CN114437780B

CN114437780B - Residual oil hydrotreating method

Info

Publication number: CN114437780B
Application number: CN202011106737.3A
Authority: CN
Inventors: 袁胜华; 蒋淑娇
Original assignee: China Petroleum and Chemical Corp; Sinopec Dalian Research Institute of Petroleum and Petrochemicals
Current assignee: Sinopec Dalian Petrochemical Research Institute Co ltd; China Petroleum and Chemical Corp
Priority date: 2020-10-16
Filing date: 2020-10-16
Publication date: 2023-03-24
Anticipated expiration: 2040-10-16
Also published as: CN114437780A

Abstract

The invention discloses a residual oil hydrotreating method, which adopts a fixed bed hydrogenation process and comprises the following steps: in the presence of hydrogen, sequentially contacting a residual oil raw material with at least one hydrodesulfurization catalyst and at least one hydrodenitrogenation catalyst to carry out hydrogenation reaction to obtain hydrogenated oil; wherein the hydrodesulfurization catalyst comprises: the catalyst comprises a carrier, molybdenum element, a VIII group metal element and a niobium auxiliary agent, wherein the molybdenum element is at least partially present in the catalyst in the form of carbonyl molybdenum, and the VIII group metal is at least partially present in the catalyst in the form of a complex compound with polyhydric alcohol; the hydrodenitrogenation catalyst comprises: the catalyst comprises a carrier, molybdenum and a VIII group metal element, wherein the molybdenum element is at least partially present in the catalyst in the form of carbonyl molybdenum, and the VIII group metal is at least partially present in the catalyst in the form of a complex compound containing nitrogen and a lone pair electron compound. The residual oil hydrotreating method has the effects of deep desulfurization and denitrification and simultaneously has higher carbon residue removal effect.

Description

Residual oil hydrotreating method

Technical Field

The invention belongs to the field of petrochemical industry, and relates to a residual oil hydrotreating method.

Background

The fixed bed residual oil hydrotreating technology is the most effective residual oil pretreatment technology in the industry at present, reduces the contents of metal, sulfur, nitrogen and asphaltene in the raw materials by hydrogenation, improves the hydrogen-carbon ratio, and provides high-quality raw materials for devices such as catalytic cracking and the like. The fixed bed residual oil hydrotreatment usually adopts hydrogenation protective agent, hydrodemetallization catalyst, hydrodesulfurization catalyst and hydrodenitrogenation (residual carbon removal) catalyst for grading use, and the reactions of hydrodemetallization, hydrodesulfurization, hydrodenitrogenation, hydrodecarbon removal and the like are completed through the hydrogenation process. The basic principle of grading is that the particle size of the catalyst is from large to small along the direction of liquid phase material flow, the average pore diameter is from large to small, the porosity is from large to small, and the activity is from low to high.

The residual oil hydrotreating catalyst usually adopts inorganic refractory oxide as carrier and oxides of VIII and/or VIB metals as active metal components, and its preparation method is usually impregnation method, mixing method, etc. CN1394936A discloses a hydrorefining catalyst, which is prepared by an impregnation method by using a VIB group metal component and a VIII group metal component as active components and nickel-containing alumina as a carrier. CN1351115A discloses a preparation method of a hydrotreating catalyst, which is prepared by mixing, extruding, molding, drying and roasting two kinds of alumina with different properties and a solution containing VIB group metals and VIII group metals.

In recent years, researchers have been developing new hydrodesulfurization catalysts and hydrodenitrogenation catalysts.

CN110465305A discloses a preparation method of a supported hydrodesulfurization catalyst with acidity. The method comprises the following steps: loading a molecular sieve on the surface of a carbon-based material to obtain an acidic carbon-based carrier material; preparing a precursor solution of an active component of the hydrodesulfurization catalyst, impregnating an acidic carbon-based carrier material in the precursor solution, loading the active component on the surface of the acidic carbon-based carrier material, and then drying and calcining to obtain the acidic supported hydrodesulfurization catalyst. The catalyst realizes the removal of sulfide containing substituent groups by depending on the isomerization performance of the acidity of the catalyst, but the extra acidity increases the risk of carbon deposition and coke formation of the catalyst when heavy oil products are treated, and reduces the use stability of the catalyst.

CN107398282A discloses preparation and application of a non-supported hydrodesulfurization catalyst with a hydrotalcite-like layered structure. The catalyst takes W as an active component and Ni and Zr as auxiliary agents. Firstly, ni, al and Zr are introduced into hydrotalcite laminates by a coprecipitation method, tungsten is introduced into hydrotalcite layers by an ion exchange method, and then NiWAlZr catalyst with hydrotalcite special layered structure is prepared by roasting, so that high dispersion and weak interaction of active components are realized. The prepared catalyst shows higher hydrodesulfurization activity in the hydrodesulfurization reaction of oil products. The catalyst has high hydrodesulfurization activity, but due to high dispersion and weak interaction among metals, under the severe conditions of treating inferior heavy oil, the aggregation of active metals is easily caused, the utilization rate of the metals is reduced, and the stability of the catalyst is reduced.

CN104096584B discloses a preparation method of a transition metal phosphide catalyst which can be used for residual oil hydrodesulfurization and hydrodenitrogenation reactions. The method mixes alumina and activated carbon as a carrier, and the active component is Ni ₂ P、MoO ₃ Andor WO ₃ CoO and/or NiO. The preparation method of the catalyst improves the problem that nickel aluminate is easy to generate in the traditional high-temperature reduction process of metal ions to a certain extent, improves the activity of the catalyst to a certain extent, however, takes active carbon as part of the carrier,the total acid amount and mechanical strength of the carrier are reduced, the dispersion of the active metal is reduced, and further improvement of the desulfurization rate and the denitrification rate on the catalyst is hindered.

CN103627424B discloses a preparation method of residual oil hydrodenitrogenation catalyst. The carrier being Al ₂ O ₃ 、SiO ₂ Or any one of the active carbon, the active metal is Mo or W and Ni. Preparation of the catalyst: preparing terephthalic acid solution from terephthalic acid, nickel salt, urea and ammonium salt, impregnating the solution on the surface of a carrier by adopting an isometric impregnation method, crystallizing and drying to obtain nickel salt hydrotalcite microcrystal; and (3) immersing hydrotalcite microcrystal into a sodium salt solution of Mo or W, washing, drying and roasting the obtained green solid particles to obtain the residual oil hydrodenitrogenation catalyst. The method can highly disperse the metal active component on the surface of the inner hole of the carrier, thereby improving the activity of the catalyst, but the utilization rate of the active metal in the preparation process is limited.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a residual oil hydrotreating method. The residual oil hydrotreating method has the effects of deep desulfurization and denitrification and simultaneously has higher carbon residue removal effect.

The invention provides a residual oil hydrotreating method, which adopts a fixed bed hydrogenation process and comprises the following steps: in the presence of hydrogen, sequentially contacting a residual oil raw material with at least one hydrodesulfurization catalyst and at least one hydrodenitrogenation catalyst to carry out hydrogenation reaction to obtain hydrogenated oil;

wherein the hydrodesulfurization catalyst comprises: the catalyst comprises a carrier, molybdenum element, a VIII group metal element and an auxiliary agent niobium, wherein the molybdenum element is at least partially present in the catalyst in the form of carbonyl molybdenum, and the VIII group metal element is at least partially present in the catalyst in the form of a complex of the VIII group metal and polyhydric alcohol;

the hydrodenitrogenation catalyst comprises: the catalyst comprises a carrier, molybdenum and a VIII group metal element, wherein at least part of the molybdenum element exists in the catalyst in the form of carbonyl molybdenum, at least part of the VIII group metal element exists in the catalyst in the form of VIII group metal complex, and a complexing agent is a compound containing nitrogen and lone pair electrons.

In the hydrodesulfurization catalyst according to the invention, the content of group VIII metal, calculated as oxide, is from 0.5% to 8.0%, preferably from 1.0% to 6.0%, the content of molybdenum, calculated as oxide, is from 5.0% to 25.0%, preferably from 8.0% to 20.0%, and the content of niobium, calculated as niobium pentoxide, is from 0.5% to 6.0%, preferably from 1.0% to 4.0%, based on the weight of the support.

In the hydrodesulfurization catalyst according to the invention, the molybdenum element is present in the catalyst at least partly in the form of molybdenum carbonyls, the molybdenum present in the form of molybdenum carbonyls making up more than 40%, preferably from 50% to 90%, of the total molybdenum content, calculated as molybdenum atoms.

In the hydrodesulfurization catalyst, the form of the molybdenum element existing in the catalyst comprises carbonyl molybdenum and molybdenum oxide, wherein the ratio of the carbonyl molybdenum to the molybdenum oxide calculated by molybdenum atoms is 4:6-9.5:0.5, preferably 7:3-9:1.

in the hydrodesulfurization catalyst of the present invention, the group VIII metal is at least one selected from nickel and cobalt. The polyalcohol is one or more of erythritol, 1, 4-butanediol, glycerol, 1, 3-propylene glycol, polyethylene glycol (molecular weight below 2000) and diethylene glycol. The use amount of the polyol is 50-200%, preferably 70-150% of the theoretical complex amount of the VIII group metal.

In the hydrodesulfurization catalyst of the present invention, the carrier may be at least one of alumina, silica, molecular sieve, activated carbon, titanium aluminum, titanium silicon, etc., preferably alumina.

The properties of the hydrodesulfurization catalyst of the invention are as follows: the specific surface area is 50-300m ² A/g, preferably from 100 to 240m ² The pore volume is 0.4 to 1.2mL/g, preferably 0.5 to 1.0mL/g.

The hydrodesulfurization catalyst of the present invention is a shaped body which may be in the shape generally employed for fixed bed hydrodesulfurization catalysts, such as a strip, clover, tetrafoil, sphere, cylinder, etc., and has a particle size of 1.0 to 10.0mm, preferably 2.0 to 8.0 mm.

The invention also provides a preparation method of the hydrodesulfurization catalyst, which comprises the following steps:

(1) Preparing a first molybdenum carbonyl-containing catalyst intermediate;

(2) Loading niobium on the catalyst intermediate obtained in the step (1), and drying to obtain a catalyst intermediate containing niobium and molybdenum carbonyl;

(3) And (3) impregnating the catalyst intermediate containing niobium and molybdenum carbonyl obtained in the step (2) with an impregnating solution containing VIII group metal and polyhydric alcohol, and drying to obtain the hydrodesulfurization catalyst.

In the step (1), the first catalyst intermediate containing molybdenum carbonyl can be prepared by first preparing MoO loaded on a first carrier ₃ Then MoO is further reacted with ₃ At least partially converted to molybdenum carbonyls to produce a first catalyst intermediate comprising molybdenum carbonyls.

The preparation of the first carrier loaded with MoO ₃ The catalyst intermediate can be prepared by conventional methods such as a coprecipitation method, an impregnation method, a kneading method and the like, and is preferably prepared by the impregnation method, and the preparation process comprises the following steps: dipping a first molybdenum-containing solution on a first carrier, drying and roasting to obtain the MoO loaded on the first carrier ₃ The catalyst intermediate of (1). The first carrier can be a commercially available carrier or a carrier prepared according to the methods disclosed in the prior art, and is suitable for residual oil hydrodesulfurization catalysts. The solute in the first molybdenum-containing solution comprises at least one of ammonium molybdate, heteropolyacid salts of molybdenum, and the like. The impregnation method may be an equal volume impregnation, or may be a supersaturation impregnation, and an equal volume impregnation is preferred. The drying conditions were as follows: the drying temperature is 80-180 ℃, and the drying time is 2-6h; the roasting conditions are as follows: the roasting temperature is 400-600 ℃, and the roasting time is 2-5h. The first carrier is loaded with MoO ₃ The catalyst intermediate is a molded body which can be molded by a conventional method, such as extrusion molding, and the like, and conventional molding aids, such as peptizing agents, extrusion aids, and the like, can be added in the molding process.

The first catalyst intermediate containing the molybdenum carbonyl is prepared by the following steps: moO loaded on first carrier ₃ The catalyst intermediate is mixed with an organic solvent I, a first catalyst and ether gas to perform a first reaction, and then carbon monoxide is introduced into a reaction system to perform the reactionAnd (3) carrying out a second reaction, and drying to obtain a first catalyst intermediate containing molybdenum carbonyl. The organic solvent I can be at least one of carbon tetrachloride, trichloropropane, trichloromethane, perchloroethylene and trichloroethylene. The first catalyst can be at least one of iron pentacarbonyl, nickel tetracarbonyl and cobaltic octacarbonyl. Organic solvent I and first loaded MoO ₃ The mass ratio of the catalyst intermediate (2) is 1:1-5:1, preferably 2:1-4:1. first catalyst and first supported MoO ₃ The mass ratio of the catalyst intermediate (2) is 1:10-1:50, preferably 1:20-1:40. the reaction conditions of the first reaction are as follows: the reaction pressure is 1.0-10.0MPa, preferably 3.0-6.0MPa, the reaction temperature is 150-300 ℃, preferably 180-250 ℃, and the reaction time is 1.0-10.0 h, preferably 3.0-6.0 h. The ether gas can be one or a mixture of diethyl ether and dimethyl ether. The ether gas is introduced in an amount to maintain the pressure required for the first reaction. The reaction conditions of the second reaction are as follows: the reaction pressure is 5.0-20.0MPa, preferably 8.0-14.0MPa, the reaction temperature is 50-150 ℃, preferably 70-120 ℃, and the reaction time is 1.0-10.0 h, preferably 3.0-6.0 h. Wherein the carbon monoxide partial pressure accounts for more than 50 percent of the reaction pressure, and preferably 60 to 80 percent. The drying conditions were as follows: the drying temperature is 90-150 ℃, and the drying time is 1-4 h.

In the step (2), the method for loading niobium on the catalyst intermediate obtained in the step (1) may be an impregnation method, and the impregnation method may be a saturated impregnation method, an unsaturated impregnation method, or the like. The impregnation solution may be prepared using a soluble niobium-containing compound. The drying is as follows: the drying temperature is 90-150 ℃, and the drying time is 1-4 h. The soluble niobium-containing compound comprises at least one of ammonium niobium oxalate, sodium niobium oxalate, potassium niobium oxalate and the like, and ammonium niobium oxalate is preferred.

In the step (3), the preparation method of the impregnation liquid containing the VIII group metal and the polyhydric alcohol comprises the following steps: dissolving VIII metal compound and polyalcohol in water. The group VIII metal compound is derived from soluble salts, such as at least one of nitrate, citrate, monohydrogen phosphate, dihydrogen phosphate, and the like. In the impregnating solution, the concentration of the VIII group metal is 0.1-1.0 mol/L, and the concentration of the polyalcohol is 20.0-200.0 g/L. The impregnation may be carried out by an isovolumetric impregnation method, an unsaturated impregnation method, or the like. The drying conditions were: the complex of the group VIII metal and the polyol is carried out without decomposition, and specifically, the complex may be: the temperature is 90-150 ℃ and the time is 1-4 h. The polyalcohol is one or more of 1, 4-butanediol, 1, 3-propylene glycol, erythritol, glycerol, polyethylene glycol (molecular weight below 2000) and diethylene glycol.

In the hydrodenitrogenation catalyst, the content of the VIII group metal calculated by oxide is 0.5-8.0%, preferably 1.0-6.0%, and the content of molybdenum calculated by oxide is 5.0-32.0%, preferably 8.0-25.0%, based on the weight of the carrier.

In the hydrodenitrogenation catalyst of the present invention, the molybdenum element is at least partially present in the catalyst in the form of molybdenum carbonyl, and the molybdenum present in the form of molybdenum carbonyl represents more than 40%, preferably 50% to 90%, of the total molybdenum, calculated as molybdenum atoms.

In the hydrodenitrogenation catalyst, the form of the molybdenum element existing in the catalyst comprises carbonyl molybdenum and molybdenum oxide, wherein the ratio of the carbonyl molybdenum to the molybdenum oxide calculated by molybdenum atoms is 4:6-9.5:0.5, preferably 7:3-9:1.

in the hydrodenitrogenation catalyst of the present invention, the group VIII metal is at least one selected from nickel and cobalt. The complexing agent is a compound containing nitrogen element and lone pair electrons, and comprises at least one of ammonia water, urea, glycine, triethanolamine, ethylenediamine tetraacetic acid, nitrilotriacetic acid, N-methylacetamide, N-methylformamide and the like. The content of the complexing agent is 50-200%, preferably 70-150% of the theoretical complexing amount of the VIII group metal.

In the hydrodenitrogenation catalyst of the present invention, the carrier may be at least one of alumina, silica, molecular sieves, activated carbon, titanium aluminum, titanium silicon, and the like, and preferably alumina.

The hydrodenitrogenation catalyst of the invention has the following properties: the specific surface area is 120-300m ² Per g, preferably from 150 to 250m ² The pore volume is 0.3-1.2mL/g, preferably 0.4-0.8mL/g, the total acid content is 0.3-1.2mmol/g, preferably 0.5-1.0 mmol/g, and the strong acid content is 5% of the total acid content-40%, preferably 10% to 25%, of medium strong acid content ranging from 5% to 40%, preferably 15% to 30%, of the total acid content.

The hydrodenitrogenation catalyst of the present invention is a molded article, and the shape thereof may be a shape generally used for a fixed bed hydrogenation catalyst, such as a strip, clover, sphere, cylinder, etc., and the particle size thereof is 1.0 to 8.0 mm, preferably 1.5 to 8.0 mm.

The invention also provides a preparation method of the hydrodenitrogenation catalyst, which comprises the following steps:

(I) Preparing a second molybdenum carbonyl-containing catalyst intermediate;

(II) impregnating the second catalyst intermediate containing the carbonyl molybdenum obtained in the step (I) with an impregnating solution containing VIII group metal and a complexing agent, and drying to obtain the hydrodenitrogenation catalyst.

In step (I), the preparation of the second molybdenum carbonyl-containing catalyst intermediate may be preceded by the preparation of a second MoO-supported carrier ₃ Then MoO ₃ At least partially converted to molybdenum carbonyls to produce a second molybdenum carbonyl-containing catalyst intermediate.

The preparation of the second carrier loaded with MoO ₃ The catalyst intermediate can be prepared by conventional methods such as a coprecipitation method, an impregnation method, a kneading method and the like, and is preferably prepared by the impregnation method, and the preparation process comprises the following steps: dipping the solution containing molybdenum on the second carrier, drying and roasting to obtain the second carrier loaded MoO ₃ The catalyst intermediate of (1). The second carrier can be a commercially available carrier or a carrier prepared according to the methods disclosed in the prior art, and is suitable for residual oil hydrodenitrogenation catalysts. The solute in the second molybdenum-containing solution includes at least one of ammonium molybdate, a heteropolyacid salt of molybdenum, and the like. The impregnation method may be an equal volume impregnation, or may be a supersaturation impregnation, and an equal volume impregnation is preferred. The drying conditions were as follows: the drying temperature is 80-180 ℃, and the drying time is 2-6h; the roasting conditions are as follows: the roasting temperature is 400-600 ℃, and the roasting time is 2-5h. The second carrier is loaded with MoO ₃ The catalyst intermediate is a molded body, and can be molded by a conventional method, such as extrusion molding, and the like, and during the molding, the molded body can be formedConventional forming aids such as peptizers, extrusion aids, etc. are added.

The second catalyst intermediate containing molybdenum carbonyl is prepared by the following steps: moO loaded on second carrier ₃ The catalyst intermediate is mixed with an organic solvent I, a first catalyst and ether gas to generate a first reaction, then carbon monoxide is introduced into a reaction system to generate a second reaction, and the second reaction is dried to prepare a second catalyst intermediate containing molybdenum carbonyl. The organic solvent I can be at least one of carbon tetrachloride, trichloropropane, trichloromethane, perchloroethylene and trichloroethylene. The first catalyst can be at least one of iron pentacarbonyl, nickel tetracarbonyl and cobaltic octacarbonyl. Organic solvent I and second loaded MoO ₃ The mass ratio of the catalyst intermediate (2) is 1:1-5:1, preferably 2:1-4:1. first catalyst and second supported MoO ₃ The mass ratio of the catalyst intermediate (2) is 1:10-1:50, preferably 1:20-1:40. the reaction conditions of the first reaction are as follows: the reaction pressure is 1.0-10.0MPa, preferably 3.0-6.0MPa, the reaction temperature is 150-300 ℃, preferably 180-250 ℃, and the reaction time is 1.0-10.0 h, preferably 3.0-6.0 h. The ether gas can be one or a mixture of diethyl ether and dimethyl ether. The ether gas is introduced in an amount to maintain the pressure required for the first reaction. The reaction conditions of the second reaction are as follows: the reaction pressure is 5.0-20.0MPa, preferably 8.0-14.0MPa, the reaction temperature is 50-150 ℃, preferably 70-120 ℃, and the reaction time is 1.0-10.0 h, preferably 3.0-6.0 h. Wherein the carbon monoxide partial pressure accounts for more than 50 percent of the reaction pressure, and preferably 60 to 80 percent. The drying conditions were as follows: the drying temperature is 90-150 ℃, and the drying time is 1-4 h.

In the step (II), the preparation method of the impregnating solution containing the VIII group metal and the complexing agent comprises the following steps: dissolving VIII group metal compound and complexing agent in water. The group VIII metal compound is derived from soluble salts, such as at least one of nitrate, citrate, monohydrogen phosphate, dihydrogen phosphate, and the like. In the impregnating solution, the concentration of the VIII group metal is 0.1-1.0 mol/L, and the concentration of the complexing agent is 20.0-200.0 g/L. The impregnation may be carried out by an isovolumetric impregnation method, an unsaturated impregnation method, or the like. The drying conditions were: the reaction is carried out under the condition that the VIII group metal and the complex compound are not decomposed, and the VIII group metal and the complex compound can be specifically: the temperature is 90-150 ℃ and the time is 1-4 h. The complexing agent is at least one of ammonia water, urea, glycine, triethanolamine, ethylenediamine tetraacetic acid, nitrilotriacetic acid, N-methylacetamide, N-methylformamide and the like.

In the invention, the hydrodesulfurization catalyst and the hydrodenitrogenation catalyst can be graded and filled in various ways, and the grading principle can adopt the conventional grading principle, such as that the particle size is gradually reduced, the average pore size is gradually reduced and the activity is gradually increased along the liquid phase material flow direction.

In the residual oil hydrotreating method, the loading volume of the hydrodesulfurization catalyst accounts for 20-50% of the total catalyst loading volume, and the loading volume of the hydrodenitrogenation catalyst accounts for 30-60% of the total catalyst loading volume.

In order to prolong the service life of the hydrodesulfurization catalyst, a hydrogenation protective agent and a hydrodemetallization catalyst are filled in front of the hydrodesulfurization catalyst. The hydrogenation protective agent and the hydrogenation demetalization catalyst can adopt catalysts commonly used in the field, generally adopt an alumina-based carrier, and take VIB group and/or VIII group metals as active metal components. The hydrogenation protective agent comprises 2.0-8.0% of VIB group metal oxide and 1.0-3.0% of VIII group metal oxide based on the weight of the catalyst. The hydrodemetallization catalyst comprises, by weight, 5.0-14.0% of VIB group metal oxide and 2.0-5.0% of VIII group metal oxide. The hydrogenation protective agent and the hydrogenation demetalization catalyst can be obtained by commercial products, such as FZC series catalysts developed and produced by China petrochemical smoothing petrochemical research institute.

In the residual oil hydrotreating method, the filling volume of the hydrodesulfurization catalyst and the hydrodenitrogenation catalyst accounts for more than 60% of the total catalyst filling volume, and can be 60-90%.

Before the hydrodesulfurization catalyst and the hydrodenitrogenation catalyst are used, the hydrodesulfurization catalyst and the hydrodenitrogenation catalyst need to be vulcanized, and conventional in-situ presulfurization or ex-situ presulfurization can be adopted.

The following vulcanization process is preferred in the present invention: the hydrodesulfurization catalyst or the hydrodenitrogenation catalyst is contacted with a vulcanizing liquid and hydrogen to carry out vulcanization, and the vulcanization process is divided into two stages, namely a first stage: heating to 160-180 ℃, keeping the temperature for 2-6 hours, and in the second stage: heating to 250-320 ℃, and keeping the temperature for 2-6 hours.

In the vulcanization method, the temperature rise rate in the first stage is 0.5-2.0 ℃ per minute, and the temperature rise rate in the second stage is 1.0-3.0 ℃ per minute.

In the vulcanization method, the vulcanization liquid comprises a solvent and a sulfur-containing solute. The mass content of the sulfur-containing solute in the vulcanizing liquid is 1.0-10.0%, preferably 2.0-8.0%. The solvent is liquid hydrocarbon. Wherein the liquid hydrocarbon is hydrocarbon with final distillation point not higher than 300 deg.C, and is selected from one or more of saturated alkane with carbon number of 6-10, cycloalkane with carbon number of 6-10, and distillate. The distillate is preferably low-nitrogen distillate with nitrogen content not higher than 20 mu g/g. The sulfur-containing solute has a solubility of 10wt% or more in the solvent at normal temperature and is decomposed by reaction with hydrogen gas at high temperature to generate H ₂ S containing sulfur compounds, e.g. CS ₂ At least one of dimethyl disulfide, dimethyl sulfoxide, tetramethyl sulfoxide, dodecyl sulfide, etc. The dosage of the sulfuration solution is 0.5-6.0 g/h, preferably 1.0-5.0 g/h per gram of the catalyst. The hydrogen has a purity of not less than 90 v%. The vulcanization conditions were as follows: the hydrogen pressure is 1.0-20.0MPa, preferably 2.0-16.0MPa, and the hydrogen flow is 3-20 mL/min, preferably 5-15 mL/min per gram of catalyst.

The resid feedstock of the present invention can comprise an atmospheric resid and/or a vacuum resid. The residual oil raw material can also contain one or more of coker gas oil, deasphalted oil and heavy distillate oil. In the residual oil raw material, the sulfur content is not higher than 6.0 percent and can be 10 to 5.0 percent by mass; the content of the Kangshi carbon residue is not higher than 25 percent and can be 10 to 20 percent; the total content of heavy metal nickel and vanadium is not higher than 160 mu g/g, and can be 20-120 mu g/g; the total nitrogen content is not higher than 0.90%, and may be 0.20% to 0.70%.

In the present invention, the fixed bed hydrotreating operation conditions are as follows: reaction temperature of 320-400 ℃ and reactionThe reaction pressure is 6.0-25.0 MPa, the volume ratio of hydrogen to oil is 200 ^-1 。

The hydrogenated oil obtained by the residual oil hydrotreating method is used as the feed of a catalytic cracking device to produce gasoline, diesel oil, fuel oil and the like, or is used as the feed of the hydrocracking device to produce high-cetane-number diesel oil or chemical raw materials.

Compared with the prior art, the invention has the following advantages:

1. the residual oil fixed bed hydrotreating method of the invention adopts the hydrodesulfurization catalyst and the hydrodenitrogenation catalyst for grading filling, has ultra-deep desulfurization and denitrification activity, simultaneously has higher carbon residue removal activity and has good catalyst stability.

2. In the hydrodesulfurization catalyst, active components mainly exist in the catalyst in the form of carbonyl molybdenum, group VIII metal and polyol complex, and form a uniformly dispersed active phase with high sulfidation degree under the action of an auxiliary agent niobium, and after a Ni (Co) -Mo-S active phase edge replaces a Mo atom, the niobium can strengthen the dissociation and activation of an S = S atom on the active phase to hydrogen, promote the transfer of dissociated active hydrogen to sulfide, strengthen the activity of a hydrogenation saturation desulfurization path of the catalyst, and is particularly suitable for deep hydrogenation removal of heavy sulfides of heavy oils with high aromatic content and large steric hindrance.

3. In the hydrodenitrogenation catalyst, the active component mainly exists in the catalyst in the form of carbonyl molybdenum, VIII group metal and a specific nitrogen-containing complex, so that the existing state of the active component on a carrier is improved, the action of the active component and the carrier is improved, the hydrodenitrogenation catalyst is favorable for generating a Ni (Co) -Mo-S active phase with high denitrification activity and a suitable acid center after being vulcanized at low temperature, and the hydrogenation center and the acid center have good matching action, have deep hydrodenitrogenation activity and simultaneously have good desulfurization and residual carbon removal performances.

Detailed Description

The present invention will be further described with reference to the following examples.

In the invention, XPS is measured on a MultiLab 2000 type X-ray photoelectron spectrometer under the following operating conditions: light source: al K α, eb = 1.6 eV, the position of the peak of the Al 2p spectrum (C1 s, 285.0 eV) of the reference catalyst support corrects for charge-induced spectral peak shifts.

In the invention, the specific surface area and the pore volume are measured by adopting an ASAP2405 physical adsorption instrument, and the measuring method comprises the following steps: after the sample is processed, liquid N ₂ Used as adsorbate, the adsorption temperature is-196 ℃, and analysis and test are carried out. The specific surface area is calculated by the BET method, and the pore volume and pore distribution are calculated by the BJH method.

Example 1

Weighing 1000.0g of alumina dry glue powder, adding 20.0g of citric acid and 15.0g of sesbania powder, uniformly mixing, adding 800.0g of aqueous solution containing 2.0 percent of nitric acid by mass, rolling for 15.0min, and extruding strips by using a clover orifice plate with the diameter of 3.5 mm. Drying at 120 ℃ for 4.0h, and roasting at 780 ℃ for 4.0 h. The calcined support was designated S-1.

49.0g of ammonium heptamolybdate and 30.0g of 25wt% ammonia water are weighed and prepared into 180mL of aqueous solution, and the solution is recorded as MQ-1. Soaking 200g of S-1 in 180mL of MQ-1, drying at 160 ℃ for 4.0h, and roasting at 500 ℃ for 4.0h to obtain a carrier loaded MoO ₃ The catalyst intermediate of (1), designated MA-1.

60g of MA-1, 150g of carbon tetrachloride and 1.0g of iron pentacarbonyl are weighed and added into an autoclave with the volume of 500mL, ether gas is introduced, the pressure is maintained at 4.0MPa, the temperature is maintained at 200 ℃, and the reaction is carried out for 5 hours. Then, the temperature is reduced to 90 ℃, carbon monoxide is introduced, the pressure is increased to 12.0MPa, the reaction is carried out for 5 hours, the catalyst is taken out and dried for 2 hours at 120 ℃, and the catalyst intermediate containing the carbonyl molybdenum is obtained and is recorded as MT-1.

5.5 g of ammonium niobium oxalate was weighed and dissolved in 60.0mL of water to give a solution designated NQ-1, MT-1 was impregnated with NQ-1 and dried at 120 ℃ for 3.0 h to give a molybdenum carbonyl-containing catalyst intermediate designated MNT-1.

10.0g of nickel nitrate hexahydrate and 3.0g of 1, 3-propanediol were weighed out and dissolved in 55.0mL of water to obtain a solution designated as VQ-1, MNT-1 was impregnated with the solution designated as VQ-1, and the resulting solution was dried at 120 ℃ for 4.0 hours to obtain a catalyst designated as OC-1.

10.0g of OC-1 is taken and filled into a tubular reactor for presulfurization of the catalyst, and the vulcanizing liquid is CS with the mass fraction of 4.0 percent ₂ The flow of the introduced vulcanizing liquid is 30.0mL/h, the pressure of hydrogen is 3.0MPa, the flow rate of the hydrogen is 120mL/min, the reaction is divided into two temperature sections, the first stage starts from 120 ℃, the temperature rising rate is 1.0 ℃ per min, and the temperature is kept for 6.0h after the temperature reaches 160 ℃; in the second stage, the temperature is increased from 160 ℃ at the rate of 2.0 ℃ per min, the temperature is kept constant for 2.0h after the temperature is increased to 280 ℃, and the vulcanization is finished. The catalyst obtained after sulfidation was designated SC-1.

Example 2

Carrier S-1, carrier Supported MoO ₃ The procedure for preparing catalyst intermediate MA-1 of (1) was the same as in example 1.

60g of MA-1, 150g of carbon tetrachloride and 1.0g of nickel pentacarbonyl are weighed, added into an autoclave with the volume of 500mL, methyl ether gas is introduced, the pressure is maintained at 4.0MPa, the temperature is maintained at 200 ℃, and the reaction is carried out for 5 hours. Then, the temperature is reduced to 90 ℃, carbon monoxide is introduced, the pressure is increased to 12.0MPa, the reaction is carried out for 5 hours, the catalyst is taken out and dried for 2 hours at 120 ℃, and the catalyst intermediate containing the carbonyl molybdenum is obtained and is recorded as MT-2.

8.3 g of ammonium niobium oxalate was weighed and dissolved in 60.0mL of water to give a solution designated as NQ-2, MT-2 was impregnated with NQ-2 and dried at 120 ℃ for 3.0 h to give a molybdenum carbonyl-containing catalyst intermediate designated as MNT-2.

7.5 g of nickel nitrate hexahydrate and 2.7g of glycerol were weighed out and dissolved in 55.0mL of water to obtain a solution which was designated as VQ-2, MNT-2 was impregnated with the solution of VQ-2, and the obtained catalyst was designated as OC-2 after drying at 120 ℃ for 4.0 hours.

10.0g of OC-2 is taken and put into a tubular reactor for presulfurization of the catalyst, and the vulcanizing liquid is CS with the mass fraction of 4.0 percent ₂ The flow of the introduced vulcanizing liquid is 30.0mL/h, the pressure of hydrogen is 3.0MPa, the flow rate of the hydrogen is 120mL/min, the reaction is divided into two temperature sections, the first stage starts from 120 ℃, the temperature rising rate is 1.0 ℃ per min, and the temperature is kept for 6.0h after the temperature reaches 160 ℃; the second stage starts at 160C and,the heating rate is 2.0 ℃ per min, the temperature is kept constant for 2.0h after the temperature is increased to 280 ℃, and the vulcanization is finished. The catalyst obtained after sulfidation was designated as SC-2.

Example 3

Carrier S-1, carrier Supported MoO ₃ The catalyst intermediate MA-1 and the catalyst intermediate MT-1 containing molybdenum carbonyl and the intermediate MNT-1 containing niobium of (2) were prepared in the same manner as in example 1.

10.0g of cobalt nitrate hexahydrate and 15.8 g of polyethylene glycol with the molecular weight of 400 are weighed and dissolved in 55.0mL of water to obtain a solution which is marked as VQ-3, MNT-1 is soaked in the VQ-3 and is dried at 120 ℃ for 4.0h, and the obtained catalyst is marked as OC-3.

10.0g of OC-3 is taken and put into a tubular reactor for presulfurization of the catalyst, and the vulcanizing liquid is CS with the mass fraction of 4.0 percent ₂ The flow of the introduced vulcanizing liquid is 30.0mL/h, the pressure of hydrogen is 3.0MPa, the flow rate of the hydrogen is 120mL/min, the reaction is divided into two temperature sections, the temperature rise rate is 1.0 ℃ per min at the first stage from 120 ℃, and the temperature is kept for 6.0h after the temperature reaches 160 ℃; in the second stage, the temperature is increased from 160 ℃ at the rate of 2.0 ℃ per min, the temperature is kept constant for 2.0h after the temperature is increased to 280 ℃, and the vulcanization is finished. The catalyst obtained after sulfidation was noted as SC-3.

Example 4

Carrier S-1, carrier Supported MoO ₃ The procedure for preparing catalyst intermediate MA-1 of (1) was the same as in example 1. The procedure for the preparation of the molybdenum carbonyl-containing catalyst intermediate MT-2 and the niobium-containing intermediate MNT-2 was the same as in example 2.

Weighing 7.5 g of cobalt nitrate hexahydrate and 4.2 g of diethylene glycol with molecular weight, dissolving the cobalt nitrate hexahydrate and the diethylene glycol in 55.0mL of water to obtain a solution, marking as VQ-4, soaking MNT-2 in the VQ-4, and drying at 120 ℃ for 4.0 hours to obtain a catalyst, marking as OC-4.

10.0g of OC-4 is taken and put into a tubular reactor for presulfurization of the catalyst, and the vulcanizing liquid is CS with the mass fraction of 4.0 percent ₂ The flow of the introduced vulcanizing liquid is 30.0mL/h, the pressure of hydrogen is 3.0MPa, the flow rate of the hydrogen is 120mL/min, the reaction is divided into two temperature sections, the first stage starts from 120 ℃, the temperature rising rate is 1.0 ℃ per min, and the temperature is kept for 6.0h after the temperature reaches 160 ℃; the second stage starts from 160 ℃, and the temperature is increasedThe speed is 2.0 ℃ per min, the temperature is raised to 280 ℃ and then is kept constant for 2.0h, and the vulcanization is finished. The catalyst obtained after sulfidation was noted as SC-4.

Example 5

Weighing 2000.0g of alumina dry glue powder, adding 40.0g of citric acid and 50.0g of sesbania powder, uniformly mixing, adding 1800.0g of aqueous solution containing 4.0% of acetic acid by mass fraction, rolling for 15.0min, and extruding strips by using a clover orifice plate with the diameter of 2.5 mm. Drying at 130 ℃ for 6.0h, and roasting at 680 ℃ for 3.0 h. The calcined support was designated S-2.

68.0g of ammonium heptamolybdate and 30.0g of 25wt% ammonia water are weighed and prepared into 180mL of aqueous solution, and the solution is recorded as MQ-2. Soaking 200g S-2 in 180mL MQ-2, drying at 140 deg.C for 4.0h, and calcining at 480 deg.C for 2.0h to obtain a product containing MoO ₃ The catalyst intermediate of (1), designated MA-2.

50g of MA-2, 200g of carbon tetrachloride and 2.0g of nickel tetracarbonyl are weighed and added into an autoclave with the volume of 500mL, ether gas is introduced, the pressure is maintained at 4.0MPa, the temperature is maintained at 200 ℃, and the reaction is carried out for 5 hours. Then the temperature is reduced to 90 ℃, carbon monoxide is introduced, the pressure is increased to 12.0MPa, the reaction is carried out for 5h, the catalyst is taken out, and the material obtained is marked as MT-3 after being dried for 2.0h at 120 ℃.

8.2 g of nickel nitrate hexahydrate and 2.0g of urea are weighed and dissolved in 50.0mL of water to obtain a solution which is marked as BQ-1, MT-3 is soaked in the BQ-1, and the obtained catalyst is marked as NC-1 after being dried for 4.0 hours at 120 ℃.

10.0g of NC-1 is taken and put into a tubular reactor for presulfurization of the catalyst, and the sulfur solution is CS with the mass fraction of 5.0 percent ₂ The flow of the introduced vulcanizing liquid is 25.0 mL/h, the pressure of hydrogen is 6.0MPa, the flow rate of the hydrogen is 120mL/min, the reaction is divided into two temperature sections, the first stage starts from 80 ℃, the heating rate is 2.0 ℃ per min, and the temperature is kept for 4.0h after the temperature reaches 160 ℃; in the second stage, the temperature is increased from 160 ℃ at the rate of 2.0 ℃ per min to 300 ℃ and then is kept constant for 2.0h, and the vulcanization is finished. The catalyst obtained after sulfidation was designated as SN-1.

Example 6

The procedure for the preparation of MA-2 as support S-2, a catalyst intermediate containing molybdenum, was the same as in example 5.

50.0g of MA-2, 150g of carbon tetrachloride and 2.0g of cobaltosic octacarbonyl are weighed, added into an autoclave with the volume of 500mL, and ether gas is introduced, the pressure is maintained at 4.0MPa, the temperature is maintained at 200 ℃, and the reaction is carried out for 5 hours. Then, the temperature is reduced to 90 ℃, carbon monoxide is introduced, the pressure is increased to 12.0MPa, the reaction is carried out for 5 hours, the catalyst is taken out, and the catalyst is dried for 2 hours at 120 ℃, so that the obtained material is marked as MT-4.

Weighing 8.2 g of cobalt nitrate hexahydrate and 10.0g of EDTA, dissolving the mixture in 50.0mL of aqueous solution to obtain a solution, marking as BQ-2, impregnating MT-4 with the BQ-2, and drying at 120 ℃ for 4.0 hours to obtain a catalyst, marking as NC-2.

10.0g of NC-2 is taken and put into a tubular reactor for presulfurization of the catalyst, and the sulfur solution is CS with the mass fraction of 5.0 percent ₂ The flow of the introduced vulcanizing liquid is 25.0 mL/h, the pressure of hydrogen is 6.0MPa, the flow rate of the hydrogen is 120mL/min, the reaction is divided into two temperature sections, the first stage starts from 80 ℃, the temperature rise rate is 2.0 ℃ per min, and the temperature is kept for 4.0h after the temperature reaches 160 ℃; in the second stage, the temperature is increased from 160 ℃ at the rate of 2.0 ℃ per min to 300 ℃ and then is kept constant for 2.0h, and the vulcanization is finished. The catalyst obtained after sulfidation was noted as NC-2.

Example 7

The preparation of MA-2 as support S-2, a catalyst intermediate containing molybdenum, was carried out in the same manner as in example 5.

50.0g of MA-2, 150g of carbon tetrachloride and 2.0g of nickel tetracarbonyl are weighed, added into an autoclave with the volume of 500mL, methyl ether gas is introduced, the pressure is maintained at 4.0MPa, the temperature is maintained at 200 ℃, and the reaction is carried out for 5 hours. Then, the temperature is reduced to 90 ℃, carbon monoxide is introduced, the pressure is increased to 12.0MPa, the reaction is carried out for 5 hours, the catalyst is taken out, and the catalyst is dried for 2 hours at 120 ℃, so that the obtained material is marked as MT-5.

8.2 g of nickel nitrate hexahydrate and 2.0g of ethylenediamine are weighed and dissolved in 50.0mL of water to obtain a solution which is marked as BQ-3, MT-5 is soaked in the BQ-3, and the obtained catalyst is marked as NC-3 after being dried for 4.0 hours at 120 ℃.

10.0g of NC-3 is taken and put into a tubular reactor for presulfurization of the catalyst, and the vulcanizing liquid is CS with the mass fraction of 5.0 percent ₂ The flow of the introduced vulcanizing liquid is 25.0 mL/h, the pressure of the hydrogen is 6.0MPa, and the flow rate of the hydrogenThe reaction is divided into two temperature sections, the first stage starts from 80 ℃, the temperature rising rate is 2.0 ℃ per min, and the temperature is kept for 4.0 hours after the temperature reaches 160 ℃; in the second stage, the temperature is increased from 160 ℃ at the rate of 2.0 ℃ per min to 300 ℃ and then is kept constant for 2.0h, and the vulcanization is finished. The catalyst obtained after sulfidation was noted as SN-3.

Example 8

The preparation of MA-2 as the support S-2, a catalyst intermediate containing molybdenum, was carried out in the same manner as in example 1.

50.0g of MA-2, 150g of carbon tetrachloride and 2.0g of cobalt tetracarbonyl are weighed, added into an autoclave with the volume of 500mL, methyl ether gas is introduced, the pressure is maintained at 4.0MPa, the temperature is maintained at 200 ℃, and the reaction is carried out for 5 hours. Then, the temperature is reduced to 90 ℃, carbon monoxide is introduced, the pressure is increased to 12.0MPa, the reaction is carried out for 5 hours, the catalyst is taken out, and the catalyst is dried for 2 hours at 120 ℃, so that the obtained material is marked as MT-6.

8.2 g of cobalt nitrate hexahydrate and 2.5 g of N-methylacetamide were weighed out and dissolved in 50.0mL of water to obtain a solution designated as BQ-4, MT-6 was impregnated with BQ-4 and dried at 120 ℃ for 4.0 hours to obtain a catalyst designated as NC-4.

10.0g of NC-4 is taken and put into a tubular reactor for presulfurization of the catalyst, and the sulfur solution is CS with the mass fraction of 5.0 percent ₂ The flow of the introduced vulcanizing liquid is 25.0 mL/h, the pressure of hydrogen is 6.0MPa, the flow rate of the hydrogen is 120mL/min, the reaction is divided into two temperature sections, the first stage starts from 80 ℃, the heating rate is 2.0 ℃ per min, and the temperature is kept for 4.0h after the temperature reaches 160 ℃; in the second stage, the temperature is increased from 160 ℃ at the rate of 2.0 ℃ per min to 300 ℃ and then is kept constant for 2.0h, and the vulcanization is finished. The catalyst obtained after sulfidation was noted as SN-4.

Comparative example 1

Carrier S-1, carrier Supported MoO ₃ The catalyst intermediate MA-1 of (4) was prepared in the same manner as in example 1.

10.0g of nickel nitrate hexahydrate is weighed and dissolved in 60.0mL of water to obtain a solution which is marked as DQ-1, MA-1 is soaked by DQ-1, and the obtained catalyst is marked as DOC-1 after drying at 150 ℃.

10.0g of DOC-1 is taken and put into a tubular reactor for presulfurization of the catalyst, and the sulfur solution is CS with the mass fraction of 4.0 percent ₂ The flow of the introduced vulcanizing liquid is 30.0mL/h, the pressure of hydrogen is 3.0MPa, the flow rate of the hydrogen is 120mL/min, the reaction is divided into two temperature sections, the first stage starts from 120 ℃, the temperature rising rate is 1.0 ℃ per min, and the temperature is kept for 6.0h after the temperature reaches 160 ℃; in the second stage, the temperature is increased from 160 ℃ at the rate of 2.0 ℃ per min, the temperature is kept constant for 2.0h after the temperature is increased to 280 ℃, and the vulcanization is finished. The catalyst obtained after sulfiding was noted as DSC-1.

Comparative example 2

Support S-2, material MA-2, was prepared as in example 5.

8.2 g of nickel nitrate hexahydrate is weighed and dissolved in 50.0mL of water to obtain a solution which is marked as DQ-2, 50.0g of MA-2 is soaked in DQ-2, and the obtained catalyst is marked as DOC-2 after drying at 150 ℃.

10.0g of DOC-2 is taken and put into a tubular reactor for presulfurization of the catalyst, and the sulfur solution is CS with the mass fraction of 5.0 percent ₂ The flow of the introduced vulcanizing liquid is 25.0 mL/h, the pressure of hydrogen is 6.0MPa, the flow rate of the hydrogen is 120mL/min, the reaction is divided into two temperature sections, the first stage starts from 80 ℃, the heating rate is 2.0 ℃ per min, and the temperature is kept for 4.0h after the temperature reaches 160 ℃; in the second stage, the temperature is increased from 160 ℃ at the rate of 2.0 ℃ per min to 300 ℃ and then is kept constant for 2.0h, and the vulcanization is finished. The catalyst obtained after sulfiding was noted as DSC-2.

Comparative example 3

Carrier S-1, carrier Supported MoO ₃ The catalyst intermediate MA-1, the molybdenum carbonyl-containing support MT-1, and the solution VQ-1 of (4) were prepared in the same manner as in example 1.

MT-1 was impregnated with VQ-1 and dried at 120 ℃ for 4.0h to give the catalyst DOC-3.

10.0g of DOC-3 is taken and put into a tubular reactor for presulfurization of the catalyst, and the sulfur solution is CS with the mass fraction of 4.0 percent ₂ The flow of the introduced vulcanizing liquid is 30.0mL/h, the pressure of hydrogen is 3.0MPa, the flow rate of the hydrogen is 120mL/min, the reaction is divided into two temperature sections, the first stage starts from 120 ℃, the temperature rising rate is 1.0 ℃ per min, and the temperature is kept for 6.0h after the temperature reaches 160 ℃; the second stage starts from 160 ℃, the heating rate is 2.0 ℃ per min, the temperature is kept for 2.0h after the temperature is increased to 280 ℃, and the vulcanization is finished. The catalyst obtained after sulfurization was designated as DSC-3.

Comparative example 4

Support S-2, material MA-2, was prepared as in example 5.

8.2 g of nickel nitrate hexahydrate and 2.0g of urea were weighed and dissolved in 50.0mL of water to obtain a solution which was designated as DQ-3, 60.0 g of MA-2 was impregnated with DQ-3 and dried at 150 ℃ to obtain a catalyst which was designated as DOC-4.

10.0g of DOC-4 is taken and put into a tubular reactor for presulfurization of the catalyst, and the sulfur solution is CS with the mass fraction of 5.0 percent ₂ The flow of the introduced vulcanizing liquid is 25.0 mL/h, the pressure of hydrogen is 6.0MPa, the flow rate of the hydrogen is 120mL/min, the reaction is divided into two temperature sections, the first stage starts from 80 ℃, the heating rate is 2.0 ℃ per min, and the temperature is kept for 4.0h after the temperature reaches 160 ℃; in the second stage, the temperature is increased from 160 ℃ at the rate of 2.0 ℃ per min to 300 ℃ and then is kept constant for 2.0h, and the vulcanization is finished. The catalyst obtained after sulfiding was noted as DSC-4.

Comparative example 5

Carrier S-1, carrier Supported MoO ₃ The catalyst intermediate MA-1, the catalyst intermediate MT-1 containing molybdenum carbonyl, and the intermediate MNT-1 containing niobium were prepared in the same manner as in example 1, and the solution DQ-1 was prepared in the same manner as in comparative example 1.

MNT-1 is soaked by DQ-1 and dried for 4.0h at 120 ℃, and the obtained catalyst is marked as DOC-5.

10.0g of DOC-5 is taken and put into a tubular reactor for presulfurization of the catalyst, and the sulfur solution is CS with the mass fraction of 4.0 percent ₂ The flow of the introduced vulcanizing liquid is 30.0mL/h, the pressure of hydrogen is 3.0MPa, the flow rate of the hydrogen is 120mL/min, the reaction is divided into two temperature sections, the first stage starts from 120 ℃, the temperature rising rate is 1.0 ℃ per min, and the temperature is kept for 6.0h after the temperature reaches 160 ℃; in the second stage, the temperature is increased from 160 ℃ at the rate of 2.0 ℃ per min, the temperature is kept constant for 2.0h after the temperature is increased to 280 ℃, and the vulcanization is finished. The catalyst obtained after sulfiding was noted as DSC-5.

Comparative example 6

The preparation of the support S-2, the material MA-2 and the material MT-2 is the same as in example 5, and the preparation of the solution DQ-2 is the same as in comparative example 2.

MT-2 was impregnated with DQ-2 and dried at 120 ℃ for 4.0h to give the catalyst DOC-6.

10.0g of DOC-6 is taken and put into a tubular reactor for presulfurization of the catalyst, and the sulfur solution is CS with the mass fraction of 4.0 percent ₂ The flow of the introduced vulcanizing liquid is 30.0mL/h, the pressure of hydrogen is 3.0MPa, the flow rate of the hydrogen is 120mL/min, the reaction is divided into two temperature sections, the first stage starts from 120 ℃, the temperature rising rate is 1.0 ℃ per min, and the temperature is kept for 6.0h after the temperature reaches 160 ℃; in the second stage, the temperature is increased from 160 ℃ at the rate of 2.0 ℃ per min, the temperature is kept constant for 2.0h after the temperature is increased to 280 ℃, and the vulcanization is finished. The catalyst obtained after sulfiding was noted as DSC-6.

The above catalyst was calcined to 600 ℃ and the dry content was measured as shown in table 1.

TABLE 1 composition and Properties of catalysts obtained in examples and comparative examples

Catalyst numbering	Mo is MoO ₃ Calculated by weight percent	Nb with Nb ₂ O ₅ Calculated by weight percent	Calculated as oxide, ni (Co)% by weight	Specific surface area, m ² /g	Pore volume, mL/g
						OC-1	15.8	2.2	4.1	183	0.90
OC-2	15.9	2.9	3.0	184	0.88
						OC-3	15.9	2.1	3.9	185	0.88
OC-4	16.0	3.0	2.9	182	0.89
						CN-1	20.1	0	4.9	199	0.79
CN-2	20.3	0	5.0	198	0.77
						CN-3	20.2	0	5.1	194	0.78
CN-4	20.5	0	4.9	201	0.76
						DOC-1	16.0	0	4.1	183	0.89
DOC-2	20.0	0	4.8	204	0.77
						DOC-3	15.9	0	4.0	186	0.90
DOC-4	20.2	0	4.9	201	0.78
						DOC-5	15.6	2.1	4.0	181	0.86
DOC-6	20.5	0	5.1	198	0.75

The catalysts obtained in the above examples and comparative examples were characterized by XPS to obtain the ratio of molybdenum carbonyl to total molybdenum in terms of molybdenum atoms, and the results are shown in Table 2.

Table 2 XPS characterization results of catalysts obtained in each example and comparative example

Catalyst numbering	Molybdenum carbonyl in percent (based on molybdenum atom)
		OC-1	83
OC-2	82
		OC-3	85
OC-4	84
		CN-1	84
CN-2	81
		CN-3	85
CN-4	82
		DOC-1	0
DOC-2	0
		DOC-3	0
DOC-4	0
		DOC-5	83
DOC-6	85

Examples 9 to 12

To the embodiments1-8, the catalysts obtained were loaded in graded fashion, the properties of the residual feeds used being shown in table 3. Adopting a fixed bed process, filling a hydrogenation protective agent (FZC-100B) and a hydrogenation demetallization catalyst (FZC-204A) in front of a hydrogenation desulfurization catalyst, wherein the filling volume ratio of the protective agent to the hydrogenation demetallization catalyst to the hydrogenation desulfurization catalyst to the hydrogenation denitrification catalyst is 1.0:1.5:3:0:4.5. the operating conditions were: reaction temperature of 390 ℃, reaction pressure of 20.0MPa, hydrogen-oil volume ratio of 800:1, the liquid hourly space velocity is 0.2 h ^-1 . The evaluation results are shown in Table 4. The results of the evaluation for 1000 hours are shown in Table 4, and the results of the evaluation for 3000 hours are shown in Table 5.

Comparative examples 7 to 9

The activity of the catalysts obtained in comparative examples 1 to 6 was evaluated, and the properties of the residue feedstock are shown in Table 3. Adopting a fixed bed process, filling a hydrogenation protective agent (FZC-100B) and a hydrogenation demetallization catalyst (FZC-204A) in front of the catalyst, wherein the filling volume ratio of the protective agent to the hydrogenation demetallization catalyst to the hydrogenation desulfurization catalyst to the hydrogenation denitrification catalyst is 1.0:1.5:3.0:4.5. the operating conditions were: reaction temperature of 390 ℃, reaction pressure of 20.0MPa, hydrogen-oil volume ratio of 800:1, the liquid hourly space velocity is 0.2 h ^-1 . The results of the evaluation for 1000 hours are shown in Table 4, and the results of the evaluation for 3000 hours are shown in Table 5.

TABLE 3 Properties of the feed oils

Name of item	Residual oil feedstock
		Density (15 ℃), kg/m ³	997
Sulfur content, μ g/g	33607
		Nitrogen content,. Mu.g/g	4265
Saturated fraction, wt%	41.4
		The fragrance is in wt%	33.7
Gum, wt%	22.2
		Asphaltenes, wt.%	2.7
Carbon residue in wt%	18.0

TABLE 4 analysis of hydrogenation products for 1000h catalyst evaluation

	Desulfurization catalyst numbering	Denitrification catalyst numbering	Sulfur content, μ g/g	Nitrogen content,. Mu.g/g	Carbon residue in wt%
						Example 9	SC-1	SN-1	1469	652	4.5
Example 10	SC-2	SN-2	1104	758	5.7
						Example 11	SC-3	SN-3	1322	685	5.2
Example 12	SC-4	SN-4	1248	710	4.9
						Comparative example 7	DSC-1	DSC-2	5848	1856	8.8
Comparative example 8	DSC-3	DSC-4	4022	1577	8.1
						Comparative example 9	DSC-5	DSC-6	2547	1209	6.8

TABLE 5 catalyst hydrogenation evaluation 3000h product analysis results

	Desulfurization catalyst numbering	Denitrification catalyst numbering	Sulfur content, μ g/g	Nitrogen content,. Mu.g/g	Carbon residue in wt%
						Example 9	SC-1	SN-1	1856	717	4.7
Example 10	SC-2	SN-2	1352	790	6.0
						Example 11	SC-3	SN-3	1341	705	5.5
Example 12	SC-4	SN-4	1559	742	5.3
						Comparative example 7	DSC-1	DSC-2	7456	2204	11.0
Comparative example 8	DSC-3	DSC-4	5707	1859	9.8
						Comparative example 9	DSC-5	DSC-6	3995	1654	8.2

Claims

1. A residual oil hydrotreating method adopts a fixed bed hydrogenation process, and comprises the following steps: in the presence of hydrogen, sequentially contacting a residual oil raw material with at least one hydrodesulfurization catalyst and at least one hydrodenitrogenation catalyst to carry out hydrogenation reaction to obtain hydrogenated oil;

wherein the hydrodesulfurization catalyst comprises: the catalyst comprises a carrier, molybdenum element, a VIII group metal element and a niobium auxiliary agent, wherein the molybdenum element is at least partially present in the catalyst in the form of carbonyl molybdenum, and the VIII group metal element is at least partially present in the catalyst in the form of a complex of the VIII group metal and a polyalcohol;

the hydrodenitrogenation catalyst comprises: the catalyst comprises a carrier, molybdenum and a VIII group metal element, wherein at least part of the molybdenum element exists in the catalyst in the form of carbonyl molybdenum, at least part of the VIII group metal element exists in the catalyst in the form of VIII group metal complex, and a complexing agent is a compound containing nitrogen and lone pair electrons;

in the hydrodesulfurization catalyst, the weight of the carrier is taken as the reference, the content of VIII group metal calculated by oxide is 0.5-8.0%, the content of molybdenum calculated by oxide is 5.0-25.0%, and the content of niobium calculated by niobium pentoxide is 0.5-6.0%; the molybdenum element is at least partially present in the catalyst in the form of molybdenum carbonyl, and the molybdenum present in the form of molybdenum carbonyl accounts for more than 40% of the total molybdenum amount; the form of the molybdenum element existing in the catalyst comprises carbonyl molybdenum and molybdenum oxide, wherein the ratio of the carbonyl molybdenum to the molybdenum oxide calculated by molybdenum atoms is 4:6-9.5:0.5;

in the hydrodenitrogenation catalyst, on the basis of the weight of the carrier, the content of the VIII group metal calculated by oxide is 0.5-8.0%, and the content of molybdenum calculated by oxide is 5.0-32.0%; the molybdenum element is at least partially present in the catalyst in the form of molybdenum carbonyl, and the molybdenum present in the form of molybdenum carbonyl accounts for more than 40% of the total molybdenum amount; the form of molybdenum element existing in the catalyst comprises carbonyl molybdenum and molybdenum oxide, and the ratio of the carbonyl molybdenum to the molybdenum oxide calculated by molybdenum atoms is 4:6-9.5:0.5;

the hydrodesulfurization catalyst and the hydrodenitrogenation catalyst are graded and filled, and the grading principle is that along the direction of liquid-phase material flow, the particle size is gradually reduced, the average pore diameter is gradually reduced, the porosity is gradually reduced, and the activity is gradually increased;

the hydrodesulfurization catalyst accounts for 20-50% of the total catalyst filling volume, and the hydrodenitrogenation catalyst accounts for 30-60% of the total catalyst filling volume.

2. The method of claim 1, wherein: in the hydrodesulfurization catalyst, on the basis of the weight of the carrier, the content of the VIII group metal calculated by oxide is 1.0-6.0%, the content of molybdenum calculated by oxide is 8.0-20.0%, and the content of niobium calculated by niobium pentoxide is 1.0-4.0%.

3. A method according to claim 1 or 2, characterized in that: in the hydrodesulfurization catalyst, molybdenum element is at least partially present in the catalyst in the form of molybdenum carbonyl, and the molybdenum present in the form of molybdenum carbonyl accounts for 50-90% of the total molybdenum.

4. The method of claim 1, wherein: in the hydrodesulfurization catalyst, the form of molybdenum element existing in the catalyst comprises carbonyl molybdenum and molybdenum oxide, wherein the ratio of the carbonyl molybdenum to the molybdenum oxide in terms of molybdenum atoms is 7:3-9:1.

5. the method of claim 1, wherein: in the hydrodesulfurization catalyst, the VIII group metal is at least one of nickel and cobalt, and the polyalcohol is one or more of tetrol, 1, 4-butanediol, glycerol, 1, 3-propanediol, polyethylene glycol with molecular weight below 2000 and diethylene glycol.

6. The method of claim 1 or 5, wherein: in the hydrodesulfurization catalyst, the use amount of the polyol is 50-200% of the theoretical complex amount of the VIII group metal.

7. The method of claim 1 or 5, wherein: in the hydrodesulfurization catalyst, the use amount of the polyol is 70-150% of the theoretical complex amount of the VIII group metal.

8. The method of claim 1, wherein: in the hydrodesulfurization catalyst, the carrier is at least one of alumina, silica, molecular sieve, activated carbon, titanium aluminum and titanium silicon.

9. The method of claim 1, wherein: in the hydrodesulfurization catalyst, the carrier is alumina.

10. The method of claim 1, wherein: the properties of the hydrodesulfurization catalyst are as follows: the specific surface area is 50-300m ² The pore volume is 0.4-1.2mL/g.

11. The method of claim 1, wherein: the properties of the hydrodesulfurization catalyst are as follows: the specific surface area is 100-240m ² The pore volume is 0.5-1.0mL/g.

12. The method of claim 1, wherein: in the hydrodenitrogenation catalyst, the content of the VIII group metal in terms of oxide is 1.0-6.0% and the content of molybdenum in terms of oxide is 8.0-25.0% on the basis of the weight of the carrier.

13. A method according to claim 1 or 12, characterized by: in the hydrodenitrogenation catalyst, at least part of molybdenum element exists in the catalyst in the form of molybdenum carbonyl, and the molybdenum existing in the form of molybdenum carbonyl accounts for 50-90% of the total molybdenum.

14. The method of claim 1, wherein: in the hydrodenitrogenation catalyst, the form of molybdenum element existing in the catalyst comprises carbonyl molybdenum and molybdenum oxide, wherein the ratio of the carbonyl molybdenum to the molybdenum oxide in terms of molybdenum atoms is 7:3-9:1.

15. the method of claim 1, wherein: in the hydrodenitrogenation catalyst, the VIII group metal is at least one selected from nickel and cobalt, and the complexing agent is one or more selected from ammonia water, urea, glycine, triethanolamine, ethylenediamine tetraacetic acid, nitrilotriacetic acid, N-methylacetamide and N-methylformamide.

16. A method according to claim 1 or 15, characterized by: in the hydrodenitrogenation catalyst, the content of the complexing agent is 50% -200% of the theoretical complexing amount of the VIII group metal.

17. A method according to claim 1 or 15, characterized by: in the hydrodenitrogenation catalyst, the content of the complexing agent is 70-150% of the theoretical complexing amount of the VIII group metal.

18. The method of claim 1, wherein: in the hydrodenitrogenation catalyst, the carrier is at least one of alumina, silicon oxide, a molecular sieve, activated carbon, titanium aluminum and titanium silicon.

19. The method of claim 1, wherein: in the hydrodenitrogenation catalyst, the carrier is alumina.

20. The method of claim 1, wherein: the properties of the hydrodenitrogenation catalyst are as follows: the specific surface area is 120-300m ² The pore volume is 0.3-1.2mL/g, the total acid amount is 0.3-1.2mmol/g, the content of strong acid is 5% -40% of the total acid amount, and the content of medium strong acid is 5% -40% of the total acid amount.

21. The method of claim 1, wherein: and loading a hydrogenation protective agent and a hydrogenation demetalization catalyst before the hydrogenation desulfurization catalyst.

22. The method of claim 1, wherein: the filling volume of the hydrodesulfurization catalyst and the hydrodenitrogenation catalyst accounts for more than 60 percent of the total catalyst filling volume.

23. The method of claim 1, wherein: the residua feedstock comprises atmospheric resid and/or vacuum resid.

24. The method of claim 1, wherein: the fixed bed hydroprocessing conditions were as follows: the reaction temperature is 320-400 ℃, the reaction pressure is 6.0-25.0 MPa, the hydrogen-oil volume ratio is 200 ^-1 。

25. The method of claim 1, wherein: and (3) hydrogenating the residual oil to obtain hydrogenated oil serving as a feed of a catalytic cracking unit or a feed of a hydrocracking unit.