination process; The carrier includes the acid-modified biochar-coated alumina composite carrier; the active metal precursor includes a first active metal precursor and a second active metal precursor; the first active metal precursor is selected from one or more of the Group VIII metal precursors; and the second active metal precursor is selected from one or more of the Group VIB metal precursors.

20. The method according to claim 19, characterized in that The method comprises: impregnating the solution of the active metal precursor with the carrier.

21. The method according to claim 20, characterized in that The first active metal precursor is selected from one or more of a nickel metal precursor and a cobalt metal precursor; The second active metal precursor is selected from one or more of a molybdenum metal precursor and a tungsten metal precursor.

22. The method according to claim 21, characterized in that The nickel metal precursor is selected from one or more of nickel nitrate, basic nickel carbonate and nickel sulfate; The cobalt metal precursor is selected from one or more of cobalt sulfate, cobalt carbonate, cobalt oxalate and cobalt nitrate; The molybdenum metal precursor is selected from one or more of sodium molybdate, ammonium molybdate, molybdenum chloride and molybdic acid; The tungsten metal precursor is selected from one or more of ammonium metatungstate, phosphotungstic acid and silicotungstic acid.

23. The method according to claim 22, characterized in that The nickel metal precursor is basic nickel carbonate and / or nickel nitrate; The cobalt metal precursor is cobalt nitrate and / or cobalt oxalate; The molybdenum metal precursor is ammonium molybdate; The tungsten metal precursor is ammonium metatungstate and / or phosphotungstic acid.

24. The method according to claim 21, wherein The weight ratio of the first active metal precursor: the second active metal precursor: the acid-modified biochar-coated alumina composite carrier is 0.1-0.7: 0.2-0.9:

1.

25. The method according to claim 19, wherein The conditions of the second calcination treatment include: a calcination temperature of 300-600° C., a calcination time of 3-6 hours, and a calcination atmosphere of one or more of air, nitrogen, oxygen, argon and water vapor.

26. The method according to claim 19, wherein Before the second calcination process, the product obtained by the molding process is dried at 80-160° C. for 4-12 hours.

27. Use of the modified hydrotreating catalyst according to any one of claims 1 to 4 in a crude oil hydrotreating reaction.

28. The use according to claim 27, characterized in that The method comprises the following steps: under hydrogen conditions, the raw oil is brought into contact with the modified hydrofining catalyst to carry out a hydrofining reaction.

29. The use according to claim 28, characterized in that The conditions of the hydrofining reaction include: reaction temperature of 260-380°C; hydrogen pressure of 2-10 MPa; hydrogen-to-oil volume ratio of 200-800:1; raw oil mass space velocity of 0.5-6h -1 .

30. The use according to claim 28, characterized in that The raw oil is selected from gasoline and / or diesel fractions.

31. The use according to claim 28, characterized in that Also includes: The modified hydrotreating catalyst is subjected to a sulfurization treatment before the hydrotreating reaction.

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