CN110508294B

CN110508294B - Preparation method of hydrogenation catalyst, hydrogenation catalyst prepared by method and application of hydrogenation catalyst

Info

Publication number: CN110508294B
Application number: CN201810485163.1A
Authority: CN
Inventors: 韩伟; 龙湘云; 杨清河; 邓中活
Original assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Current assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Priority date: 2018-05-21
Filing date: 2018-05-21
Publication date: 2022-03-11
Anticipated expiration: 2038-05-21
Also published as: CN110508294A

Abstract

The invention relates to the field of hydrorefining, and discloses a preparation method of a hydrogenation catalyst, a catalyst prepared by the method and an application of the catalyst, wherein the preparation method comprises the following steps: (1) introducing tetrathiomolybdate and VIII group metal salt onto a carrier to obtain a composite material A; (2) and (3) carrying out heat treatment on the composite material A under an inert atmosphere or a reducing atmosphere, wherein the heat treatment enables Mo in the composite material A to exist in a trisulfide form and the VIII group metal element to exist in a salt form. The preparation method provided by the invention omits a vulcanization process, the active components of the prepared catalyst are fully vulcanized, and the hydrogenation performance of the catalyst is obviously improved.

Description

Preparation method of hydrogenation catalyst, hydrogenation catalyst prepared by method and application of hydrogenation catalyst

Technical Field

The invention relates to the field of hydrofining, in particular to a preparation method of a hydrogenation catalyst, the hydrogenation catalyst prepared by the method and application of the hydrogenation catalyst in hydrodesulfurization.

Background

The hydrogenation technology is the most important means for producing clean oil products, wherein the high-efficiency hydrogenation catalyst is the core technology of the hydrogenation technology. Uses VIB group metal W or Mo as main active component, VIII group metal Ni or Co as auxiliary active component and gamma-A1₂O₃Or modified gamma-A1₂O₃The supported catalyst as a carrier is a hydrogenation catalyst which is widely used in industry at present. The traditional preparation technology mainly adopts an impregnation method to introduce an oxidized precursor of an active component into a carrier pore passage, and then the hydrogenation catalyst is obtained through aging, drying and roasting. Wherein the Co, Ni, Mo and W active components are present in the form of oxides. However, in actual use, the active components of the hydrogenation catalyst exist in the form of sulfides of Co, Ni, Mo and W, so that the hydrogenation catalyst is subjected to sulfidation activation, namely presulfiding, before use.

Although the traditional preparation technology is applied to large-scale industry due to the advantages of simple operation, low cost and the like, the traditional preparation technology still has a series of problems. On the one hand, when the oxidation type active component is used as the precursor, the oxidation type active component can be used in the dipping and aging processDuring the drying and roasting process, it reacts with Al₂O₃The surface tends to have strong interaction, which not only easily causes uneven dispersion of the active component on the surface of the carrier, but also causes excessive generation of Al-O-Mo chemical bonds, and then causes the active component to be difficult to completely vulcanize, and simultaneously easily forms excessive low-activity I-type active phase, and the utilization rate of the active metal is low (see CN 103143365A). In addition, taking Mo-based catalyst preparation as an example, the commonly used precursor ion Mo₇O₂₄ ^6-Tends to induce Al₂O₃Surface dissociation to produce Al³⁺Subsequently reacted therewith to form the Anderson type heteropolyanion Al (OH)₆Mo₆O₁₈ ^3-The large-grain MoO which is difficult to be fully vulcanized is generated by roasting₃And Al₂(MoO₄)₃Species, which are detrimental to the improvement of catalytic activity (see J.A. Bergwefff et al, Journal of the American Chemical Society 2004,126: 14548; J.A. Bergwefff et al, Catalysis Today 2008,130:117.), and it is therefore difficult to achieve hydrogenation catalysts with both high dispersion of active components and high sulfidity using conventional impregnation techniques, resulting in less than ideal catalytic activity. On the other hand, the prevulcanization process in the traditional preparation technology adopts an in-situ sulfuration technology, namely, firstly, an oxidation state catalyst is loaded into a hydrogenation reactor, and then, hydrogen and a vulcanizing agent are introduced into the reactor for sulfuration in the process of continuously raising the temperature, although the technology is still the most widely applied technology at present, the technology still has a series of problems: 1) the vulcanization time is too long, and the start-up is delayed; 2) the device is easy to corrode and age in the vulcanization process; 3) the vulcanizing agent is inflammable and toxic, and is easy to cause environmental pollution; 4) higher cost, etc. In view of the problems of the "in-plant" vulcanization technology, CN1861258A, CN1861260A, CN101088619A, CN101088620A, CN1994567A, CN101279296A, CN101491725A, US6365542 developed a series of "out-of-plant" vulcanization technologies, which mainly include two routes: the first technical route is to introduce the sulfurizing agent (elemental sulfur, vegetable oil, organic sulfide, organic polysulfide, sulfone and sulfoxide, etc.) into the pores of the hydrogenation catalyst in oxidized state by sublimation, melting or impregnation, and then to carry out the reaction under inert gasSulfurizing the catalyst by heat treatment in the presence of the catalyst; the second technical route is to complete the presulfiding of the catalyst in the oxidation state in the presence of hydrogen and hydrogen sulfide or readily decomposable organic sulfiding agents on a dedicated presulfiding unit. However, no matter the in-situ or ex-situ vulcanization is adopted, the catalyst is required to be firstly oxidized and then presulfurized, so that the preparation process of the catalyst is complex and the economic efficiency is poor.

In order to realize that the hydrodesulfurization catalyst has higher active component dispersion degree, ensure the full vulcanization of the active component, avoid the problems in the in-reactor vulcanization process and simplify the ex-reactor vulcanization route, the direct preparation route of the vulcanization type hydrodesulfurization catalyst in recent years gets more and more attention and exploration.

For example, CN1569331A discloses a modified cobalt molybdenum-based sulfide catalyst and a preparation method thereof, wherein a black powdery catalyst is prepared by preparing an ammonium thiomolybdate solution, coprecipitating molybdenum, cobalt and a third transition metal component, and calcining under the protection of nitrogen.

US6451729 non-supported MoS with high specific surface area is produced by dissolving thiomolybdic acid in organic solvent in the presence of high-temperature hydrogen₂The catalyst has high hydrocracking activity. The disadvantages of such processes are the high cost of catalyst preparation and the only possibility to prepare powdered catalysts, which cannot be used in large scale hydrogenation plants.

CN1557917A discloses a sulfide type hydrogenation catalyst and a preparation method thereof, wherein the preparation method of the catalyst mainly comprises the steps of introducing precursors of VIB group metals Mo and W into gaps of a hydrogenation catalyst carrier by adopting soluble thiomolybdate and thiotungstate solutions to the carrier of a conventional catalyst, roasting for 4 hours at 350 ℃ under the protection of nitrogen, dipping by using a solution containing Ni and Co, and roasting for 4 hours at 350 ℃ under the protection of nitrogen, thereby preparing the supported sulfide catalyst of Mo, W, Co and Ni. In the process of preparing the thiomolybdate and the thiotungstate solution, an organic solvent is added, and in the high-temperature treatment process, due to volatilization of the organic solvent, the interaction between an active metal component and a carrier is enhanced, the vulcanization of the active metal is influenced, the metal vulcanization degree is lower, and the activity and the selectivity of the catalyst are influenced.

CN102039147A discloses a preparation method of a sulfuration type catalyst, which adopts alkyl molybdenum (tungsten) sulfide ammonium salt containing metal Mo or W, inorganic salt of Ni or Co and organic auxiliary agent as impregnation liquid, impregnates a required catalyst carrier, and directly obtains the sulfuration type catalyst by drying. The method has the advantages of simple preparation process, no need of inert gas protection in the preparation process, easy formation of II-type active phase with high catalytic activity, and high catalyst service performance, but finally has high preparation cost and low application possibility because the thio-molybdenum (tungstate) which is difficult to synthesize and has very high price is also adopted as an active precursor.

CN104707629A discloses a preparation method of a supported transition metal sulfide hydrogenation catalyst, which adopts tetrathiomolybdate and soluble nickel and cobalt salts to prepare a Ni (Co) MoS hydrofining catalyst with high sulfidity by a three-step method of liquid-phase impregnation adsorption-precipitation-high-temperature reduction. Compared with the method, the method avoids the use of a template agent, an alkaline solution and an organic solvent. However, in the preparation method, under the condition of a certain solution volume, the loading amount of the active metal is uncontrollable in the liquid-phase impregnation and adsorption process, and the relative atomic ratio of the auxiliary active component Ni (Co) to the main active component Mo is difficult to adjust; in addition, in the adsorption equilibrium and precipitation, active metal components which cannot be loaded on the carrier still exist in the solution, so that the metal utilization rate is low, and the raw material loss is caused.

In conclusion, the activity of the sulfided hydrogenation catalyst provided by the prior art is improved to some extent, but the improvement degree is limited, and the preparation method of the sulfided hydrogenation catalyst has the defects of more complex preparation route, poorer controllability and higher cost, so that the industrial application of the methods is limited to a certain extent.

Disclosure of Invention

Aiming at the defects of lower activity, more complex preparation process, poorer controllability and higher cost of the hydrogenation catalyst in the prior art, the invention provides a novel preparation method of the hydrogenation catalyst, the hydrogenation catalyst prepared by the method and the application of the hydrogenation catalyst in hydrodesulfurization.

The invention provides a preparation method of a hydrogenation catalyst, which comprises the following steps: (1) introducing tetrathiomolybdate and VIII group metal salt onto a carrier to obtain a composite material A; (2) and (3) carrying out heat treatment on the composite material A under an inert atmosphere or a reducing atmosphere, wherein the heat treatment enables Mo in the composite material A to exist in a trisulfide form and the VIII group metal element to exist in a salt form.

The invention provides a hydrogenation catalyst prepared by the preparation method.

The invention also provides the application of the hydrogenation catalyst in hydrodesulfurization.

The inventor of the invention discovers through research that in the process of preparing a hydrogenation catalyst, tetrathiomolybdate and VIII group metal salt are firstly introduced onto a carrier to obtain a composite material A; and then carrying out heat treatment on the composite material A in an inert atmosphere or a reducing atmosphere, wherein the heat treatment enables Mo in the composite material A to exist in a trisulfide form and VIII group metal elements to exist in a salt form, so that the hydrogenation catalyst with better hydrogenation performance can be obtained.

The hydrogenation catalyst provided by the invention can be activated only by simply carrying out heat treatment on the catalyst in the process of startup without a vulcanization process, so that the startup period is greatly saved, the startup cost is saved, and the safety risk of a refinery is reduced.

In a preferred aspect, the method for introducing tetrathiomolybdate and the group VIII metal salt onto the support in step (1) is: preparing a tetrathiomolybdate solution, adding a group VIII metal salt to the tetrathiomolybdate solution to form a mixed solution, impregnating the carrier with the mixed solution, and then drying the impregnated carrier; or impregnating the support with a tetrathiomolybdate solution and a group VIII metal salt-containing solution, respectively, and drying after each impregnation.

Further preferably, the tetrathiomolybdate solution is prepared by the following method: a) mixing a molybdenum-containing compound, an organic sulfur source, and water; b) reacting the mixture obtained in step a) for 2-24h at 50-100 ℃ and/or pH 5-10; the organic sulfur source is a sulfur-containing material capable of being hydrolyzed under the conditions of step a) and/or step b). The method can improve the activity of the catalyst, and directly prepare the hydrogenation catalyst by taking the tetrathiomolybdate solution as an impregnation solution without crystallizing the tetrathiomolybdate, thereby simplifying the operation steps and overcoming the defects of high price and low application possibility of the thiomolybdate in the prior art.

Compared with the prior art, the hydrogenation catalyst provided by the invention has the following advantages:

(1) in the hydrogenation catalyst provided by the invention, Mo is in a vulcanized state, so that a series of problems caused by strong interaction between metal and a carrier can be effectively avoided, the auxiliary agent Co (Ni) can be successfully prevented from being vulcanized before the auxiliary agent Co (Ni), the utilization rate of active metal is improved, and a high-activity II-type Co (Ni) -Mo-S active phase is obtained;

(2) mo in the hydrogenation catalyst provided by the invention exists in a trisulfide state, and the auxiliary component can be vulcanized (MoS) only by simply reducing the catalyst before start-up₃Conversion to MoS₂VIII metal salt is converted into VIII metal sulfide), and II Co (Ni) -Mo-S active phase with higher catalytic performance is obtained, and the catalyst does not need to be presulfurized, so that the start-up time is saved, and the environment is protected;

(3) the method adopts tetrathiomolybdate solution to directly impregnate the carrier, and can effectively improve the utilization rate of metal.

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

FIG. 1 is a diagram showing an ultraviolet-visible absorption spectrum (UV-Vis) of a tetrathiomolybdate solution obtained in example 1; FIG. 2 is an XRD diffraction pattern of hydrogenation catalyst S-1 obtained in example 1.

Detailed Description

The endpoints of the ranges and any values disclosed herein are not limited to the precise range or value, and such ranges or values should be understood to encompass values close to those ranges or values. For ranges of values, between the endpoints of each of the ranges and the individual points, and between the individual points may be combined with each other to give one or more new ranges of values, and these ranges of values should be considered as specifically disclosed herein.

In the present invention, preferably, the method for introducing tetrathiomolybdate and the group VIII metal salt on the support in the step (1) is: preparing a tetrathiomolybdate solution, adding a group VIII metal salt to the tetrathiomolybdate solution to form a mixed solution, impregnating the carrier with the mixed solution, and then drying the impregnated carrier; or impregnating the support with a tetrathiomolybdate solution and a group VIII metal salt-containing solution, respectively, and drying after each impregnation.

In order to further improve the hydrogenation performance of the catalyst obtained, simplify the operation steps, and reduce the catalyst production cost, it is preferable that the tetrathiomolybdate solution is prepared by the following method:

a) mixing a molybdenum-containing compound, an organic sulfur source, and water;

b) reacting the mixture obtained in step a) for 2-24h at 50-100 ℃ and/or pH 5-10;

the organic sulfur source is a sulfur-containing material capable of being hydrolyzed under the conditions of step a) and/or step b).

According to the present invention, the concentration of the tetrathiomolybdate solution can be selected in a wide range, and those skilled in the art can select the concentration according to actual conditions. For example, to load a specific amount of molybdenum, the concentration of the tetrathiomolybdate solution can be calculated from the water absorption of the carrier. The tetrathiomolybdate solution prepared as described above may be concentrated or diluted in order to obtain an appropriate concentration of the tetrathiomolybdate solution. The tetrathiomolybdate solution preferably has a concentration of 0.2 to 1.8mol/L, and more preferably 0.3 to 1.2 mol/L.

By the method, tetrathiomolybdate is directly utilized, active metal components can be effectively utilized, and waste of active metal is avoided.

The tetrathiomolybdate solution provided by the invention only contains a small amount of volatile impurity ions, such as CH₃COO^-、NH₄ ⁺And the tetrathiomolybdate solution can be naturally removed in the subsequent catalyst preparation process, the heat treatment process or the drying process, so that the tetrathiomolybdate solution obtained by the method provided by the invention can be directly used as an impregnation solution, the tetrathiomolybdate solution is obtained without crystallization and purification and then dissolved to be used as the impregnation solution, and the operation steps are simplified.

In the prior art, hydrogen sulfide is mostly adopted as a sulfur source in the process of preparing a tetrathiomolybdate solution, and in order to fully dissolve the molybdenum source in water, a cosolvent such as ammonia water is mostly added, so that the ammonia water with pungent odor is required to be used in the whole tetrathiomolybdate solution process, and the problem that highly toxic and malodorous hydrogen sulfide gas needs to be treated cannot be solved. In the process of preparing the tetrathiomolybdate solution, the molybdenum-containing compound, the organic sulfur source and water are mixed; and then the pH of the mixture is adjusted by heating the mixture and/or adding acid and alkali so that the organic sulfur source is completely dissolved in water, and during the reaction, the O-S exchange reaction is fully performed between the molybdenum-containing compound and the organic sulfur source.

The present invention provides a wide range of options for the manner in which the molybdenum-containing compound, the organic sulfur source and water are mixed, preferably the mixing in step a) comprises: the molybdenum-containing compound is dissolved in water to form a first solution, and then a source of organic sulfur is added to the first solution. With this preferred embodiment, it is more advantageous to mix the molybdenum-containing compound and the organic sulfur source uniformly. Preferably, the preparation of the first solution and the addition of the organic sulfur source are carried out under stirring conditions to allow for more complete and uniform contact between the tetrathiomolybdate and the organic sulfur source. The stirring speed may be 10-500 rpm.

In the present invention, the concentration of the first solution is not particularly limited, but the concentration of the molybdenum-containing compound in the first solution is preferably 0.2 to 0.5mol/L, more preferably 0.3 to 0.4mol/L, in terms of Mo element.

In the present invention, the molybdenum-containing compound is preferably at least one selected from the group consisting of sodium molybdate, ammonium paramolybdate, ammonium phosphomolybdate and molybdenum trioxide, and more preferably sodium molybdate and/or ammonium paramolybdate. When the molybdenum-containing compound is molybdenum trioxide, the invention also comprises introducing ammonia water or an inorganic acid into the first solution for dissolution assistance, and the introduction amount thereof is not particularly limited.

The amount of the organic sulfur source and the molybdenum-containing compound used in the present invention is selected from a wide range as long as the molar ratio of the organic sulfur source in terms of sulfur element to the molybdenum-containing compound in terms of molybdenum element is not less than 4, preferably 4 to 6:1, more preferably 4 to 5.5: 1. The adoption of the preferred embodiment can not only meet the reaction requirements of the two, but also effectively utilize the raw materials and avoid resource waste.

The mixture obtained in the step a) is reacted for 2 to 24 hours under the conditions of 50 to 100 ℃ and/or pH value of 5 to 10, namely, the O-S exchange can be fully carried out, and in order to ensure that the O-S exchange is more fully carried out, the mixture obtained in the step a) is preferably reacted for 2 to 24 hours, preferably 10 to 16 hours, at 70 to 100 ℃, or is reacted for 2 to 24 hours, preferably 3 to 7 hours under the condition of pH value of 5 to 6, or is reacted for 2 to 24 hours, preferably 3 to 7 hours under the condition of pH value of 8 to 10. At the above reaction temperature, if the reaction time is too short, the hydrolysis of the organic sulfur source is not sufficiently performed, and the O-S exchange is not sufficiently performed, and the sulfur source utilization rate is lowered.

According to a preferred embodiment of the invention, the reaction is carried out under closed conditions. The operation is carried out under a closed condition, the hydrogen sulfide obtained by hydrolyzing the organic sulfur source can not be released into the air, the air pollution can not be caused, the hydrolysis of the hydrogen sulfide into divalent sulfur ions can be facilitated, the sulfur source can be more effectively utilized, and the tetrathiomolybdate solution with better performance can be more effectively prepared.

According to the present invention, it is preferable that the pH is adjusted in step b) by adding an acid and/or a base to the mixture, and the acid may be an organic acid or an inorganic acid, which is not particularly limited in the present invention.

According to the present invention, preferably, the acid is at least one selected from the group consisting of hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, formic acid, and acetic acid, and further preferably hydrochloric acid. By adopting the preferred embodiment, the introduced impurity elements are naturally removed in the heat treatment or drying process in the later stage of the catalyst preparation, and the performance of the catalyst is not influenced.

According to the present invention, preferably, the base is at least one selected from the group consisting of ammonia water, sodium hydroxide, and potassium hydroxide, and more preferably sodium hydroxide.

According to a preferred embodiment of the present invention, the tetrathiomolybdate solution is prepared by the following method:

the organic sulfur source may be any of a variety of sulfur-containing species capable of being hydrolyzed under the conditions of step (1) and/or step (2). Preferably, the organic sulfur source is at least one selected from the group consisting of L-cysteine, a thioamide represented by formula (1), a monothioester represented by formula (2), and a dithioester represented by formula (3),

in the formula (1), R¹Is NH₂-、CH₃-、CH₃CH₂-、CH₃NH-or (CH)₃)₂N-，R²And R³Each independently is H or C1-C4 alkyl; in the formula (2), R⁴Is H or C1-C4 alkyl, R⁵Is C1-C4 alkyl; in the formula (3), R⁶Is H or C1-C4 alkyl, R⁷Is a C1-C4 alkyl group, said C1-C4 alkyl group may be methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl or tert-butyl. R²And R³May be the same or different.

According to the invention, the organic sulfur source may be any of a variety of sulfur-containing species capable of being hydrolyzed under the conditions of step (1) and/or step (2). Preferably, the organic sulfur source is at least one selected from the group consisting of L-cysteine, a thioamide represented by formula (1), a monothioester represented by formula (2), and a dithioester represented by formula (3),

in the formula (1), R¹Is NH₂-、CH₃-、CH₃CH₂-、CH₃NH-or (CH)₃)₂N-，R²And R³Each independently is H or C1-C4 alkyl; in the formula (2), R⁴Is H or C1-C4 alkyl, R⁵Is C1-C4 alkyl; in the formula (3), R⁶Is H or C1-C4 alkyl, R⁷Is a C1-C4 alkyl group, said C1-C4 alkyl group may be methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl or tert-butyl. R²And R³May be the same or different. More preferably, the organic sulfur source is a thioamide represented by formula (1), still more preferably, the organic sulfur source is thiourea and/or thioacetamide, and most preferably, thioacetamide.

According to a preferred embodiment of the present invention, there is provided a method for preparing a hydrogenation catalyst comprising: a) mixing a molybdenum-containing compound, an organic sulfur source, and water; b) reacting the mixture obtained in step a) for 2-24h at 50-100 ℃ and/or pH 5-10; c) adding VIII group metal salt into the tetrathiomolybdate solution obtained in the step b) to form a mixed solution, soaking the carrier by using the mixed solution, and then drying to obtain a composite material A; or respectively adopting the tetrathiomolybdate solution obtained in the step b) and the solution containing the VIII group metal salt to impregnate the carrier, and drying after each impregnation to obtain a composite material A; d) carrying out heat treatment on the obtained composite material A in an inert atmosphere or a reducing atmosphere, wherein Mo in the composite material A exists in a trisulfide form through the heat treatment; wherein the organic sulfur source is a sulfur-containing material that is capable of being hydrolyzed under the conditions of step a) and/or step b).

According to the present invention, before the step c), the tetrathiomolybdate solution obtained in the step b) may be concentrated or diluted to 0.2-1.8mol/L, and further preferably concentrated or diluted to 0.3-1.2 mol/L.

In the present invention, the concentration of the group VIII metal salt solution in the mixed solution or the group VIII metal salt-containing solution is not particularly limited, but the concentration of the group VIII metal salt solution is preferably 0.1 to 1mol/L, and more preferably 0.3 to 1 mol/L.

In order to further improve the hydrogenation performance of the hydrogenation catalyst, the tetrathiomolybdate, the VIII group metal salt and the carrier are preferably used in such amounts that the carrier is present in an amount of 59 to 90 wt%, the VIII group metal element is present in an amount of 1 to 15 wt% and the Mo is present in an amount of 5 to 40 wt%, based on the total amount of the catalyst, in terms of oxides. More preferably, the tetrathiomolybdate, the group VIII metal salt and the support are used in amounts such that the support is present in an amount of 65 to 85 wt.%, more preferably 71 to 84 wt.%, based on the total amount of the catalyst; the content of the group VIII metal element is 1 to 10% by weight, more preferably 1.5 to 6% by weight, in terms of oxide; the content of Mo is 8 to 30% by weight, more preferably 10 to 23% by weight.

In the present invention, preferably, the group VIII metal salt is selected from one or more of nitrate, carbonate, chloride, sulfate and acetate salts of cobalt and/or nickel.

In the present invention, it is preferable that the group VIII metal salt is added in a molar ratio of the tetrathiomolybdate to the metal element of 0.1 to 1, preferably 0.2 to 0.5. Such a preferred embodiment is more beneficial for the synergistic effect of the group VIII metal and Mo, and for the formation of the active phase, and also for the complete sulfidation of Mo when the catalyst is subjected to a reduction treatment prior to start-up.

According to the present invention, in the step (1), the solid material after impregnation is dried each time during the introduction of the solution of tetrathiomolybdate and the group VIII metal salt to the support by impregnation, and the drying conditions are not particularly limited in the present invention, and may be various drying conditions commonly used in the art, for example, the drying conditions include: the temperature is 80-120 ℃, and the time is 2-8 h; preferably, the temperature is 80-100 ℃ and the time is 3-6 h. The drying may be carried out under air, but in order to ensure that the sulphide is not lost, it is preferred that the drying is carried out under an inert atmosphere.

According to the present invention, in the step (2), the inert atmosphere may be provided by one or more of nitrogen, argon and helium, preferably nitrogen.

According to the invention, the reducing atmosphere may be provided by hydrogen and/or hydrogen sulphide and optionally an inert gas. The reducing atmosphere may contain an inert gas, and when the inert gas is contained in the reducing atmosphere, the volume content of hydrogen and/or hydrogen sulfide is not less than 5%.

In the present invention, the heat treatment conditions for the composite material a in step (2) must be such that Mo in the composite material a exists in the form of trisulfide, preferably, under an inert atmosphere, and the heat treatment conditions include: the temperature is 250 ℃ and 300 ℃, and the time is 2-8 h; preferably, the temperature is 260-270 ℃, and the time is 3-6 h; preferably, the heat treatment conditions include, under a reducing atmosphere: the temperature is 200 ℃ and 250 ℃, and the time is 2-8 h; preferably, the temperature is 200 ℃ and 230 ℃, and the time is 3-6 h.

The heat treatment temperature is neither too high nor too low, when the heat treatment temperature is too high, the active metal component Mo in the composite material A is easy to exist in a disulfide form directly, the subsequent vulcanization of the auxiliary active component is not facilitated, the formation of a II-type active phase is also not facilitated, and when the heat treatment temperature is too low, the decomposition of tetrathiomolybdate is not facilitated.

The selection of the carrier is not particularly limited, and the carrier may be selected from one or more of γ -alumina, silica, alumina-silica, titania, magnesia, silica-zirconia, silica-thoria, silica-beryllia, silica-titania, silica-zirconia, titania-zirconia, silica-alumina-thoria, silica-alumina-titania, silica-alumina-magnesia and silica-alumina-zirconia, for example, and will not be described herein again.

The impregnation method is not particularly limited in the present invention, and various impregnation methods conventionally used in the art, such as equal volume impregnation, may be used, and will not be described herein again.

The hydrogenation catalyst prepared by the preparation method has excellent hydrodesulfurization activity, so the invention also provides the hydrogenation catalyst prepared by the preparation method and the application thereof in hydrodesulfurization.

The invention also provides a hydrogenation catalyst, and the catalyst is prepared by any one of the methods provided by the invention. The catalyst comprises a carrier and an active metal component loaded on the carrier, wherein the active metal component comprises Mo and at least one VIII group metal element, the Mo exists in a form of trisulfide, and the VIII group metal element exists in a form of salt.

In the hydrogenation catalyst provided by the invention, Mo exists in a form of trisulfide, the VIII group metal element exists in a form of salt, and the auxiliary agent component can be vulcanized (MoS) only by simply reducing the catalyst before start-up₃Conversion to MoS₂The VIII group metal salt is converted into the VIII group metal sulfide), and II-type Co (Ni) -Mo-S active phase with higher catalytic performance is obtained, and the hydrogenation performance is better.

In the present invention, the presence form of Mo in the hydrogenation catalyst can be measured by an X-ray diffraction method. MoS₃There is a diffuse peak on the XRD pattern at 14.2 ° 2 θ. In the hydrogenation catalyst provided by the invention, the VIII group metal element basically exists in the form of VIII group metal active precursor, namely the VIII group metal element exists in the form of salt, and the VIII group metal element can be salt with crystal water or salt without crystal water.

The catalyst provided by the invention has high degree of sulfuration, and preferably, the degree of sulfuration of the catalyst is 96.5-99% as measured by an X-ray electron energy spectrum.

In the present invention, unless otherwise specified, the degree of sulfidation of the catalyst is determined by X-ray photoelectron spectroscopy (XPS), wherein the degree of sulfidation is obtained by processing XPS data, as described in Han et al, Journal of Materails Chemistry 2012,22: 25340.

The selection range of the content of each component in the catalyst is wide, and preferably, the content of the carrier is 59-90 wt% based on the total amount of the catalyst, the content of the VIII group metal element is 1-15 wt% calculated by oxide, and the content of Mo is 5-40 wt%.

According to a preferred embodiment of the present invention, the carrier is present in an amount of 65 to 85 wt.%, more preferably 71 to 84 wt.%, based on the total amount of catalyst; the content of the group VIII metal element is 1 to 10% by weight, more preferably 1.5 to 6% by weight, in terms of oxide; the content of Mo is 8 to 30% by weight, more preferably 10 to 23% by weight.

The catalyst component contents were measured by X-ray fluorescence spectroscopy RIPP 132-90 (petrochemical analysis (RIPP test), Yangchini, Kangying, Wu Wenhui ed., first 9 months 1990, 371) 379.

It should be noted that the active metal components are present in the form of sulfide and salt, respectively, and the metal components are calculated as oxide contents. Obviously, when the catalyst contains only the above components, the content of each component must satisfy 100%.

In the present invention, it is preferable that the group VIII metal element is a cobalt and/or nickel element.

The carrier of the catalyst of the present invention is not particularly limited, and may be a porous oxide carrier, and may be selected from, for example, γ -alumina, silica, alumina-silica, titania, magnesia, silica-zirconia, silica-thoria, silica-beryllia, silica-titania, silica-zirconia, titania-zirconia, silica-alumina-thoria, oxygen, and the likeOne or more of silica-alumina-titania, silica-alumina-magnesia, and silica-alumina-zirconia. Particularly preferably, the carrier is gamma-Al with the diameter of 2mm to 5mm₂O₃And (3) granules. The above-mentioned carrier can be obtained commercially, or can be prepared by a conventional method.

The catalyst provided by the invention does not need to be presulfurized before use, and only needs to be subjected to simple reduction treatment during start-up to sulfide the auxiliary agent component (MoS)₃Conversion to MoS₂Group VIII metal salts to group VIII metal sulfides) and to obtain a group II co (ni) -Mo-S active phase with higher catalytic performance.

Accordingly, the present invention also provides a process for hydrofinishing, which process comprises: the hydrogenation catalyst provided by the invention is activated to obtain an activated catalyst, and a raw material to be hydrorefined is contacted with the activated catalyst in the presence of hydrogen under the hydrorefining condition.

According to the hydrofining method provided by the present invention, preferably, the activating conditions include: under the inert atmosphere or the reducing atmosphere, the temperature is 240-500 ℃, and the time is 1-12 h; further preferably, the activation is carried out for 0.5-6h at a temperature of 240-310 ℃ and then for 0.5-6h at a temperature of 320-500 ℃ in an inert atmosphere or a reducing atmosphere. The inventor finds that the activation process is firstly carried out at low temperature (240-.

According to a preferred embodiment of the invention, the activated catalyst has a degree of sulfidation of 90 to 100% (preferably 95 to 99%) and a degree of co-agent modification of 30 to 70% (preferably 40 to 60%). In the present invention, unless otherwise specified, the degree of sulfidation of the catalyst is determined by X-ray photoelectron spectroscopy (XPS), wherein the degree of sulfidation is obtained by processing XPS data, as described in Han et al, Journal of Materails Chemistry 2012,22: 25340.

The modification degree of the auxiliary agent refers to hydrogenation catalysis in the catalystThe content of II active phases A-B-S of the oxidant, wherein A represents VIII metal elements (such as Co and Ni), B represents Mo element, and S is sulfur element. In the hydrogenated catalyst after being vulcanized, VIII group metal elements exist in different forms, for example, Co is taken as an example, in the vulcanized CoMo catalyst, Co is respectively Co²⁺Co-Mo-S and Co₉S₈The Co existing in different forms corresponds to peaks at different positions in the XPS spectrogram, and the Co is calculated by unfolding the peaks²⁺Co-Mo-S and Co₉S₈Corresponding peak area by Co-Mo-S corresponding peak area/(Co)²⁺Corresponding peak area + Co-Mo-S corresponding peak area + Co₉S₈Corresponding peak area) x 100% to calculate the content of II active phase Co-Mo-S, and the method is also suitable for NiMo catalyst. The specific calculation method can be found in Qielimei article (X-ray photoelectron spectroscopy is used to study the chemical state of active elements in hydrodesulfurization catalyst [ J]And petroleum science and newspaper: petroleum processing, 2011, 27 (4): 638-642).

The catalyst provided by the invention can be used for any raw material needing hydrofining, is particularly suitable for the hydrofining process or the hydrogenation pretreatment process of petroleum distillate oil or coal liquefaction distillate oil, and preferably, the raw material to be hydrofined is the petroleum distillate oil or the coal liquefaction distillate oil. The present invention is illustrated in the examples by using gasoline and diesel fuel model compounds, but the present invention is not limited thereto.

According to the hydrofinishing process of the present invention, the hydrofinishing conditions may be conventional hydrofinishing conditions. For example: the temperature can be 200-425 ℃, preferably 300-400 ℃; the hydrogen partial pressure may be from 1 to 15 MPa, preferably from 2 to 8 MPa; the volume ratio of the hydrogen to the oil can be 100-5000, and preferably 200-1000; the liquid hourly space velocity can be 0.2-5 hours^-1Preferably 0.2 to 3 hours^-1。

The following detailed description is provided for the purpose of illustrating the embodiments and the advantageous effects thereof, and is intended to help the reader to clearly understand the spirit of the present invention, but not to limit the scope of the present invention.

In the following examples, the contents of the components in the catalyst were measured by X-ray fluorescence spectroscopy (XRF) using a ZSX-100e X-ray fluorescence spectrometer at a current of 50mA and a voltage of 50kV using an Rh target.

The degree of sulfidation of Mo as the main agent in the catalyst was determined by X-ray photoelectron spectroscopy (XPS) which was obtained by processing XPS data and was carried out in the ESCA Lab 250X-ray photoelectron spectroscopy (VG, uk) using Al K α as a radiation source, 0.5eV as a resolution, and 285.0eV as a binding energy of C1s contaminated with carbon as an internal standard.

The existence form of Mo in the catalyst is characterized by XRD (X-ray diffraction), and an XRD spectrogram is collected by a Rigaku D/Max 3400 type X-ray diffractometer; the diffraction pattern was scanned over a range of 5-70 deg. (2 theta), using a Cu Ka radiation source and a scan speed of 38 deg./min.

Example 1

(1) Preparation of mixed solution of tetrathiomolybdate and nickel acetate

(a) Mixing sodium molybdate with water, stirring for 40min, adding thioacetamide, stirring for 30min to obtain 40mL of solution containing 0.35mol/L of sodium molybdate and 1.75mol/L of thioacetamide, heating to 95 ℃ under a closed condition, and reacting for 10h to obtain tetrathiomolybdate solution; the obtained tetrathiomolybdate solution was subjected to UV-Vis test, and the UV-Vis characterization results are shown in FIG. 1, in which peaks at wavelengths of 260nm, 317nm and 468nm indicate MoS in the solution₄ ^2-Presence of (a); (b) according to the weight ratio of Ni: nickel acetate was weighed at a Mo molar ratio of 0.5, added to the above solution to obtain a mixed solution, which was then concentrated to 8 mL.

(2) Preparation of hydrogenation catalyst

The mixed solution is adopted to treat 10g of gamma-Al with the diameter of 2-5mm₂O₃Support (specific surface area 231 m)²Per g, pore volume 0.709mL/g, the same applies below) for 4h, followed by drying at 80 ℃ for 3h under nitrogen atmosphere to obtain composite material A; then compounding at 270 ℃ in a nitrogen atmosphereAnd carrying out heat treatment on the material A for 4h to obtain the hydrogenation catalyst S-1. XRD characterization of S-1, as shown in FIG. 2, it can be seen from FIG. 2 that MoS appears at 14.2 ° 2 θ₃Characteristic dispersion peak of (1), proving that molybdenum in S-1 is MoS₃The nickel salt is not decomposed under the heat treatment condition, and the nickel element in the hydrogenation catalyst S-1 exists in the form of salt. The results of the analysis of the contents of the components in the catalyst are shown in Table 1.

Example 2

(1) Preparation of mixed solution of tetrathiomolybdate and nickel nitrate

(a) Mixing ammonium paramolybdate with water, stirring for 40min, adding thioacetamide, stirring for 30min to prepare 30mL of a solution containing 0.045mol/L of ammonium paramolybdate and 1.26mol/L of thioacetamide, heating the solution to 80 ℃ under a sealed condition to react for 16h to obtain a tetrathiomolybdate solution, and then concentrating the tetrathiomolybdate solution to 8 mL; the obtained tetrathiomolybdate solution is subjected to UV-Vis test, the characterization result of the UV-Vis is consistent with that of figure 1, peaks are formed at the positions with the wavelengths of 260nm, 317nm and 468nm in the figure, and MoS in the solution is shown₄ ^2-Presence of (a); (b) nickel nitrate was weighed in a molar ratio of Ni to Mo of 0.3, and added to the above solution to obtain a mixed solution, which was then concentrated to 8 mL.

(2) Preparation of hydrogenation catalyst

The mixed solution is adopted to treat 10g of gamma-Al with the diameter of 2-5mm₂O₃Carrying out saturated impregnation on the carrier for 4h, and then drying the carrier for 3h at 80 ℃ in an argon atmosphere to obtain a composite material A; then, carrying out heat treatment on the composite material A for 6 hours at 260 ℃ in a nitrogen atmosphere to obtain a hydrogenation catalyst S-2; XRD characterization and analysis are carried out on S-2, and MoS appears at the position of 14.2 degrees of 2 theta₃Characteristic dispersion peak of (1), proving MoS of molybdenum in S-2₃The form exists; under the condition of heat treatment, the nickel salt is not decomposed, and the nickel element in the hydrogenation catalyst S-2 exists in the form of salt. The results of the analysis of the contents of the components in the catalyst are shown in Table 1.

Example 3

(1) Preparation of mixed solution of tetrathiomolybdate and nickel acetate

(a) Mixing sodium molybdate with water, stirring for 40min, addingAdding thioacetamide, stirring for 30min to prepare 30mL of solution containing 0.35mol/L sodium molybdate and 1.75mol/L thioacetamide, heating the solution to 70 ℃ under a closed condition for reaction for 14h to obtain tetrathiomolybdate solution, and then concentrating the tetrathiomolybdate solution to 4 mL; the obtained tetrathiomolybdate solution is subjected to UV-Vis test, the characterization result of the UV-Vis is consistent with that of figure 1, peaks are formed at the positions with the wavelengths of 260nm, 317nm and 468nm in the figure, and MoS in the solution is shown₄ ^2-Presence of (a); (b) nickel acetate was weighed in a molar ratio of Ni to Mo of 0.4, and added to the above solution to obtain a mixed solution, which was then concentrated to 4 mL.

(2) Preparation of hydrogenation catalyst

The mixed solution is adopted to treat 10g of gamma-Al with the diameter of 2-5mm₂O₃Carrying out saturated impregnation on the carrier for 4h, and then drying the carrier for 3h at 80 ℃ in a nitrogen atmosphere to obtain a composite material A; then, carrying out heat treatment on the composite material A for 3h at 200 ℃ in a hydrogen atmosphere to obtain a hydrogenation catalyst S-3; XRD characterization and analysis are carried out on the hydrogenation catalyst S-3, and MoS appears at the position of 14.2 degrees of 2 theta₃The characteristic dispersion peak of the catalyst proves that the molybdenum in the hydrogenation catalyst S-3 is MoS₃The form exists; under the condition of heat treatment, the nickel salt is not decomposed, and the nickel element in the hydrogenation catalyst S-3 exists in the form of salt. The results of the analysis of the contents of the components in the catalyst are shown in Table 1.

Example 4

(1) Preparation of mixed solution of tetrathiomolybdate and cobalt acetate

(a) Mixing sodium molybdate with water, stirring for 40min, adding thioacetamide, stirring at 40 ℃ for dissolving, preparing 30mL of a solution containing 0.4mol/L of sodium molybdate and 2mol/L of thioacetyl, dropwise adding 2.4M hydrochloric acid under the stirring condition to adjust the pH value to 5-6, and reacting for 6h under the closed condition to obtain a tetrathiomolybdate solution; the obtained tetrathiomolybdate solution is subjected to UV-Vis test, the characterization result of the UV-Vis is consistent with that of figure 1, peaks are formed at the positions with the wavelengths of 260nm, 317nm and 468nm in the figure, and MoS in the solution is shown₄ ^2-Presence of (a); (b) cobalt acetate was weighed in a molar ratio of Co to Mo of 0.5, and added to the above solution to obtain a mixed solution, which was then concentrated to 8 mL.

(2) Preparation of hydrogenation catalyst

The mixed solution is adopted to treat 10g of gamma-Al with the diameter of 2-5mm₂O₃Carrying out saturated impregnation on the carrier for 4h, and then drying the carrier for 3h at 80 ℃ in a nitrogen atmosphere to obtain a composite material A; then, carrying out heat treatment on the composite material A for 4 hours at 270 ℃ in a nitrogen atmosphere to obtain a hydrogenation catalyst S-4; XRD characterization and analysis are carried out on the hydrogenation catalyst S-4, and MoS appears at the position of 14.2 degrees 2 theta₃Characteristic dispersion peak of (1), proving that molybdenum in S-4 is MoS₃The form exists; under the condition of heat treatment, the cobalt salt is not decomposed, and the cobalt element in the hydrogenation catalyst S-4 exists in the form of salt. The results of the analysis of the contents of the components in the catalyst are shown in Table 1.

Example 5

(1) Preparation of mixed solution of tetrathiomolybdate and cobalt acetate

(a) Mixing sodium molybdate with water, stirring for 40min, adding thiourea, stirring and dissolving at 40 ℃, preparing to obtain 30mL of a solution containing 0.35mol/L of sodium molybdate and 2mol/L of thiourea, heating to 70 ℃ for reaction for 4 hours under a closed condition, and heating to 97 ℃ for reaction for 6 hours to obtain a tetrathiomolybdate solution; the obtained tetrathiomolybdate solution is subjected to UV-Vis test, the characterization result of the UV-Vis is consistent with that of figure 1, peaks are formed at the positions with the wavelengths of 260nm, 317nm and 468nm in the figure, and MoS in the solution is shown₄ ^2-Presence of (a); (b) according to the weight ratio of Co: weighing cobalt acetate with the Mo molar ratio of 0.5, adding the cobalt acetate into the solution to obtain a mixed solution, and then concentrating the mixed solution to 4 mL;

(2) preparation of hydrogenation catalyst

The mixed solution is adopted to treat 10g of gamma-Al with the diameter of 2-5mm₂O₃Carrying out saturated impregnation on the carrier for 4h, and then drying the carrier for 3h at 80 ℃ in an argon atmosphere to obtain a composite material A; then, carrying out heat treatment on the composite material A for 4 hours at 270 ℃ in a nitrogen atmosphere to obtain a hydrogenation catalyst S-5; XRD characterization and analysis are carried out on the hydrogenation catalyst S-5, and MoS appears at the position of 14.2 degrees of 2 theta₃Characteristic dispersion peak of (1), proving MoS of molybdenum in S-5₃The form exists; under the condition of heat treatment, the cobalt salt is not decomposed, and the cobalt element in the hydrogenation catalyst S-5 exists in the form of salt. Catalytic converterThe results of analysis of the contents of the components in the reagent are shown in Table 1.

Example 6

The procedure of example 1 was followed except that the reaction was carried out in an open environment during the preparation of the tetrathiomolybdate solution. To obtain hydrogenation catalyst S-6. The results of the analysis of the contents of the components in the catalyst are shown in Table 1.

Example 7

The procedure of example 1 was followed except that nickel was added in an amount of 7mL of nickel acetate solution prepared in a molar ratio of Ni to Mo of 0.1. To obtain hydrogenation catalyst S-7. The results of the analysis of the contents of the components in the catalyst are shown in Table 1.

Example 8

The procedure is as in example 1, except that, during the preparation of the tetrathiomolybdate solution, the reaction is carried out at 60 ℃ for 16 h. To obtain hydrogenation catalyst S-8. The results of the analysis of the contents of the components in the catalyst are shown in Table 1.

Example 9

The procedure of example 1 was followed except that the temperature of the heat treatment during the preparation of the hydrogenation catalyst was 250 ℃. To obtain hydrogenation catalyst S-9. The results of the analysis of the contents of the components in the catalyst are shown in Table 1.

Example 10

The procedure of example 1 was followed except that the temperature of the heat treatment during the preparation of the hydrogenation catalyst was 280 ℃. To obtain the hydrogenation catalyst S-10. The results of the analysis of the contents of the components in the catalyst are shown in Table 1.

Example 11

The procedure of example 4 was followed, except that, in the step (1), not hydrochloric acid but NaOH solution having a concentration of 2mol/L was added dropwise to adjust the pH to 9-9.5, to obtain tetrathiomolybdate solution, which was then concentrated to 8 mL. Hydrogenation catalyst S-11 was obtained, and the results of analysis of the contents of the components in the catalyst are shown in Table 1.

Example 12

The tetrathiomolybdate solution was prepared by charging the materials of example 1, and concentrated to 8mL, and then nickel acetate was weighed in accordance with the amount used in example 1 to prepare 8mL of nickel acetate solution. 10g of the mixture is driedgamma-Al with diameter of 2-5mm₂O₃The carrier is sequentially saturated and impregnated with the tetrathiomolybdate solution and the nickel acetate solution, the impregnation time is 4h each time, and the carrier is dried for 3h at 80 ℃ in a nitrogen atmosphere after each impregnation, so that a composite material A is obtained; then, carrying out heat treatment on the composite material A for 4 hours at 270 ℃ in a nitrogen atmosphere to obtain a hydrogenation catalyst S-12; XRD characterization and analysis are carried out on the hydrogenation catalyst S-12, and MoS appears at the position of 14.2 degrees of 2 theta₃Characteristic dispersion peak of (1), proving that molybdenum in catalyst S-12 is MoS₃The form exists. Under the condition of heat treatment, the nickel salt is not decomposed, and the nickel element in the hydrogenation catalyst S-12 exists in the form of salt. The results of the analysis of the contents of the components in the catalyst are shown in Table 1.

The catalyst does not need to be presulfurized before use, and only needs to be subjected to simple reduction treatment during start-up. Carrying out reduction treatment on the catalysts S-1 to S-12, wherein the reduction treatment conditions are as follows: reducing for 3h at 300 ℃ in a hydrogen atmosphere. The treated catalysts were tested for degree of sulfidation and the results are shown in table 1.

Comparative example 1

Sodium molybdate, nickel acetate and gamma-Al were weighed in the same amounts as in example 1₂O₃The carrier is used for preparing the oxidation type catalyst by adopting a saturated step-by-step impregnation method. Specifically, the method comprises the following steps: dissolving sodium molybdate in 8mL deionized water to prepare a steeping liquid, steeping the carrier for 2h, then placing the carrier in a drying oven to dry for 3h at 120 ℃, heating to 400 ℃ at the speed of 3 ℃/min, and roasting for 3h to obtain Mo/Al₂O₃(ii) a Preparing 7mL of impregnation liquid from nickel acetate, and saturating and impregnating the impregnation liquid in Mo/Al₂O₃Soaking for 4h, drying at 120 deg.C for 3h, heating to 400 deg.C at 3 deg.C/min, and calcining for 3h to obtain NiMo/gamma-Al₂O₃Then 1g of NiMo/gamma-Al is taken₂O₃Loading into a micro hydrogenation reactor for in-situ vulcanization, wherein the vulcanization conditions are as follows: the vulcanization conditions are as follows: the pressure is 4.0MPa, the volume ratio of hydrogen to oil is 1800, the oil inlet flow of the vulcanized oil is 8mL/h, the vulcanization temperature rise program is to heat up to 230 ℃ at the temperature rise rate of 10 ℃/min, keep the temperature for 1h, heat up to 320 ℃ at the temperature rise rate of 10 ℃/min, heat up to 360 ℃ at the temperature rise rate of 1 ℃/min, and heat up to 360℃ at 360 DEG CKeeping the temperature for 105min, and obtaining the catalyst D-1 after vulcanization. The analysis results of the contents of the components in the catalyst and the degree of sulfidation are shown in Table 1.

Comparative example 2

Sodium molybdate, cobalt acetate and gamma-Al were weighed in the same amounts as in example 5₂O₃The carrier is used for preparing the oxidation type catalyst by adopting a saturated step-by-step impregnation method. The specific process is the same as that of comparative example 1, the vulcanization process is the same as that of comparative example 1, and the catalyst D-2 is obtained after the vulcanization is finished. The analysis results of the contents of the components in the catalyst and the degree of sulfidation are shown in Table 1.

Comparative example 3

Mixing sodium molybdate with water, stirring for 40min, adding thioacetamide, stirring for 30min to obtain 40mL solution containing 0.35mol/L sodium molybdate and 1.75mol/L thioacetamide, and mixing with 10g of gamma-Al with diameter of 2-5mm₂O₃Transferring the carrier into an autoclave, heating the autoclave to 95 ℃, reacting for 10h, filtering and washing the suspension, drying for 3h at 80 ℃ under a nitrogen atmosphere, and then performing heat treatment for 4h at 270 ℃ under a nitrogen atmosphere to obtain MoS₂/γ-Al₂O₃7mL of nickel acetate solution is prepared according to the molar ratio of Ni to Mo of 0.5, and saturated and immersed in MoS₂/γ-Al₂O₃The dipping time is 4h, and then the hydrogenation catalyst D-3 is obtained after drying for 3h at 100 ℃ in the nitrogen atmosphere. And (3) carrying out reduction treatment on the catalyst D-3, wherein the reduction treatment conditions are as follows: reducing for 3h at 300 ℃ in a hydrogen atmosphere. The treated catalysts were tested for degree of sulfidation and the results are shown in table 1.

TABLE 1

Examples	Numbering	Metal composition	MoO₃Mass%	NiO (CoO) mass%	Degree of Mo vulcanization%
						1	S-1	NiMo	15.85	3.85	97.6
Comparative example 1	D-1	NiMo	15.87	3.83	70.4
						2	S-2	NiMo	12.43	1.75	96.7
3	S-3	NiMo	22.17	4.56	97.9
						4	S-4	CoMo	12.55	3.28	98.3
5	S-5	CoMo	22.37	5.85	96.9
						Comparative example 2	D-2	CoMo	21.94	5.42	71.2
6	S-6	NiMo	15.55	3.56	77.8
						7	S-7	NiMo	15.84	0.53	97.5
Comparative example 3	D-3	NiMo	7.85	1.26	69.8
						8	S-8	NiMo	15.66	3.52	92.7
9	S-9	NiMo	15.84	3.86	97.5
						10	S-10	NiMo	15.82	3.84	97.6
11	S-11	CoMo	15.79	3.82	98.0
						12	S-12	NiMo	15.82	3.82	97.4

Test examples

In the present test example, the desulfurization activities of the hydrogenation catalyst prepared by the method of the present invention and the hydrogenation catalyst provided in the comparative example were evaluated in accordance with the following methods, and the results were listed.

Hydrodesulfurization: the desulfurization activity of catalysts (S-1 to S-11 and D-3 after reduction treatment, and D-1 and D-2 after sulfidation treatment) was evaluated on a MERYER-07054 continuous high-pressure reaction apparatus manufactured by Merrel laboratory instruments Shanghai Co., Ltd.) using an n-decane solution containing 0.45% by mass of 4, 6-dimethyldibenzothiophene (4, 6-DMDBT). The reaction conditions are as follows: the hydrogen-oil volume ratio is 500 at the temperature of 300 ℃ and under the pressure of 4.0MPa, and the oil inlet flow is 8 mL/h. After the reaction was stabilized for 2 hours, a sample was taken and analyzed by Agilent 7890A gas chromatography, and the activity was expressed as the desulfurization degree of 4,6-DMDBT, and the results are shown in Table 2.

The reaction desulfurization rate X was calculated as follows:

x ═ 100% of raw oil sulfur content-product oil sulfur content)/raw oil sulfur content

TABLE 2

Examples	Numbering	Metal composition	Desulfurization degree%
				1	S-1	NiMo	99.8
Comparative example 1	D-1	NiMo	93.2
				2	S-2	NiMo	99.7
3	S-3	NiMo	99.8
				4	S-4	CoMo	99.8
5	S-5	CoMo	99.9
				6	S-6	NiMo	95.3
7	S-7	NiMo	89.3
				Comparative example 3	D-3	NiMo	87.4
8	S-8	NiMo	97.5
				9	S-9	NiMo	98.7
10	S-10	NiMo	97.5
				11	S-11	CoMo	99.7
12	S-12	NiMo	99.7

As can be seen from the results in tables 1 and 2, compared with the hydrogenation catalyst prepared by the conventional method, the hydrogenation catalyst provided by the present invention can almost completely sulfurize the main active component by simple reduction treatment, and the utilization rate of the active metal is sufficiently improved. The above results fully indicate that the preparation method of the hydrogenation catalyst provided by the invention has incomparable advantages compared with the conventional impregnation method. In addition, under the preferable condition, the self-made tetrathiomolybdate solution is adopted as the impregnation liquid, so that the processes of purifying and crystallizing the tetrathiomolybdate solution and dissolving the tetrathiomolybdate are omitted, and the defect that the production cost of the vulcanization type hydrogenation catalyst is high in the prior art is overcome.

The preferred embodiments of the present invention have been described in detail, however, the present invention is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications are within the protective scope of the present invention.

It should be noted that the various features described in the above embodiments may be combined in any suitable manner without departing from the scope of the invention. The invention is not described in detail in order to avoid unnecessary repetition.

In addition, any combination of the various embodiments of the present invention is also possible, and the same should be considered as the disclosure of the present invention as long as it does not depart from the spirit of the present invention.

Claims

1. A preparation method of a hydrogenation catalyst comprises the following steps:

(1) introducing tetrathiomolybdate and VIII group metal salt onto a carrier to obtain a composite material A;

(2) carrying out heat treatment on the composite material A under an inert atmosphere or a reducing atmosphere, wherein the heat treatment enables Mo in the composite material A to exist in a trisulfide form and a VIII group metal element to exist in a salt form;

the method for introducing tetrathiomolybdate and the group VIII metal salt onto the carrier in the step (1) comprises the following steps: preparing a tetrathiomolybdate solution, adding a group VIII metal salt to the tetrathiomolybdate solution to form a mixed solution, impregnating the carrier with the mixed solution, and then drying the impregnated carrier; or respectively adopting tetrathiomolybdate solution and solution containing VIII group metal salt to impregnate the carrier, and drying after each impregnation; the group VIII metal salt is selected from one or more of nitrate, carbonate, chloride, sulfate and acetate of cobalt and/or nickel;

the tetrathiomolybdate solution is prepared by the following method:

b) reacting the mixture obtained in step a) for 2-24h at 50-100 ℃ and/or pH 5-10; the organic sulfur source is a sulfur-containing material capable of being hydrolyzed under the conditions of step a) and/or step b).

2. The method according to claim 1, wherein the tetrathiomolybdate solution has a concentration of 0.2 to 1.8 mol/L.

3. The method according to claim 2, wherein the tetrathiomolybdate solution has a concentration of 0.3 to 1.2 mol/L.

4. The production method according to claim 1,

step a) the mixing comprises: the molybdenum-containing compound is dissolved in water to form a first solution, and then a source of organic sulfur is added to the first solution.

5. The production method according to claim 4, wherein the concentration of the molybdenum-containing compound in the first solution is 0.2 to 0.5mol/L in terms of Mo element.

6. The production method according to claim 4, wherein the molar ratio of the organic sulfur source in terms of sulfur element to the molybdenum-containing compound in terms of molybdenum element is 4 to 6: 1.

7. the process according to any one of claims 1 to 6, wherein the mixture obtained in step a) is reacted at from 70 to 100 ℃ for from 2 to 24h, or

Reacting at pH 5-6 for 2-24h, or

Reacting for 2-24h under the condition that the pH value is 8-10.

8. The process according to claim 7, wherein the mixture obtained in step a) is reacted at 70-100 ℃ for 10-16h, or

Reacting at pH 5-6 for 3-7h, or

Reacting for 3-7h under the condition that the pH value is 8-10.

9. The production method according to claim 8, wherein the reaction is carried out under a closed condition.

10. The production method according to any one of claims 1 to 6 or 8 to 9, wherein the pH is adjusted in step b) by adding an acid and/or a base to the mixture; the acid is selected from at least one of hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, formic acid and acetic acid; the alkali is at least one selected from ammonia water, sodium hydroxide and potassium hydroxide.

11. The production method according to any one of claims 1 to 6 and 8 to 9, wherein the molybdenum-containing compound is at least one selected from the group consisting of sodium molybdate, ammonium paramolybdate, ammonium phosphomolybdate and molybdenum trioxide;

the organic sulfur source is at least one selected from L-cysteine, thioamide shown in a formula (1), monothioester shown in a formula (2) and dithioester shown in a formula (3),

in the formula (1), R¹Is NH₂-、CH₃-、CH₃CH₂-、CH₃NH-or (CH)₃)₂N-，R²And R³Each independently is H or C1-C4 alkyl;

in the formula (2), R⁴Is H or C1-C4 alkyl, R⁵Is C1-C4 alkyl;

in the formula (3), R⁶Is H or C1-C4 alkyl, R⁷Is C1-C4 alkyl.

12. The process according to claim 11, wherein the organic sulfur source is thiourea and/or thioacetamide.

13. The production method according to any one of claims 1 to 6, 8 to 9, and 12, wherein the concentration of the group VIII metal salt in the mixed solution or the group VIII metal salt-containing solution is 0.1 to 1 mol/L;

the tetrathiomolybdate, the VIII group metal salt and the carrier are used in such amounts that the carrier is present in an amount of 59 to 90 wt%, the VIII group metal element is present in an amount of 1 to 15 wt% and Mo is present in an amount of 5 to 40 wt%, calculated as an oxide, based on the total amount of the catalyst.

14. The production method according to any one of claims 1 to 6, 8 to 9 and 12, wherein the molar ratio of the group VIII metal salt to tetrathiomolybdate in terms of metal element is 0.1 to 1.

15. The method according to claim 1, wherein the group VIII metal salt is used in a molar ratio of the metal element to the tetrathiomolybdate of 0.2 to 0.5.

16. The production method according to any one of claims 1 to 6, 8 to 9, 12 and 15, wherein in the step (1), the drying conditions include: the temperature is 80-120 ℃, and the time is 2-8 h.

17. The production method according to claim 16, wherein in the step (1), the drying conditions include: the temperature is 80-100 ℃ and the time is 3-6 h.

18. The production method according to any one of claims 1 to 6, 8 to 9, 12, 15 and 17, wherein in the step (2), the inert atmosphere is provided by one or more of nitrogen, argon and helium, and the reducing atmosphere is provided by hydrogen and/or hydrogen sulfide and optionally an inert gas;

under inert atmosphere, the conditions of the heat treatment comprise: the temperature is 250 ℃ and 300 ℃, and the time is 2-8 h; under a reducing atmosphere, the heat treatment conditions comprise: the temperature is 200 ℃ and 250 ℃, and the time is 2-8 h.

19. The method of claim 18, wherein the heat treatment conditions include, under an inert atmosphere: the temperature is 260-270 ℃ and the time is 3-6 h;

under a reducing atmosphere, the heat treatment conditions comprise: the temperature is 200 ℃ and 230 ℃, and the time is 3-6 h.

20. The production process according to any one of claims 1 to 6, 8 to 9, 12, 15, 17, 19, wherein the carrier is selected from one or more of γ -alumina, silica, alumina-silica, titania, magnesia, silica-zirconia, silica-thoria, silica-beryllia, silica-titania, titania-zirconia, silica-alumina-thoria, silica-alumina-titania, silica-alumina-magnesia and silica-alumina-zirconia.

21. A hydrogenation catalyst produced by the production method according to any one of claims 1 to 6, 8 to 9, 12, 15, 17 and 19.

22. Use of a hydrogenation catalyst as claimed in claim 21 in hydrodesulphurisation.