CN107961773B

CN107961773B - Hydrodesulfurization catalyst, preparation method thereof and preparation method of vulcanized hydrodesulfurization catalyst

Info

Publication number: CN107961773B
Application number: CN201610916418.6A
Authority: CN
Inventors: 陈文斌; 赵新强; 刘学芬; 贾燕子; 杨清河; 聂红; 李大东; 邓中活; 施瑢
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: 2016-10-20
Filing date: 2016-10-20
Publication date: 2020-12-04
Anticipated expiration: 2036-10-20
Also published as: CN107961773A

Abstract

The invention provides a hydrodesulfurization catalyst, a sulfided hydrodesulfurization catalyst and a preparation method thereof. The preparation method of the hydrodesulfurization catalyst comprises the steps of loading the hydrodesulfurization catalytic active metal component and one or more organic matters with the molecular weight less than 80 on a carrier in sequence, and then drying under specific conditions. When the hydrodesulfurization catalyst prepared by the method is used, the oxidation state catalyst is directly converted into the vulcanization state catalyst by adopting a temperature programming vulcanization method without a drying stage. The invention can obtain the hydrodesulfurization catalyst which has higher hydrodesulfurization activity and can treat the residual oil with poorer quality.

Description

Hydrodesulfurization catalyst, preparation method thereof and preparation method of vulcanized hydrodesulfurization catalyst

Technical Field

The invention relates to a preparation method of a hydrodesulfurization catalyst, and a hydrodesulfurization catalyst and a preparation method of a vulcanized hydrodesulfurization catalyst prepared by the method.

Background

The world trend of crude oil changes shows that the quantity of light oil is gradually reduced, the quantity of heavy oil is gradually increased, and the deterioration is intensified, and the gradual increase of refining of heavy/poor oil is a problem generally faced by oil refining enterprises at home and abroad in recent years. The heavy oil lightening technology is widely regarded, and the combination of fixed bed hydrotreatment and catalytic cracking (RFCC) of the residual oil is the main technology for treating heavy oil in the current oil refinery, so that 80% of crude oil produced in the world can be processed in the refinery. The residual oil hydrogenation technology which is one of the cores can remove most of impurities such as metal, sulfur, nitrogen and the like in the residual oil, and provides a suitable raw material for downstream RFCC. Refineries are mixing more and more inferior residues in the plant in order to increase the economic efficiency. The poorer the feedstock, the higher the sulfur, asphaltene and gum content therein, giving greater pressure to the residue hydrotreater. Due to the increasingly poor quality of the residual oil and the increasingly strict future environmental standards, the desulfurization activity of the catalyst needs to be higher to meet the future requirements.

Generally speaking, hydrogenation catalysts have as the main active component a sulphide of a group VIB metal (Mo and/or W) and as the Co-active component a sulphide of a group VIII metal (Co and/or Ni). The sulfided hydrogenation catalyst is generally prepared by reacting an oxidized hydrogenation catalyst with a sulfided medium to convert the metal component of the hydrogenation catalyst from an oxidized state to a sulfided state, wherein the sulfided metal is the active center of the corresponding hydrogenation catalyst.

In order to improve the activity of the hydrodesulfurization catalyst, CN200810115862 discloses a heavy oil hydrotreating catalyst and a preparation method thereofThe pore volume of the carrier is 0.6-1.2ml/g, the specific surface is 200-²The average pore diameter is 11-14nm, and the pore volume of pores with the pore diameter of 9-15 nm accounts for 80-95% of the total pore volume. The preparation method of the carrier comprises the steps of forming, drying and roasting the alumina precursor, wherein the roasting condition is that the alumina precursor is roasted at the temperature of 350-400 ℃ for 0.5-2 hours, and then roasted at the temperature of 600-800 ℃ for 1-6 hours.

CN201210427895 discloses a hydrodemetallization catalyst and a preparation method thereof, wherein the specific surface area of the catalyst is 90-120m²The pore volume is 0.8-1.2ml/g, and the optional pore diameter is 40-60 nm. The pore diameter of more than 30nm in the pore distribution accounts for 60-90% of the total pore volume.

CN96120423 discloses a residual oil hydrotreating catalyst and a preparation method thereof, which uses gamma-Al₂O₃Is a carrier for loading metal elements of VIII group and VIB group, and is characterized in that the pore volume of the catalyst is 0.30-0.60mL/g, and the specific surface is 120-200m²(ii)/g, the average pore diameter is 9.0-13.0nm, and the ratio of the pore volume of the pore diameter of 7.0-13.0nm to the total pore volume is more than 80%.

Although the above method has a certain improvement on the desulfurization activity of the catalyst, the method is not enough for poor-quality residual oil, and the hydrodesulfurization activity of the catalyst needs to be further improved to adapt to the processing of the residual oil with increasingly poor quality.

Disclosure of Invention

The invention aims to further improve the desulfurization performance of a hydrodesulfurization catalyst, and provides a hydrodesulfurization catalyst with higher hydrodesulfurization activity, a preparation method of the hydrodesulfurization catalyst and a preparation method of a sulfurized hydrodesulfurization catalyst.

The invention provides a preparation method of a hydrodesulfurization catalyst, which comprises the steps of sequentially loading a hydrodesulfurization catalytic active metal component and one or more organic matters with the molecular weight of less than 80 on a carrier, and then drying, wherein the water absorption of the carrier is not less than 0.9mL/g, the pore volume with the pore diameter of 2-8nm in the carrier accounts for no more than 35% of the total pore volume, and the pore volume with the pore diameter of 2-6nm accounts for no more than 15% of the total pore volume; the drying is carried out at a temperature of 50-80 ℃ for 1-15 h.

The invention also provides a hydrodesulfurization catalyst prepared by the method.

The invention also provides a preparation method of the vulcanized hydrodesulfurization catalyst, which comprises the steps of preparing the hydrodesulfurization catalyst by adopting the method, and then directly raising the temperature by program for vulcanization without drying the hydrodesulfurization catalyst.

According to the preparation method of the hydrodesulfurization catalyst, the specific carrier is adopted, one or more organic matters with the molecular weight less than 80 are loaded after the hydrodesulfurization catalytic activity metal component is loaded, and then the carrier impregnated with the organic matters is dried under the specific condition, so that the obtained hydrodesulfurization catalyst can be directly heated for vulcanization without drying, and the vulcanized hydrodesulfurization catalyst with the hydrodesulfurization activity obviously improved can be obtained, and therefore, the hydrodesulfurization activity of the catalyst is improved, the preparation process is shortened, the time is saved, and the energy consumption is reduced. The invention can obtain the hydrodesulfurization catalyst which has higher hydrodesulfurization activity and can treat the residual oil with poorer quality. In the embodiment, after the hydrodesulfurization catalyst prepared by the preparation method of the hydrodesulfurization catalyst provided by the invention is used for hydrodesulfurization treatment of vacuum residue with the sulfur content of 3.5 wt%, the sulfur content can be reduced to about 0.2 wt%, and the desulfurization rate is as high as 94%.

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

Detailed Description

The following describes in detail specific embodiments of the present invention. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.

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.

According to the invention, the water absorption of the carrier is 0.95-1.4mL/g, the pore volume of the carrier with the pore diameter of 2-8nm accounts for 15-30% of the total pore volume, and the pore volume of the carrier with the pore diameter of 2-6nm accounts for 5-10% of the total pore volume. By selecting the carrier with larger aperture, when the content of active metal is higher, the pore channel is not easy to block, more diffusion space can be provided for catalytic reaction, and the purpose of improving the activity of the catalyst is achieved. Especially for heavier and inferior oil such as residual oil, is more effective than the conventional catalyst.

In the present invention, the method for measuring the water absorption of the catalyst carrier is: the support (by weight) was immersed in water (by volume) for 2 hours at a ratio of support (by weight) to water (by volume) of 1: and 3, separating the carrier after water absorption from water, and calculating the water absorption volume of the carrier, wherein the water absorption rate of the carrier is the water absorption volume of the carrier/weight of the carrier.

Various pore diameters and pore volumes of the carrier were measured by low-temperature nitrogen adsorption (see methods of analysis of petrochemical industry (RIPP), eds of Yangshui et al, published by scientific Press, 1990).

The kind of the carrier is not particularly limited, and they may be commercially available ones or may be prepared by any conventional method. Preferred supports are selected from one or more of alumina, silica-alumina, aluminium silicate, silica, titania, zirconia, activated carbon. Wherein, the alumina can be one or more of gamma-alumina, eta-alumina, theta-alumina, -alumina and chi-alumina. According to the method provided by the invention, the carrier of the catalyst can be made into various easily-operated molded objects according to different requirements, such as spheres, tablets, cloverleaf shapes or strips. The molding is prepared by conventional methods, such as extrusion molding. When the extrusion molding method is adopted for molding, a proper amount of extrusion aid and/or peptizing agent can be added, and then the extrusion molding is carried out.

The carrier can be obtained by various conventional methods, for example, by mixing pseudo-boehmite powder and/or silica-alumina powder having a pore volume of 0.9 to 1.4mL/g with a peptizer and an extrusion aid with water, and then molding the carrier by extrusion. The extrusion aid can be one or more of sesbania powder, methyl cellulose and starch. The peptizing agent is one or more of nitric acid, citric acid and acetic acid. Powder: the ratio of water to the assistant to the peptizing agent is 1:1.05-1.55:0.005-0.06: 0.005-0.05. In the above proportions, the solid is in terms of mass (g), the liquid is in terms of volume (mL), and the peptizing agent is a commercially available concentrated acid. Drying the carrier obtained by extruding at 50-200 ℃ for 1-10h, and then roasting at 500-900 ℃ for 1-10h to obtain the final carrier. The carriers with different pore volumes and pore size distributions can be obtained by adjusting the amounts of the powder, the peptizing agent and the water and the roasting temperature.

Before the forming on the extruder, Si, B, Mg, P, F, Zn and other elements can be introduced into the powder.

According to the invention, the hydrodesulfurization catalytically active metal component contains a group VIB metal element and a group VIII metal element, wherein the molecular atomic ratio of the organic substance having a molecular weight of less than 80 to the group VIII metal element (i.e. the molar ratio of the organic substance having a molecular weight of less than 80 to the group VIII metal element) is preferably 0.2 to 5, more preferably 0.5 to 3.

According to the invention, the organic substances having a molecular weight of less than 80 can be of any molecular weight of less than 80, preferably not more than 75, and contain-OH, -NH₂and-COOH, preferably not including an amide-based substance such as urea, and more preferably one or more of methanol, ethanol, propanol, isopropanol, butanol, isobutanol, ethylene glycol, formic acid, acetic acid, propionic acid, ethylenediamine, ethanolamine, ethylamine, propylamine, butylamine, and glycine. The nitrogen-containing organic substance is preferably an alcohol or a carboxylic acid because of its toxicity.

According to a preferred embodiment of the present invention, the preparation process of the impregnation solution used in step (1) comprises adding the precursor containing the group VIB metal element and the group VIII metal to the aqueous solution of the phosphorus-containing substance and/or ammonia under stirring, and stirring at 40-100 ℃, preferably 50-90 ℃, preferably at constant temperature for 1-8h, preferably 2-6h, until all the precursor is dissolved.

According to the invention, the impregnation liquor contains the group VIB metal elements and the group VIII metal elements in such a way that the group VIII metal element content is between 1 and 15 wt.%, preferably between 3 and 10 wt.%, calculated as oxides, based on the dry weight of the catalyst obtained; the content of group VIB metal elements is from 5 to 60% by weight, preferably from 10 to 45% by weight.

In the present invention, the dry weight is the weight determined by baking the sample at 600 ℃ for 4 hours.

Examples of the group VIII metal element include, but are not limited to, one or more of iron, cobalt, nickel, ruthenium, rhodium, and palladium. Examples of the group VIB metal elements include, but are not limited to, one or more of chromium, molybdenum, and tungsten. The above metal active components can be obtained in the catalyst by adding their precursors to the impregnation solution. The cobalt precursor includes but is not limited to one or more of cobalt nitrate, basic cobalt carbonate, cobalt acetate and cobalt oxide, the Mo precursor includes but is not limited to one or more of ammonium heptamolybdate, ammonium molybdate, ammonium phosphomolybdate and molybdenum oxide, the Ni precursor includes but is not limited to one or more of nickel nitrate, basic nickel carbonate, nickel acetate and nickel oxide, and the tungsten precursor includes but is not limited to one or more of ammonium metatungstate, ammonium ethylmetatungstate and tungsten oxide.

According to the method provided by the invention, the impregnation liquid contains phosphorus-containing substances and/or ammonia, wherein the phosphorus-containing substances include but are not limited to one or more of phosphoric acid, hypophosphorous acid, ammonium phosphate and ammonium dihydrogen phosphate.

The phosphorus-containing material is used in an amount such that P is present on a dry weight basis in the final catalyst₂O₅The content of phosphorus element is 0.5-8 wt%. The concentration of ammonia ranges from 10 to 25% by weight. The dosage of the ammonia water is based on the solvent required by the impregnating solution.

The impregnation method of the present invention is not particularly limited, and the impregnation can be carried out in various ways known to those skilled in the art. For example, by dipping, spraying, etc., the specific process is well known to those skilled in the art and will not be described herein.

According to a preferred embodiment of the present invention, said drying of step (2) is carried out at 55-75 ℃ for 2-8 h. Slowly drying the mixture of the impregnation liquid and the carrier at 50-80 deg.C, preferably 55-75 deg.C for 1-15h, preferably 2-8h to obtain catalyst dry strip. In general, the conventional catalyst preparation method is dried at a temperature of 90 ℃ or more, and the inventors of the present invention have found in the course of their studies that the color of the catalyst obtained after drying is greatly different as the drying temperature increases, for example, a CoMo type catalyst gives a dark gray color when dried at 120 ℃ and a light red color when dried at 60 to 80 ℃. Further by comparison, the catalyst dried at a lower temperature has a higher catalytic activity. This is probably because the Co atoms can be kept in a better dispersed state at a lower drying temperature, thereby improving the catalytic performance. In addition, at lower drying temperature, more organic matters can be retained in the catalyst, and the better effect is achieved in the vulcanization process.

Compared with the traditional catalyst, the catalyst prepared by the invention has the advantages that the drying temperature and organic matters in the step (2) are lower, the energy consumption can be saved, the catalyst cost can be reduced, and the carbon emission can be reduced.

According to the present invention, the drying of step (1) may be carried out under conventional catalyst drying conditions, preferably, the drying conditions of step (1) include a drying temperature of 90 to 200 ℃ for 2 to 8 hours.

The invention also provides a hydrodesulfurization catalyst prepared by the method. The hydrodesulfurization catalyst prepared by the method has higher catalytic activity, can be used for residual oil hydrodesulfurization and distillate oil hydrodesulfurization, and the sulfur content of the obtained product is obviously lower than that of an oil product treated by the catalyst in the prior art.

The hydrodesulfurization catalyst produced by the above process is in an oxidized state, and as is known to those skilled in the art, hydrodesulfurization requires conversion of the oxidized catalyst to a sulfided state. Generally, after the metal component is loaded by an impregnation method, the metal component is dried or is dried and then is further calcined to obtain the oxidation state catalyst. The oxidation state catalyst can be sold in the market or transferred to an oil product processing place for hydrodesulfurization application. Before hydrodesulfurization, the oxidation state catalyst generally needs to be dried, then temperature programming is carried out, and vulcanization is carried out after reaching the vulcanization temperature. The inventor of the invention finds that the oxidation state catalyst obtained by the method of the invention can be directly subjected to temperature programming without drying, and vulcanization can be carried out after reaching the vulcanization temperature. Therefore, compared with the oxidation state hydrodesulfurization catalyst in the prior art, the oxidation state hydrodesulfurization catalyst obtained by the method can be directly subjected to temperature programming for vulcanization without drying, so that the drying step is saved, the process time is saved, and the energy consumption caused by the process time is reduced. Moreover, the catalyst obtained by the method has higher hydrodesulfurization activity.

Therefore, the invention provides a preparation method of a vulcanized hydrodesulfurization catalyst, which comprises the steps of preparing the hydrodesulfurization catalyst (in an oxidation state) by adopting the method, and then directly raising the temperature by a program to carry out vulcanization on the hydrodesulfurization catalyst without drying. The vulcanization mode is not particularly limited, and may be dry vulcanization or wet vulcanization.

According to one embodiment of the invention, the temperature rise rate of the temperature programming is 5-60 ℃/h, the vulcanization temperature is 280-420 ℃, the vulcanization pressure is 0.1-15MPa, and the volume space velocity is 0.5-20 h^-1The volume ratio of hydrogen to oil is 100-: 1. the temperature programming can be firstly constant at the temperature of 200 ℃ and 250 ℃ for 2-8h, and then the temperature is raised to the temperature of 300 ℃ and 400 ℃ for vulcanization for 5-10 h. The rate of temperature rise in each stage may be in the range of 5-50 deg.C/h.

The following examples further illustrate the invention.

In the following examples, the composition of the catalyst was calculated from the amount of charge, and the pore distribution, pore diameter, pore volume (pore volume), and specific surface area of the catalyst and the carrier were measured by low-temperature nitrogen adsorption (see, "analysis of petrochemical industry (RIPP test method)", edited by yan cui, published by scientific publishers, 1990).

The evaluation of the hydrodesulfurization activity of the catalysts of examples 1 to 6 and of comparative examples 1 to 5 was carried out on a 200mL medium-sized apparatus, without passing through a drying stage during the test, by converting the catalyst in the oxidized state directly into sulfur by means of the temperature-programmed vulcanization processA state catalyst. The vulcanization conditions are as follows: the vulcanization pressure was 14.0MPa and the vulcanized oil contained 2 wt% CS₂The volume space velocity of the kerosene is 1.2h^-1And the hydrogen-oil ratio is 400v/v, the constant temperature is kept for 6h at 230 ℃/h, then the temperature is raised to 360 ℃ for vulcanization for 8h, and the temperature raising rate of each stage is 10 ℃/h. And after vulcanization, switching reaction raw materials to perform residual oil hydrodesulfurization activity test, wherein the raw material oil is the Caragana sand light pressure reduction residual oil, the mass fraction of sulfur is 3.5%, and the mass fraction of carbon residue is 12.0%. 50mL of demetallizing agent (RDM-32, produced by China petrochemical Long-distance catalyst plant) and 150mL of catalyst to be evaluated were charged in the reactor, respectively. The reaction temperature, the pressure, the volume space velocity and the hydrogen-oil ratio are respectively 380 ℃, 14.0MPa and 0.5h^-1And 700 v/v. After the reaction was stabilized (100 hours), the product was analyzed for the mass fraction of sulfur using SLFA-6800 sulfur meter manufactured by HORIBA Corp.

The evaluation of the hydrodesulphurisation activity of the catalysts of examples 7 and 8 was carried out on a 20mL high pressure micro-reactor, without passing through the drying stage during the test, by directly converting the catalyst in the oxidic state into the catalyst in the sulphidic state by means of temperature programmed sulphidation. The vulcanization conditions are as follows: the vulcanization pressure is 6.4MPa, and the vulcanized oil contains 2 wt% of CS₂The volume space velocity of the kerosene is 2h^-1And the hydrogen-oil ratio is 300v/v, the constant temperature is kept for 6h at 230 ℃/h, then the temperature is raised to 360 ℃ for vulcanization for 8h, and the temperature raising rate of each stage is 10 ℃/h. And after vulcanization, switching reaction raw materials to carry out hydrodesulfurization activity test, wherein the reaction raw materials are poor distillate oil with the sulfur content of 11000ppm and the nitrogen content of 265 ppm. The test conditions were: the pressure is 6.4MPa, and the volume space velocity is 2h^-1The hydrogen-oil ratio was 300v/v and the reaction temperature was 350 ℃. After the reaction was stabilized (100h), the mass fraction of sulfur in the product was analyzed using a sulfur-nitrogen analyzer (model number TN/TS3000, available from seimer feishi).

Preparation example 1

The pseudo-boehmite powder produced by the catalyst factory in the long mountains of the petrochemical industry in China is mixed with peptizer and extrusion aid by adding water, and then the carrier is molded by adopting a strip extrusion mode. The pore volume of the powder is 0.95mL/g, the weight ratio of the powder to the assistant extruded sesbania powder is 1:0.002, the weight ratio of the powder to the peptizer nitric acid is 1:0.0015, the weight ratio of the powder to the water is 1:1.23, the roasting temperature is 750 ℃, and the roasting time is 3 hours. The obtained alumina-1 has the water absorption of 0.96mL/g, the proportion of the pore volume with the pore diameter range of 2-8nm in the total pore volume is 30%, and the proportion of the pore volume with the pore diameter range of 2-6nm in the total pore volume is 10%.

Preparation example 2

The pseudo-boehmite powder produced by the catalyst factory in the long mountains of the petrochemical industry in China is mixed with peptizer and extrusion aid by adding water, and then the carrier is molded by adopting a strip extrusion mode. The pore volume of the powder is 1.2mL/g, the weight ratio of the powder to the assistant extruded sesbania powder is 1:0.0015, the weight ratio of the powder to the peptizer nitric acid is 1:0.001, the weight ratio of the acid to the water is 1:1.4, the roasting temperature is 700 ℃, and the roasting time is 4 hours. The alumina-2 is obtained, the water absorption of the alumina-2 is 1.2mL/g, the proportion of the pore volume with the pore diameter range of 2-8nm in the total pore volume is 15%, and the proportion of the pore volume with the pore diameter range of 2-6nm in the total pore volume is 5%.

Preparation example 3

The pseudo-boehmite powder produced by the catalyst factory in the long mountains of the petrochemical industry in China is mixed with peptizer and extrusion aid by adding water, and then the carrier is molded by adopting a strip extrusion mode. The pore volume of the powder is 1.0mL/g, the weight ratio of the powder to the assistant extruded sesbania powder is 1:0.0025, the weight ratio of the powder to the peptizer nitric acid is 1:0.002, the weight ratio of the acid to the water is 1:1.3, the roasting temperature is 650 ℃, and the roasting time is 3 hours. The alumina-3 is obtained, the water absorption of the alumina-3 is 1.2mL/g, the proportion of the pore volume with the pore diameter range of 2-8nm in the total pore volume is 25%, and the proportion of the pore volume with the pore diameter range of 2-6nm in the total pore volume is 8%.

Preparation example 4

An alumina carrier was prepared according to the method of preparation example 3, except that the pore volume was 0.8mL/g, the weight ratio of the pseudo-boehmite powder to the adjuvant sesbania powder was 1:0.003, the weight ratio of the powder to the peptizer nitric acid was 1:0.0035, the weight ratio of the acid to water was 1:0.9, the calcination temperature was 600 ℃, the calcination time was 3 hours, and alumina-4 was obtained, the water absorption of alumina-4 was 0.85mL/g, the proportion of pore volume in the pore diameter range of 2-8nm to the total pore volume was 45%, and the proportion of pore volume in the pore diameter range of 2-6nm to the total pore volume was 25%.

Example 1

(1) The method comprises the steps of preparing an impregnation solution by using ammonia water, ammonium heptamolybdate and cobalt nitrate as raw materials. The concentration of ammonia was 18% by weight. Impregnating alumina-1 with the impregnating solution by an isometric impregnation method, and then drying at 90 ℃ for 8 hours;

(2) and (2) dipping the product obtained in the step (1) into an aqueous solution of ethylenediamine by an isometric dipping method, and then drying at 60 ℃ for 3 hours to obtain the oxidation state catalyst. Wherein, based on the dry weight of the catalyst and calculated by oxide, the content of molybdenum is 14.5 percent, the content of cobalt is 3.5 percent, and the molar ratio of the ethylenediamine to the cobalt is 2: 1. after the catalyst was subjected to sulfiding and reaction testing, the sulfur content of the resulting product was 0.25 wt%.

Comparative example 1

A catalyst was prepared as in example 1 except that the impregnated product was dried at 120 ℃ for 3h to give an oxidized form catalyst. After the catalyst is subjected to vulcanization and reaction test, the sulfur content of the obtained product is 0.35 weight percent. It can be seen that low temperature drying can improve the hydrodesulphurisation performance of the catalyst.

Example 2

(1) Preparing a dipping solution by using phosphoric acid, molybdenum oxide and basic nickel carbonate as raw materials, dipping alumina-2 by using the dipping solution by using an isometric dipping method, and then drying for 5 hours at 150 ℃;

(2) and (2) soaking the product obtained in the step (1) in an ethylene glycol aqueous solution by adopting an isometric soaking method, and then drying at 80 ℃ for 5 hours to obtain the oxidation state catalyst. Wherein, based on the dry weight of the catalyst and calculated by oxide, the content of molybdenum is 16.5 percent, the content of nickel is 4.5 percent, the content of P is 4 percent, and the molar ratio of ethylene glycol to nickel is 3: 1. After the catalyst is subjected to vulcanization and reaction test, the sulfur content of the obtained product is 0.22 wt%.

Comparative example 2

A catalyst was prepared as in example 2 except that the impregnated product was dried at 120 ℃ for 5h to give an oxidized form catalyst. After the catalyst is subjected to vulcanization and reaction test, the sulfur content of the obtained product is 0.27 weight percent.

Example 3

A catalyst was prepared according to the method of example 2, except that the amount of ethylene glycol used in the preparation of the catalyst was increased to change the molar ratio of ethylene glycol to nickel to 5:1, to prepare an oxidized form catalyst. The sulfur content of the product obtained by the activity test was 0.28 wt%.

Comparing example 3 with example 2, it can be seen that too high an organic content is also detrimental to the activity of the catalyst.

Comparative example 3

A catalyst was prepared according to the procedure of example 2, except that the organic ethylene glycol was replaced by the same weight of citric acid in the preparation of the catalyst, to obtain an oxidized form of the catalyst. After activity testing, the sulfur content of the product is 0.51 weight percent.

Comparing example 3 with comparative example 3, it can be seen that the catalyst prepared by using the organic substance having a molecular weight of less than 80 has better desulfurization performance.

Example 4

(1) Preparing a dipping solution by using phosphoric acid, molybdenum oxide and basic nickel carbonate as raw materials, dipping alumina-3 by using the dipping solution by using an isometric dipping method, and then drying for 2 hours at 200 ℃;

(2) and (2) dipping the product obtained in the step (1) into a propanol aqueous solution by adopting an isometric dipping method, and then drying at 50 ℃ for 8h to obtain the catalyst. Wherein, based on the dry weight of the catalyst and calculated by oxide, the content of molybdenum in the catalyst is 18.0 percent, the content of nickel oxide is 3.0 percent, the content of P is 4.0 percent, and the molar ratio of propanol to nickel is 0.5: 1. After the catalyst is subjected to vulcanization and reaction test, the sulfur content of the obtained product is 0.20 weight percent.

Comparative example 4

A catalyst was prepared as in example 4 except that the impregnated product was dried at 120 ℃ for 8h to give an oxidized form catalyst. The same activity test method was used for vulcanization and activity testing to obtain a product with a sulfur content of 0.28 wt.%.

Comparing the results of example 4 with those of comparative example 4, it can be seen that low temperature drying can improve the hydrodesulfurization performance of the catalyst.

Comparative example 5

A catalyst was prepared by following the procedure of example 4, except that the carrier was replaced with alumina-4 to obtain an oxidized form catalyst. The catalyst was tested for activity and the product sulfur content was 0.53 wt%.

Comparing example 4 with comparative example 5, it can be seen that the catalyst of the present invention has higher catalytic activity when pore volume in the pore size range of 2-8nm is selected to be smaller.

Example 5

A catalyst was prepared according to the procedure of example 4 except that the organic propanol in the preparation of the catalyst was replaced by the same weight of glycine to give the catalyst in the oxidized state. After activity testing, the sulfur content of the product is 0.22 wt%.

Example 6

A catalyst was prepared according to the procedure of example 4, except that the organic propanol was replaced by the same weight of ethanolamine in the preparation of the catalyst to obtain an oxidized form catalyst. After activity testing, the sulfur content of the product is 0.25 weight percent.

Example 7

(1) Preparing a dipping solution by using phosphoric acid, molybdenum oxide and basic nickel carbonate as raw materials, dipping alumina-2 by using the dipping solution by using an isometric dipping method, and then drying for 2 hours at 200 ℃;

(2) and (2) soaking the product obtained in the step (1) in an ethylene glycol aqueous solution by adopting an isometric soaking method, and then drying at 80 ℃ for 5 hours to obtain the oxidation state catalyst. Wherein, based on the dry weight of the catalyst and calculated by oxide, the content of molybdenum is 45 percent, the content of nickel is 9.0 percent, the content of P is 8.0 percent, and the molar ratio of ethylene glycol to nickel is 3: 1. The sulfur content of the obtained product is 5ppm after the catalyst is subjected to vulcanization and reaction test.

Example 8

(2) and (2) dipping the product obtained in the step (1) into a propanol aqueous solution by adopting an isometric dipping method, and then drying at 50 ℃ for 8h to obtain the catalyst. Wherein, based on the dry weight of the catalyst and calculated by oxide, the molybdenum content in the catalyst is 26 percent, the nickel content is 4.5 percent, the P content is 4.0 percent, and the molar ratio of propanol to nickel is 0.5: 1. The sulfur content of the obtained product is 5.5ppm after the catalyst is subjected to vulcanization and reaction test.

In conclusion, the method provided by the invention can improve the performance of the residual oil hydrodesulfurization catalyst, is simple in preparation method, can reduce the cost of the catalyst, and has good industrial application prospect.

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 hydrodesulfurization catalyst comprises the steps of sequentially loading a hydrodesulfurization catalytic activity metal component and one or more organic matters with the molecular weight of less than 80 on a carrier, and then drying, wherein the water absorption of the carrier is not less than 0.9mL/g, the pore volume of the carrier with the pore diameter of 2-8nm accounts for no more than 35% of the total pore volume, and the pore volume of the carrier with the pore diameter of 2-6nm accounts for no more than 15% of the total pore volume; the drying is carried out for 1 to 15 hours at the temperature of 50 to 80 ℃;

the organic matter with the molecular weight less than 80 contains-OH and-NH₂Any one of, -COOH, and the organic matter having a molecular weight of less than 80 does not include an amide-based substance.

2. The method according to claim 1, wherein the water absorption of the carrier is 0.95-1.4mL/g, the pore volume in the carrier having a pore diameter of 2-8nm accounts for 15-30% of the total pore volume, and the pore volume in the carrier having a pore diameter of 2-6nm accounts for 5-10% of the total pore volume.

3. The process according to claim 1, wherein the hydrodesulphurization catalytically active metal component comprises elements of group VIB and VIII metals, the molar ratio of organic substances having a molecular weight of less than 80 to the elements of group VIII metals being between 0.2 and 5.

4. The method of claim 3, wherein the molar ratio of the organic substance having a molecular weight of less than 80 to the group VIII metal element is 0.5-3.

5. The method of any one of claims 1-3, wherein the organic substance having a molecular weight of less than 80 is one or more of methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, ethylene glycol, formic acid, acetic acid, propionic acid, ethylenediamine, ethanolamine, ethylamine, propylamine, butylamine, glycine.

6. The process according to claim 3 or 4, wherein the amounts of group VIB and group VIII metal elements are such that the content of group VIII metal elements, calculated as oxides and based on the dry weight of the resulting catalyst, is from 1 to 15% by weight; the content of the VIB group metal element is 5-60 wt%; the carrier is selected from one or more of alumina, silica, titania, zirconia, activated carbon and molecular sieve.

7. The process according to claim 6, wherein the amounts of group VIB metal element and group VIII metal element are such that the amount of group VIII metal element is from 3 to 10% by weight, calculated as oxide, based on the dry weight of the resulting catalyst; the content of the VIB group metal element is 10-45 wt%.

8. A process according to any one of claims 1 to 3, wherein the drying is carried out at 55-75 ℃ for 2-8 h.

9. The process of any one of claims 1 to 3, wherein the loading of the hydrodesulphurisation catalytically active metal component and the organic material each employs an impregnation process.

10. The process of claim 9, further comprising drying the organic material after loading the hydrodesulfurization catalytically active metal component and prior to loading the organic material, wherein the drying conditions prior to loading the organic material include a drying temperature of from 90 ℃ to 200 ℃ for a period of from 2 hours to 8 hours.

11. A hydrodesulphurisation catalyst made by the process of any of claims 1-10.

12. A process for the preparation of a sulphided hydrodesulphurisation catalyst comprising preparing a hydrodesulphurisation catalyst by a process as claimed in any of claims 1 to 10 and sulphiding the hydrodesulphurisation catalyst without drying and direct temperature programming.

13. The preparation method as claimed in claim 12, wherein the temperature-programmed rise rate is 5-60 ℃/hr, the vulcanization temperature is 280-420 ℃, the vulcanization pressure is 0.1-15MPa, and the volume space velocity is 0.5-20 hr^-1The volume ratio of hydrogen to oil is 100-: 1.