CN111073689B

CN111073689B - Heavy oil hydrotreating method

Info

Publication number: CN111073689B
Application number: CN201811226389.6A
Authority: CN
Inventors: 吕振辉; 彭绍忠; 杨占林; 隋宝宽; 薛冬
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: 2018-10-22
Filing date: 2018-10-22
Publication date: 2021-10-08
Anticipated expiration: 2038-10-22
Also published as: CN111073689A

Abstract

The invention discloses a heavy oil hydrotreating method, which comprises the following steps: the heavy oil raw material enters a hydrogenation reactor, contacts with a hydrogenation catalyst bed layer to carry out hydrogenation reaction, and a reaction product flows out of the reactor; the hydrogenation catalyst bed layer is filled with at least two stages of sulfide state hydrogenation catalysts in a grading way along the material flow direction, and each stage of sulfide state hydrogenation catalysts is gradually increased in average length of metal active phase lamella, gradually reduced in average layer number of the lamella, gradually increased in active component content and gradually reduced in aperture. The method of the invention adopts specific catalyst gradation, can effectively utilize the active center of the catalyst, improve the coupling reaction performance of the active center structure and the reactant molecular structure, greatly improve the stability of the hydrogenation reaction of the whole system, such as demetalization, desulfurization, denitrification and the like, and is beneficial to deep hydrogenation of heavy oil.

Description

Heavy oil hydrotreating method

Technical Field

The invention relates to a heavy oil hydrotreating method.

Background

In the heavy oil hydrotreating, the catalyst is generally loaded in a grading way, and the catalyst is generally a protective agent, a demetallization catalyst, a desulfurization catalyst and a denitrification catalyst in sequence. The grading filling of the catalyst can not only increase the scale holding capacity of the catalyst bed layer, but also obviously reduce the pressure drop of the catalyst bed layer. The catalyst grading filling technology can increase the metal capacity of the catalyst system, and because the upstream demetallization catalyst effectively plays a demetallization function, the hydrogenation activity of the downstream high-activity desulfurizer or denitrifier is protected, so the catalyst grading filling technology can increase the hydrogenation capacity of the residual oil hydrotreating catalyst on heavy raw materials.

The reactions in the heavy oil hydrotreating process mainly include hydrodesulfurization, hydrodenitrogenation, hydrodemetallization, aromatics saturation, and hydrocracking of various hydrocarbons. When the heavy raw material enters the reactor, the molecular structure of the reactant is complex, the steric hindrance is large, and impurities are easy to remove; along with hydrogenation and hydrogenolysis reactions, reactant molecules are subjected to ring opening and chain breaking gradually, the molecular structure is simplified gradually, the steric hindrance is small, and impurities are more difficult to remove. The prior heavy oil hydrogenation catalyst grading method is usually researched from the aspect of appearance level, namely catalyst particle size, pore channel size, activity transition and the like, and is not considered from the aspect of actual reactant molecular structure, and along with the reaction, the reactant molecular structure and the catalyst structure cannot be well matched, so that the depth of hydrogenation reaction is limited.

CN103045302A discloses a grading scheme of a hydrotreating catalyst, which comprises the steps of sequentially passing a residual oil raw material and hydrogen through a protective agent, a demetallization catalyst 1, a desulfurization catalyst and a denitrification catalyst, and then passing through a demetallization catalyst 2, wherein the filling volume of the demetallization catalyst 2 accounts for 10-30% of the total filling volume. The product passing through the demetallization catalyst 2 can be continuously subjected to deep desulfurization by a wax oil hydrogenation catalyst. The method can reduce the content of metal and carbon residue in the residual oil hydrogenation product, but can not achieve the purpose of deep desulfurization.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a heavy oil hydrotreating method, which adopts specific catalyst gradation, can effectively utilize the catalyst active center, improve the coupling reaction performance of the active center structure and the reactant molecular structure, greatly improve the stability of the whole system hydrogenation reaction, such as demetalization, desulfurization, denitrification and the like, and is beneficial to deep hydrogenation of the heavy oil.

The heavy oil hydrotreating method of the invention comprises the following steps: the heavy oil raw material enters a hydrogenation reactor, contacts with a hydrogenation catalyst bed layer to carry out hydrogenation reaction, and a reaction product flows out of the reactor; the hydrogenation catalyst bed layer is filled with at least two stages of sulfurized hydrogenation catalysts in a grading way along the material flow direction, and each stage of sulfurized hydrogenation catalyst is gradually increased in average length of metal active phase platelets, gradually reduced in average layer number of the platelets, gradually increased in active component content and gradually reduced in aperture; the metal active phase is active metal sulfide; the vulcanized hydrogenation catalyst is obtained by vulcanizing the oxidized hydrogenation catalyst.

In the process of the present invention, the heavy oil feedstock is a heavy distillate oil such as vacuum wax oil (VGO), coker wax oil (CGO), solvent deasphalted oil (DAO), etc., as well as Atmospheric Residue (AR), Vacuum Residue (VR), coal tar, etc.

In the method of the present invention, the oxidation state hydrogenation catalyst is generally a heavy oil hydrogenation catalyst commonly used in the art, such as a hydrogenation protective agent, a hydrodenitrogenation agent, a hydrodemetalization agent, and the like, generally alumina or modified alumina is used as a carrier, a group VIII and/or group VIB metal element is used as an active component, based on the weight of the catalyst, the active metal is calculated as an oxide, the group VIII metal is 1wt% to 9wt%, preferably 1.0wt% to 9.0wt%, and the group VIB metal is 5wt% to 25wt%, and may be selected from the catalysts prepared by the method of the present invention or commercially available products, such as FZC-28, FZC-204, FZC-33, FZC-41, FZC-24, FF-34, and the like.

In the method of the invention, the oxidation state hydrogenation catalyst has the following properties: specific surface area of 100 to 250m²A pore volume of 0.3 to 1.0 mL/g^-1The pore diameter is not less than 5 nm.

In the method, the average length of the metal active phase lamella of each stage of the vulcanization catalyst is 1-9 nm, and the gradual increase amplitude is 1-5 nm, preferably 2-4 nm.

In the method, the average number of layers of metal active phase platelets of each stage of the vulcanization catalyst is 1-9, and the stepwise reduction range is 1-5, preferably 2-4.

In the method, the content of the metal active components of each stage of the vulcanization catalyst is gradually increased, and the range is 3-15 wt%, preferably 10-15 wt%.

In the method, the gradually-decreasing range of the pore diameters of the sulfidation catalysts at each stage is 1-10 nm.

In the method, the filling proportion of each level of the sulfided catalyst is at least 10 percent based on the total volume of the catalyst in the reactor. Along the material flow direction, when the two-stage filling proportion is: 10% -90%: 10% -90%; the third-level filling proportion is 10% -90%: 10% -40%: 20 to 80 percent; the four-stage filling proportion is as follows: 10% -40%: 10% -40%: 10% -40%: 10 to 40 percent, and the sum of the filling proportions of all levels is 100 percent.

In the method, the vulcanization mode can adopt wet vulcanization or dry vulcanization, and the temperature rise speed, the vulcanization temperature and the vulcanization time in the vulcanization process are adjusted according to the required metal active phase platelet structure.

In the method, preferably, 3-4 stages of sulfurized hydrogenation catalysts are sequentially loaded, and taking the loading of 3 stages as an example, the sulfurized hydrogenation catalysts I, II and III are sequentially loaded along the material flow direction.

Wherein the properties of the hydrogenation catalyst I in a sulfurized state are as follows: the aluminum oxide catalyst comprises an aluminum oxide carrier and active metals, wherein the active metals are selected from one or more of VIII group and/or VIB group metal elements; based on the weight of the catalyst, the active metal is calculated by oxide, the VIII group metal is 1wt% -9 wt%, preferably 1.0wt% -3.0 wt%, the VIB group metal is 5wt% -25 wt%, preferably 8wt% -12 wt%, and the balance is an alumina carrier. The average number of layers of the active photo is 7.0-9.0, and the average length of the photo is 1.0-3.0 nm. The specific surface area is 100-140 m²A pore volume of 0.8 to 1.0 ml/g^-1(ii) a The pore diameter is not less than 15 nm. The hydrogenation catalyst I in the oxidized state can be prepared by using a commercial product or according to the existing method, such as the following method: and supersaturating and dipping the alumina carrier by using a solution containing an active metal component to obtain a catalyst precursor, and drying and roasting to obtain the required oxidation state hydrogenation catalyst I. The drying temperature is 100-300 ℃, preferably 200-300 ℃, and the drying time is 1-5 h, preferably 4-5 h; the roasting temperature is 500-600 ℃, preferably 550-580 ℃, and the roasting time is 1-5 h, preferably 4-5 h; the heating rate is 2-5 ℃/min.

The preparation method of the vulcanized hydrogenation catalyst I comprises the following steps: filling an oxidation state catalyst I into a vulcanization reactor, introducing vulcanized oil into the vulcanization reactor, and wetting a catalyst bed layer; then adjusting the temperature of the bed layer to 150-170 ℃, and injecting a vulcanizing agent; after hydrogen sulfide penetrates through the catalyst bed layer, raising the temperature of the catalyst bed layer to 250-270 ℃ at the speed of 2-5 ℃/h, and keeping the temperature for 8-10 hours; and raising the temperature of the catalyst bed to 350-360 ℃ at the speed of 5-10 ℃/h, and keeping the temperature for 8-10 hours.

The vulcanized hydrogenation catalyst II has the following properties: comprises an alumina carrier and active goldThe metal is one or more of VIII group and/or VIB group metal elements; based on the weight of the catalyst, the active metal is calculated by oxide, the VIII group metal is 1wt% -9 wt%, preferably 3.0wt% -5.0 wt%, the VIB group metal is 5wt% -25 wt%, preferably 15wt% -20 wt%, and the balance is an alumina carrier. The average number of layers of the active photo is 4.0-6.0, and the average length of the photo is 4.0-6.0 nm. The specific surface area is 150-180 m²A pore volume of 0.7 to 0.8 ml/g^-1(ii) a The pore diameter of the porous material can be 10-15 nm. The hydrogenation catalyst II in the oxidized state can be prepared by using a commercial product or according to the existing method, such as the following method: impregnating the catalyst support with an organic compound solution; heat-treating the obtained organic compound additive-loaded support; and loading the active metal component on the obtained organic matter-loaded carrier to obtain a catalyst precursor, and drying and roasting the catalyst precursor to obtain the required oxidation state hydrogenation catalyst II. The organic compound may specifically be a compound containing at least two oxygen atom groups and 2 to 5 carbon atoms. In particular compounds containing at least two hydroxyl groups and 2 to 5 carbon atoms. Suitable organic additives include, for example, alcohols, ethers or sugars, for example, suitable alcohols may include ethylene glycol, propylene glycol, glycerol, and the like, suitable ethers may include diethylene glycol, propylene glycol, and the like, and suitable sugars include monosaccharides. One or more of the organic compounds may be selected. The drying temperature is 100-300 ℃, preferably 150-200 ℃, and the drying time is 1-5 h, preferably 2-3 h; the roasting temperature is 400-500 ℃, preferably 450-480 ℃, and the roasting time is 1-5 h, preferably 2-3 h; the temperature rise rate is 5-10 ℃/min. The dosage of the organic compound is 5-10% of the weight of the catalyst carrier.

The preparation method of the vulcanized hydrogenation catalyst II comprises the following steps: filling an oxidation state hydrogenation catalyst II into a vulcanization reactor, introducing vulcanized oil into the vulcanization reactor, and wetting a catalyst bed layer; then adjusting the temperature of the bed layer to 150-170 ℃, and injecting a vulcanizing agent; after hydrogen sulfide penetrates through the catalyst bed layer, raising the temperature of the catalyst bed layer to 210-230 ℃ at a speed of 5-10 ℃/h, and keeping the temperature for 5-7 hours; and raising the temperature of the catalyst bed to 330-340 ℃ at a speed of 10-15 ℃/h, and keeping the temperature for 5-7 hours.

The properties of the vulcanized hydrogenation catalyst III are as follows: the aluminum oxide catalyst comprises an aluminum oxide carrier and active metals, wherein the active metals are selected from one or more of VIII group and/or VIB group metal elements; based on the weight of the catalyst, the active metal is calculated by oxide, the VIII group metal is 1wt% -9 wt%, preferably 5.0wt% -9.0 wt%, the VIB group metal is 5wt% -25 wt%, preferably 21wt% -25 wt%, and the balance is an alumina carrier. The average number of layers of the active photo is 1.0-3.0, and the average length of the photo is 7.0-9.0 nm. The specific surface area is 190-210 m²A pore volume of 0.4 to 0.6 ml/g^-1(ii) a The pore diameter of the porous material can be 5.0-9.0 nm. The hydrogenation catalyst III in the oxidized state can be prepared by using a commercial product or according to the existing method, such as the following method: and (3) saturating and dipping the alumina carrier by using a solution containing an active metal component and an organic compound to obtain a catalyst precursor, and drying to obtain the required oxidation state hydrogenation catalyst III. The organic compound may specifically be a compound containing at least two oxygen atom groups and 5 to 20 carbon atoms. In particular compounds containing at least two hydroxyl groups and 5 to 20 carbon atoms. Suitable organic additives include, for example, alcohols, ethers or sugars, for example, suitable alcohols may include glycerol and the like, suitable ethers may include triethylene glycol, tributylene glycol or tetraethylene glycol and the like, suitable sugars include polysaccharides, which may include lactose, maltose or sucrose. One or more of the organic compounds may be selected. The drying temperature is 100-300 ℃, preferably 100-150 ℃, and the drying time is 1-5 h, preferably 1-1.5 h; the heating rate is 2-5 ℃/min. The dosage of the organic compound is 15-20% of the weight of the catalyst carrier.

The preparation method of the vulcanized hydrogenation catalyst III comprises the following steps: filling the oxidation state catalyst into a vulcanization reactor, introducing vulcanized oil into the vulcanization reactor, and wetting a catalyst bed layer; then adjusting the temperature of the bed layer to 150-170 ℃, and injecting a vulcanizing agent; after hydrogen sulfide penetrates through the catalyst bed layer, raising the temperature of the catalyst bed layer to 180-200 ℃ at a speed of 10-15 ℃/h, and keeping the temperature for 2-4 hours; and raising the temperature of the catalyst bed to 310-320 ℃ at a speed of 15-20 ℃/h, and keeping the temperature for 2-4 hours.

Based on the weight of all the catalysts, the proportion of the vulcanized hydrogenation catalyst I is 10-90%, the proportion of the vulcanized hydrogenation catalyst II is 10-40%, and the proportion of the vulcanized hydrogenation catalyst III is 20-80%. The filling method of the hydrogenation catalyst grading system generally adopts bag filling or dense phase filling, and is conventional operation in the field.

The catalyst grading process of the present invention can be used under any hydroprocessing conditions suitable in the art. Typical hydrotreating process conditions are: the average reaction temperature is 330-450 ℃, preferably 350-430 ℃; the reaction hydrogen partial pressure is 8.0-20.0 MPa, preferably 10.0-18.0 MPa; liquid hourly volume space velocity of 0.15h^-1～3.0h^-1Preferably 0.2h^-1～2.0h^-1(ii) a The volume ratio of hydrogen to oil is 300-1500, preferably 500-1200.

Compared with the prior art, the heavy oil hydrotreating catalyst grading method provided by the invention has the following advantages:

1. in the method, the catalysts with various active phase structures are graded in sections according to the sizes and the structures of the reactant molecules along the flowing direction of the reactant, so that the coupling reaction of the sizes and the structures of the reactant molecules and the active phase structures is realized, the utilization rate of active metals is improved, and the technical problem that the molecules and the structures of the reactant contradict with the active phase structures is solved.

2. In the method, along the flowing direction of reactants, the reactants which are firstly contacted with the catalyst, such as polycyclic thiophene sulfides, heterocyclic nitrides, polycyclic aromatic hydrocarbon compounds and the like, have more complex structures and larger steric hindrance, and reaction impurities are difficult to remove under the influence of the steric hindrance, so that the metal active photo crystal of the catalyst adopting the method has shorter length and more layers, can obviously reduce the steric hindrance effect, improve the utilization rate of an active phase and ensure that the impurities with larger steric hindrance are easier to remove;

3. in the method, the molecular structure of the reactant is simplified and the steric hindrance is reduced through the preliminary hydrogenation reaction, so that the catalyst adopting the method has moderate metal active photo crystal length and moderate number of layers of the photo crystal, can be coupled with the reaction molecule of the structure more effectively for reaction, and further improves the reaction performance on the reactant molecule;

4. in the method, molecules subjected to final hydrogenation and hydrogenolysis reaction are subjected to ring opening and chain scission to form micromolecular reactants which have simple structures and smaller steric hindrance and are difficult to react, such as thiophene sulfides, monocyclic nitrides and monocyclic, bicyclic or tricyclic aromatic compounds, and finally the catalyst adopting the method has longer metal active photo crystal length and fewer layers of the photo crystal, further performs hydrogenation reaction on the micromolecules with smaller steric hindrance to remove impurities contained in the micromolecules which are difficult to remove, improves the utilization rate of active metals, and realizes effective reaction on reactant molecules;

5. the catalyst preparation method and the grading technology adopted in the method can obviously improve the utilization rate of active metal of the catalyst, and improve the desulfurization, denitrification and aromatic hydrocarbon saturation performance of the system.

Drawings

FIG. 1 is a TEM photograph of a sulfidation catalyst I in example 1 of the present invention.

FIG. 2 is a TEM photograph of a sulfidation catalyst II in example 1 of the present invention.

FIG. 3 is a TEM photograph of a sulfiding catalyst III in example 1 of the present invention.

Detailed Description

The preparation and grading process of the hydrogenation catalyst of the present invention is described in more detail below by way of specific examples. The examples are merely illustrative of specific embodiments of the process of the present invention and do not limit the scope of the invention. In the method, the average length and the average layer number of the platelets of the vulcanized catalyst are subjected to statistical analysis by adopting a Transmission Electron Microscope (TEM) (30 transmission electron microscope pictures are subjected to manual statistics to obtain an average value); the pore structure of the catalyst is determined by nitrogen adsorption-desorption. The carrier I used in the examples and comparative examples is an alumina carrier having a specific surface area of 140 to 160m²(iii) a pore volume of 0.95 to 1.0 mL/g^-1(ii) a The pore diameter of the carrier II is 18-21 nm, the carrier II is an alumina carrier, and the specific surface area of the carrier is 170-190 m²(iii) a pore volume of 0.85 to 0.95 mL/g^-1(ii) a The pore diameter of the carrier III is 15-17 nm, the carrier III is an alumina carrier, and the specific surface area of the carrier III is 200-300 m²(iii) a pore volume of 0.70 to 0.85 mL/g^-1(ii) a The aperture of the filter can be 10-15 nm; the vulcanizing agent is DMDS.

Example 1

This example shows a catalyst grading combination and a preparation of a graded catalyst. By adopting a catalyst grading scheme, a reactor is filled with a catalyst, and a bed layer is filled with a sulfurized hydrogenation catalyst I, a sulfurized hydrogenation catalyst II and a sulfurized hydrogenation catalyst III from top to bottom.

The preparation method of the vulcanized hydrogenation catalyst I comprises the following steps: the carrier I is added with a carrier containing MoO₃And supersaturation impregnation is carried out on the active component of NiO to obtain a catalyst precursor, the precursor is dried for 4h at the temperature of 250 ℃, the temperature is raised to 580 ℃ at the speed of 5 ℃/min, and the catalyst is roasted at constant temperature for 4.5h to obtain the required catalyst. The catalyst MoO₃12.0 percent of NiO and 2.1 percent of NiO; the specific surface area is 120m²Per g, pore volume of 0.87 ml.g^-1(ii) a The pore diameter can be 17.8 nm. Filling the catalyst into a vulcanization reactor, introducing vulcanized oil into the vulcanization reactor, and wetting a catalyst bed layer; then adjusting the temperature of the bed layer to 170 ℃, and injecting a vulcanizing agent; after hydrogen sulfide penetrates through the catalyst bed layer, raising the temperature of the catalyst bed layer to 250 ℃ at the speed of 5 ℃/h, and keeping the temperature for 8 hours; the temperature of the catalyst bed is raised to 360 ℃ at the speed of 10 ℃/h, and the temperature is kept constant for 8 hours. The average number of layers of the active photo is 8.7, and the average length of the plate is 2.3 nm.

The preparation method of the vulcanized hydrogenation catalyst II comprises the following steps: the carrier II contains MoO₃And saturating and dipping the mixed solution of the active component of NiO and diglycol (the dosage is 6 percent of the mass of the catalyst carrier) to obtain a catalyst precursor, drying the precursor at 180 ℃ for 2.5h, heating to 450 ℃ at 5 ℃/min, and roasting at constant temperature for 3.0h to obtain the required catalyst. The catalyst MoO₃18.0 percent and 3.3 percent of NiO; specific surface area 175m²Per g, pore volume of 0.71ml g^-1(ii) a The aperture of the micro-porous membrane is 12.8 nm. Filling the catalyst into a vulcanization reactor, introducing vulcanized oil into the vulcanization reactor, and wetting a catalyst bed layer; then adjusting the temperature of the bed layer to 160 ℃, and injecting a vulcanizing agent; to be penetrated by hydrogen sulfideAfter the catalyst bed layer, the temperature of the catalyst bed layer is increased to 230 ℃ at the speed of 10 ℃/h, and the constant temperature is kept for 6 hours; the temperature of the catalyst bed is raised to 340 ℃ at a speed of 15 ℃/h, and the temperature is kept constant for 6 hours. The average number of layers of the active photo is 5.7, and the average length of the plate crystal is 4.9 nm.

The preparation method of the vulcanized hydrogenation catalyst III comprises the following steps: the carrier III is treated with a solution containing MoO₃And saturating and dipping the mixed solution of the active component of NiO and cane sugar (the dosage is 16 percent of the mass of the catalyst carrier) to obtain a catalyst precursor, and drying the precursor at 120 ℃ for 1.5h to obtain the required catalyst. The catalyst MoO₃21.0 percent and 5.7 percent of NiO; the specific surface area is 190m²Per g, pore volume of 0.55ml g^-1(ii) a The aperture of the glass can be as small as 8.7 nm. Filling the catalyst into a vulcanization reactor, introducing vulcanized oil into the vulcanization reactor, and wetting a catalyst bed layer; then adjusting the temperature of the bed layer to 160 ℃, and injecting a vulcanizing agent; after hydrogen sulfide penetrates through the catalyst bed layer, raising the temperature of the catalyst bed layer to 200 ℃ at a speed of 15 ℃/h, and keeping the temperature for 4 hours; the temperature of the catalyst bed is raised to 320 ℃ at the speed of 20 ℃/h, and the temperature is kept constant for 4 hours. The average number of layers of the active photo is 2.4, and the average length of the plate crystal is 8.1 nm.

Example 2

The same as example 1, except that the preparation method of the hydrogenation catalyst I, II in a sulfurized state and III is different, specifically:

the preparation method of the vulcanized hydrogenation catalyst I comprises the following steps: the carrier I is added with a carrier containing MoO₃And supersaturation impregnation is carried out on the active component of NiO to obtain a catalyst precursor, the precursor is dried for 5h at the temperature of 300 ℃, the temperature is raised to 550 ℃ at the speed of 4 ℃/min, and the required catalyst is obtained after constant-temperature roasting for 4.5 h. The catalyst MoO₃11.0 percent of NiO and 2.8 percent of NiO; the specific surface area is 130m²Per g, pore volume of 0.91ml g^-1(ii) a The aperture of the glass can be 21.5 nm. Filling the catalyst into a vulcanization reactor, introducing vulcanized oil into the vulcanization reactor, and wetting a catalyst bed layer; then adjusting the temperature of the bed layer to 170 ℃, and injecting a vulcanizing agent; after hydrogen sulfide penetrates through the catalyst bed layer, raising the temperature of the catalyst bed layer to 260 ℃ at the speed of 3 ℃/h, and keeping the temperature for 8 hours; the temperature of the catalyst bed is raised to 360 ℃ at the speed of 5 ℃/h, and the temperature is kept for 9 hours. The average number of layers of the active photo crystal is 7.9, and the photo crystal is a plate crystalThe average length was 2.5 nm.

The preparation method of the vulcanized hydrogenation catalyst II comprises the following steps: the carrier II contains MoO₃And saturating and dipping the mixed solution of the active component of NiO and glucose (the dosage is 8 percent of the mass of the catalyst carrier) to obtain a catalyst precursor, drying the precursor at 150 ℃ for 3.0h, heating to 470 ℃ at the speed of 10 ℃/min, and roasting at constant temperature for 2.0h to obtain the required catalyst. The catalyst MoO₃20.0 percent and 3.7 percent of NiO; the specific surface area is 150m²Per g, pore volume of 0.80ml g^-1(ii) a The aperture of the glass can be 11.9 nm. Filling the catalyst into a vulcanization reactor, introducing vulcanized oil into the vulcanization reactor, and wetting a catalyst bed layer; then adjusting the temperature of the bed layer to 170 ℃, and injecting a vulcanizing agent; after hydrogen sulfide penetrates through the catalyst bed layer, raising the temperature of the catalyst bed layer to 210 ℃ at the speed of 8 ℃/h, and keeping the temperature for 6 hours; the temperature of the catalyst bed is increased to 340 ℃ at the speed of 11 ℃/h, and the temperature is kept constant for 5 hours. The average number of layers of the active photo is 4.8, and the average length of the plate is 5.5 nm.

The preparation method of the vulcanized hydrogenation catalyst III comprises the following steps: the carrier III is treated with a solution containing MoO₃And saturating and dipping the mixed solution of the active component of NiO and tributyl glycol (the dosage is 20 percent of the mass of the catalyst carrier) to obtain a catalyst precursor, and drying the precursor at 100 ℃ for 1.0h to obtain the required catalyst. The catalyst MoO₃24.8 percent of NiO and 5.5 percent of NiO; specific surface area of 191m²Per g, pore volume of 0.46ml g^-1(ii) a The aperture of the glass can be 7.8 nm. Filling the catalyst into a vulcanization reactor, introducing vulcanized oil into the vulcanization reactor, and wetting a catalyst bed layer; then adjusting the temperature of the bed layer to 170 ℃, and injecting a vulcanizing agent; after hydrogen sulfide penetrates through the catalyst bed layer, raising the temperature of the catalyst bed layer to 200 ℃ at a speed of 10 ℃/h, and keeping the temperature for 4 hours; the temperature of the catalyst bed is raised to 320 ℃ at a speed of 17 ℃/h, and the temperature is kept constant for 3 hours. The average number of layers of the active photo is 2.0, and the average length of the plate crystal is 7.9 nm.

Example 3

The same as example 2, except that the preparation method of the hydrogenation catalyst III in a sulfurized state is different, specifically:

the same as in example 2.

Sulphurised state hydrogenation catalysisThe preparation method of the agent III comprises the following steps: the carrier III is treated with a solution containing MoO₃And saturating and impregnating the mixed solution of the active component of NiO and lactose (the dosage is 17 percent of the mass of the catalyst carrier) to obtain a catalyst precursor, and drying the precursor at 120 ℃ for 1.5h to obtain the required catalyst. The catalyst MoO₃24.9 percent of NiO and 5.8 percent of NiO; specific surface area of 198m²Per g, pore volume of 0.55ml g^-1(ii) a The aperture of the glass can be as small as 8.1 nm. Filling the catalyst into a vulcanization reactor, introducing vulcanized oil into the vulcanization reactor, and wetting a catalyst bed layer; then adjusting the temperature of the bed layer to 160 ℃, and injecting a vulcanizing agent; after hydrogen sulfide penetrates through the catalyst bed layer, raising the temperature of the catalyst bed layer to 200 ℃ at a speed of 15 ℃/h, and keeping the temperature for 4.5 hours; the temperature of the catalyst bed is raised to 310 ℃ at 20 ℃/h and kept constant for 2 hours. The average number of layers of the active photo is 1.5, and the average length of the plate crystal is 8.7 nm.

Example 4

The same as example 2, except that the preparation method of the hydrogenation catalysts II and III in a sulfurized state is different, specifically:

the preparation method of the vulcanized hydrogenation catalyst I comprises the following steps: the same as in example 2.

The preparation method of the vulcanized hydrogenation catalyst II comprises the following steps: the carrier II contains MoO₃And saturating and dipping the mixed solution of the active component of NiO and glucose (the dosage is 10 percent of the mass of the catalyst carrier) to obtain a catalyst precursor, drying the precursor at 170 ℃ for 2.0h, heating to 450 ℃ at 10 ℃/min, and roasting at constant temperature for 2.5h to obtain the required catalyst. The catalyst MoO₃19.0 percent and 4.8 percent of NiO; the specific surface area is 160m²Per g, pore volume of 0.77ml g^-1(ii) a The aperture of the glass can be 10.8 nm. Filling the catalyst into a vulcanization reactor, introducing vulcanized oil into the vulcanization reactor, and wetting a catalyst bed layer; then adjusting the temperature of the bed layer to 170 ℃, and injecting a vulcanizing agent; after hydrogen sulfide penetrates through the catalyst bed layer, raising the temperature of the catalyst bed layer to 220 ℃ at a speed of 10 ℃/h, and keeping the temperature for 7 hours; the temperature of the catalyst bed is raised to 330 ℃ at a speed of 15 ℃/h, and the temperature is kept constant for 6 hours. The average number of layers of the active photo is 5.0, and the average length of the plate is 5.9 nm.

The preparation method of the vulcanized hydrogenation catalyst III comprises the following steps:the carrier III is treated with a solution containing MoO₃And saturating and dipping the mixed solution of the active component of NiO and lactose (the dosage is 20 percent of the mass of the catalyst carrier) to obtain a catalyst precursor, and drying the precursor at 120 ℃ for 1.0h to obtain the required catalyst. The catalyst MoO₃25.0 percent and NiO 6.5 percent; specific surface area is 197m²Per g, pore volume of 0.50ml g^-1(ii) a The pore diameter can be 7.5 nm. Filling the catalyst into a vulcanization reactor, introducing vulcanized oil into the vulcanization reactor, and wetting a catalyst bed layer; then adjusting the temperature of the bed layer to 160 ℃, and injecting a vulcanizing agent; after hydrogen sulfide penetrates through the catalyst bed layer, raising the temperature of the catalyst bed layer to 180 ℃ at 18 ℃/h, and keeping the temperature for 3 hours; the temperature of the catalyst bed is raised to 310 ℃ at a speed of 15 ℃/h, and the temperature is kept constant for 3.5 hours. The average number of layers of the active photo is 2.0, and the average length of the plate crystal is 8.1 nm.

Example 5

The same as example 1, except that only the hydrogenation catalysts II and III in a sulfurized state are filled in the reactor, and the preparation methods of the hydrogenation catalysts II and III in a sulfurized state are different, specifically:

the preparation method of the vulcanized hydrogenation catalyst II comprises the following steps: the carrier II contains MoO₃And saturating and dipping the mixed solution of the active component of NiO and glucose (the dosage is 10 percent of the mass of the catalyst carrier) to obtain a catalyst precursor, drying the precursor at 170 ℃ for 2.0h, heating to 450 ℃ at 10 ℃/min, and roasting at constant temperature for 2.5h to obtain the required catalyst. The catalyst MoO₃19.0 percent and 4.8 percent of NiO; the specific surface area is 170m²Per g, pore volume of 0.75ml g^-1(ii) a The pore diameter can be as small as 11.2 nm. Filling the catalyst into a vulcanization reactor, introducing vulcanized oil into the vulcanization reactor, and wetting a catalyst bed layer; then adjusting the temperature of the bed layer to 170 ℃, and injecting a vulcanizing agent; after hydrogen sulfide penetrates through the catalyst bed layer, raising the temperature of the catalyst bed layer to 210 ℃ at a speed of 10 ℃/h, and keeping the temperature for 6.5 hours; the temperature of the catalyst bed was raised to 340 ℃ at 15 ℃/h and maintained at that temperature for 7 hours. The average number of layers of the active photo is 5.5, and the average length of the plate is 5.4 nm.

The preparation method of the vulcanized hydrogenation catalyst III comprises the following steps: the carrier III is treated with a solution containing MoO₃NiO, and lactoseThe dosage of the mixed solution is 20 percent of the mass of the catalyst carrier), saturated and impregnated to obtain a catalyst precursor, and the precursor is dried at 120 ℃ for 1.0h to obtain the required catalyst. The catalyst MoO₃25.0 percent and NiO 6.5 percent; specific surface area of 198m²Per g, pore volume of 0.51ml g^-1(ii) a The aperture of the glass can be as small as 8.5 nm. Filling the catalyst into a vulcanization reactor, introducing vulcanized oil into the vulcanization reactor, and wetting a catalyst bed layer; then adjusting the temperature of the bed layer to 160 ℃, and injecting a vulcanizing agent; after hydrogen sulfide penetrates through the catalyst bed layer, raising the temperature of the catalyst bed layer to 190 ℃ at 18 ℃/h, and keeping the temperature for 2 hours; the temperature of the catalyst bed is raised to 320 ℃ at the speed of 15 ℃/h, and the temperature is kept for 2.5 hours. The average number of layers of the active photo is 2.2, and the average length of the plate crystal is 8.0 nm.

Comparative example 1

The same as example 1, except that the preparation methods of the hydrogenation catalysts I, II and III are different, specifically:

the preparation method of the hydrogenation catalyst I comprises the following steps: the carrier I is added with a carrier containing MoO₃And supersaturation impregnation is carried out on the active component of NiO to obtain a catalyst precursor, the precursor is dried for 5h at the temperature of 300 ℃, the temperature is raised to 550 ℃ at the speed of 4 ℃/min, and the required catalyst is obtained after constant-temperature roasting for 4.5 h. The catalyst MoO₃12.0 percent and 2.7 percent of NiO; the specific surface area is 120m²Per g, pore volume of 0.85ml g^-1(ii) a The pore diameter can be as small as 20.8 nm.

The preparation method of the hydrogenation catalyst II comprises the following steps: the carrier II contains MoO₃And supersaturation dipping the active component solution of NiO to obtain a catalyst precursor, drying the precursor at 300 ℃ for 5h, heating to 550 ℃ at 4 ℃/min, and roasting at constant temperature for 4.5h to obtain the required catalyst. The catalyst MoO₃18.7 percent of NiO and 4.6 percent of NiO; the specific surface area is 170m²Per g, pore volume of 0.78ml g^-1(ii) a The pore diameter can be as small as 11.2 nm.

The preparation method of the hydrogenation catalyst III comprises the following steps: the carrier III is treated with a solution containing MoO₃And supersaturation dipping the active component solution of NiO to obtain a catalyst precursor, drying the precursor at 300 ℃ for 5h, heating to 550 ℃ at 4 ℃/min, and roasting at constant temperature for 4.5h to obtain the required catalyst. The catalyst MoO₃Is 24.5 percent of the total weight of the mixture,NiO is 6.7 percent; the specific surface area is 190m²Per g, pore volume of 0.54ml g^-1(ii) a The pore diameter can be 7.6 nm.

Filling a hydrogenation catalyst I, a hydrogenation catalyst II and a hydrogenation catalyst III into a vulcanization reactor from top to bottom according to a proportion, introducing vulcanized oil into the vulcanization reactor, and wetting a catalyst bed layer; then adjusting the temperature of the bed layer to 160 ℃, and injecting a vulcanizing agent; after hydrogen sulfide penetrates through the catalyst bed layer, raising the temperature of the catalyst bed layer to 250 ℃ at the speed of 5 ℃/h, and keeping the temperature for 8 hours; the temperature of the catalyst bed is raised to 360 ℃ at the speed of 10 ℃/h, and the temperature is kept constant for 8 hours. The average number of layers of active photo crystals of the hydrogenation catalyst I is 7.9, and the average length of the photo crystals is 2.5 nm; the average number of layers of active photo crystals of the hydrogenation catalyst II is 8.8, and the average length of the photo crystals is 2.8 nm; the average number of layers of active photo crystal of hydrogenation catalyst III is 8.2, and the average length of the photo crystal is 1.9 nm.

Comparative example 2

the preparation method of the hydrogenation catalyst I comprises the following steps: the carrier I is added with a carrier containing MoO₃And saturating and dipping the mixed solution of the active component of NiO and glycol (the dosage is 5 percent of the mass of the catalyst carrier) to obtain a catalyst precursor, drying the precursor at 250 ℃ for 5 hours, heating to 500 ℃ at 4 ℃/min, and roasting at constant temperature for 4.0 hours to obtain the required catalyst. The catalyst MoO₃11.2 percent of NiO and 2.9 percent of NiO; the specific surface area is 140m²Per g, pore volume of 0.88 ml.g^-1(ii) a The pore diameter can be as small as 20.7 nm.

The preparation method of the hydrogenation catalyst II comprises the following steps: the carrier II contains MoO₃And saturating and dipping the mixed solution of the active component of NiO and glycol (the dosage is 8 percent of the mass of the catalyst carrier) to obtain a catalyst precursor, drying the precursor at 150 ℃ for 3.0h, heating to 450 ℃ at the speed of 10 ℃/min, and roasting at constant temperature for 2.0h to obtain the required catalyst. The catalyst MoO₃20.0 percent and 3.7 percent of NiO; the specific surface area is 150m²Per g, pore volume of 0.80ml g^-1(ii) a The aperture of the glass can be 11.9 nm.

The preparation method of the hydrogenation catalyst III comprises the following steps: the carrier III is treated with a solution containing MoO₃And saturating and dipping the mixed solution of the active component of NiO and glycol (the dosage is 10 percent of the mass of the catalyst carrier) to obtain a catalyst precursor, drying the precursor at 170 ℃ for 2.0h, heating to 480 ℃ at 8 ℃/min, and roasting at constant temperature for 2.5h to obtain the required catalyst. The catalyst MoO₃24.8 percent and 5.7 percent of NiO; the specific surface area is 190m²Per g, pore volume of 0.55ml g^-1(ii) a The pore diameter can be 7.9 nm.

Filling a hydrogenation catalyst I, a hydrogenation catalyst II and a hydrogenation catalyst III into a vulcanization reactor from top to bottom according to a proportion, introducing vulcanized oil into the vulcanization reactor, and wetting a catalyst bed layer; then adjusting the temperature of the bed layer to 160 ℃, and injecting a vulcanizing agent; after hydrogen sulfide penetrates through the catalyst bed layer, raising the temperature of the catalyst bed layer to 230 ℃ at a speed of 10 ℃/h, and keeping the temperature for 8 hours; the temperature of the catalyst bed is increased to 340 ℃ at a speed of 15 ℃/h, and the temperature is kept constant for 8 hours. The average number of layers of active photo crystals of the hydrogenation catalyst I is 4.0, and the average length of the photo crystals is 5.5 nm; the average number of layers of active photo crystals of the hydrogenation catalyst II is 4.5, and the average length of the photo crystals is 5.8 nm; the average number of layers of active photo crystals of the hydrogenation catalyst III is 5.2, and the average length of the photo crystals is 5.3 nm.

Comparative example 3

the preparation method of the hydrogenation catalyst I comprises the following steps: the carrier I is added with a carrier containing MoO₃And saturating and dipping the mixed solution of the active component of NiO and tetraethyleneglycol (the dosage is 15 percent of the mass of the catalyst carrier) to obtain a catalyst precursor, drying the precursor at 150 ℃ for 5 hours, heating to 500 ℃ at 4 ℃/min, and roasting at constant temperature for 4.0 hours to obtain the required catalyst. The catalyst MoO₃11.5 percent of NiO and 2.8 percent of NiO; the specific surface area is 120m²Per g, pore volume of 0.89ml g^-1(ii) a The pore diameter can be as small as 20.8 nm.

The preparation method of the hydrogenation catalyst II comprises the following steps: the carrier II contains MoO₃Saturating and dipping the mixed solution of the active component of NiO and tetraethyleneglycol (the dosage is 18 percent of the mass of the catalyst carrier) to obtain a catalyst precursor, drying the precursor at 140 ℃ for 3.0h, heating to 450 ℃ at 10 ℃/min, and keeping the temperature constantThe required catalyst is obtained after 2.0h of calcination. The catalyst MoO₃20.5 percent of NiO and 3.8 percent of NiO; the specific surface area is 165m²Per g, pore volume of 0.87 ml.g^-1(ii) a The aperture of the glass can be 11.7 nm.

The preparation method of the hydrogenation catalyst III comprises the following steps: the carrier III is treated with a solution containing MoO₃And saturating and dipping the mixed solution of the active component of NiO and tetraethyleneglycol (the dosage is 20 percent of the mass of the catalyst carrier) to obtain a catalyst precursor, drying the precursor at 120 ℃ for 2.0h, heating to 480 ℃ at 8 ℃/min, and roasting at constant temperature for 2.5h to obtain the required catalyst. The catalyst MoO₃25.8 percent of NiO and 5.5 percent of NiO; the specific surface area is 195m²Per g, pore volume of 0.54ml g^-1(ii) a The pore diameter can be 7.7 nm.

Filling a hydrogenation catalyst I, a hydrogenation catalyst II and a hydrogenation catalyst III into a vulcanization reactor from top to bottom according to a proportion, introducing vulcanized oil into the vulcanization reactor, and wetting a catalyst bed layer; then adjusting the temperature of the bed layer to 160 ℃, and injecting a vulcanizing agent; after hydrogen sulfide penetrates through the catalyst bed layer, raising the temperature of the catalyst bed layer to 200 ℃ at a speed of 12 ℃/h, and keeping the temperature for 4 hours; the catalyst bed temperature was raised to 320 ℃ at 18 ℃/h and held constant for 4 hours. The average number of layers of active photo crystals of the hydrogenation catalyst I is 2.5, and the average length of the photo crystals is 8.8 nm; the average number of layers of active photo crystals of the hydrogenation catalyst II is 2.8, and the average length of the photo crystals is 8.7 nm; the average number of layers of active photo crystals of the hydrogenation catalyst III is 3.0, and the average length of the photo crystals is 8.3 nm.

Example 6

This example is a comparative test of the activity of the catalyst assemblies of examples 1, 2, 3, 4, 5 and comparative examples 1, 2, 3 on a 100ml fixed bed small scale hydrogenation unit. The feeding mode is as follows: the upper feeding mode. The properties of the stock oils were evaluated as shown in Table 1; the evaluation conditions are shown in Table 2; the catalyst assembly scheme is shown in table 3; the catalyst combination scheme evaluation results are shown in table 4; the results of the 2000h stability test for the catalyst combination scheme are shown in table 5.

TABLE 1 Properties of the stock oils

Table 2 evaluation of the Process conditions

TABLE 3 catalyst combination system grading scheme

TABLE 4 catalyst combination evaluation results

TABLE 52000 h catalyst combination stability test results

As can be seen from the activity stability evaluation results in tables 4 and 5, the catalyst combination scheme of the invention can significantly improve the desulfurization, denitrification and aromatic hydrocarbon saturation performance of the catalyst system, and has better stability.

Example 7

This example is a comparative test of the activity of the catalyst assemblies of examples 1, 2, 3, 4, 5 and comparative examples 1, 2, 3 on a 100ml fixed bed small scale hydrogenation unit. The feeding mode is as follows: the upper feeding mode. The properties of the stock oils were evaluated as shown in Table 6; the evaluation conditions are shown in Table 7; the catalyst assembly scheme is shown in Table 8; the results of the catalyst combination schemes are shown in Table 9.

TABLE 6 Properties of the feed oils

Table 7 evaluation of Process conditions

TABLE 8 catalyst combination system grading scheme

TABLE 9 evaluation results of catalyst combinations

As can be seen from the activity evaluation results in Table 9, the catalyst combination scheme of the present invention can significantly improve the desulfurization, denitrification and aromatic saturation performance of the catalyst system.

Claims

1. A heavy oil hydrotreating method is characterized by comprising the following contents: the heavy oil raw material enters a hydrogenation reactor, contacts with a hydrogenation catalyst bed layer to carry out hydrogenation reaction, and a reaction product flows out of the reactor; the hydrogenation catalyst bed layer is filled with a vulcanized hydrogenation catalyst I, II and a III 3 stage in sequence along the material flow direction; wherein the properties of the hydrogenation catalyst I in a sulfurized state are as follows: the aluminum oxide catalyst comprises an aluminum oxide carrier and active metals, wherein the active metals are selected from one or more of VIII group and/or VIB group metal elements; based on the weight of the catalyst, the active metal is calculated by oxide, the VIII group metal is 1wt% -9 wt%, and the VIB group metal is 5wt% -25 wt%; the average number of layers of the active photo is 7.0-9.0, and the average length of the plate crystal is 1.0-3.0 nm; the aperture is not less than 15 nm; the properties of the sulfurized hydrogenation catalyst II are as follows: the aluminum oxide catalyst comprises an aluminum oxide carrier and active metals, wherein the active metals are selected from one or more of VIII group and/or VIB group metal elements; based on the weight of the catalyst, the active metal is calculated by oxide, the VIII group metal is 1wt% -9 wt%, and the VIB group metal is 5wt% -25 wt%; the average number of layers of the active photo is 4.0-6.0, and the average length of the plate crystal is 4.0-6.0 nm; the aperture of the filter can be 10-15 nm; the properties of the hydrogenation catalyst III in a sulfurized state are as follows: the aluminum oxide catalyst comprises an aluminum oxide carrier and active metals, wherein the active metals are selected from one or more of VIII group and/or VIB group metal elements; based on the weight of the catalyst, the active metal is calculated by oxide, the VIII group metal is 1wt% -9 wt%, and the VIB group metal is 5wt% -25 wt%; the average number of layers of the active photo is 1.0-3.0, and the average length of the plate crystal is 7.0-9.0 nm; the aperture of the filter can be 5.0-9.0 nm; the metal active phase is active metal sulfide of the catalyst; the vulcanized hydrogenation catalyst is obtained by vulcanizing the oxidation state hydrogenation catalyst.

2. The method of claim 1, wherein: the oxidation state hydrogenation catalyst takes alumina or modified alumina as a carrier, VIII group and/or VIB group metal elements as active components, and the active metals are calculated by oxides based on the weight of the catalyst, wherein the VIII group metal accounts for 1-9 wt%, and the VIB group metal accounts for 5-25 wt%.

3. The method of claim 2, wherein: the oxidation state hydrogenation catalyst has the following properties: specific surface area of 100 to 250m²A pore volume of 0.3 to 1.0 mL/g^-1The pore diameter is not less than 5 nm.

4. The method of claim 1, wherein: based on the total volume of the catalyst in the reactor, the filling proportion of each level is at least 10 percent, and the sum of the filling proportions of the levels is 100 percent.

5. The method of claim 1, wherein: the preparation method of the vulcanized hydrogenation catalyst I comprises the following steps: filling an oxidation state catalyst I into a vulcanization reactor, introducing vulcanized oil into the vulcanization reactor, and wetting a catalyst bed layer; then adjusting the temperature of the bed layer to 150-170 ℃, and injecting a vulcanizing agent; after hydrogen sulfide penetrates through the catalyst bed layer, raising the temperature of the catalyst bed layer to 250-270 ℃ at the speed of 2-5 ℃/h, and keeping the temperature for 8-10 hours; and raising the temperature of the catalyst bed to 350-360 ℃ at the speed of 5-10 ℃/h, and keeping the temperature for 8-10 hours.

6. The method of claim 1, wherein: the preparation method of the vulcanized hydrogenation catalyst II comprises the following steps: filling an oxidation state hydrogenation catalyst II into a vulcanization reactor, introducing vulcanized oil into the vulcanization reactor, and wetting a catalyst bed layer; then adjusting the temperature of the bed layer to 150-170 ℃, and injecting a vulcanizing agent; after hydrogen sulfide penetrates through the catalyst bed layer, raising the temperature of the catalyst bed layer to 210-230 ℃ at a speed of 5-10 ℃/h, and keeping the temperature for 5-7 hours; and raising the temperature of the catalyst bed to 330-340 ℃ at a speed of 10-15 ℃/h, and keeping the temperature for 5-7 hours.

7. The method of claim 1, wherein: the preparation method of the vulcanized hydrogenation catalyst III comprises the following steps: filling the oxidation state catalyst into a vulcanization reactor, introducing vulcanized oil into the vulcanization reactor, and wetting a catalyst bed layer; then adjusting the temperature of the bed layer to 150-170 ℃, and injecting a vulcanizing agent; after hydrogen sulfide penetrates through the catalyst bed layer, raising the temperature of the catalyst bed layer to 180-200 ℃ at a speed of 10-15 ℃/h, and keeping the temperature for 2-4 hours; and raising the temperature of the catalyst bed to 310-320 ℃ at a speed of 15-20 ℃/h, and keeping the temperature for 2-4 hours.

8. The method of claim 1, wherein: based on the weight of all the catalysts, the proportion of the vulcanized hydrogenation catalyst I is 10-90%, the proportion of the vulcanized hydrogenation catalyst II is 10-40%, and the proportion of the vulcanized hydrogenation catalyst III is 20-80%.

9. The method of claim 1, wherein: the hydrotreating process conditions are as follows: the average reaction temperature is 330-450 ℃, the reaction hydrogen partial pressure is 8.0-20.0 MPa, and the liquid hourly volume space velocity is 0.15-3.0 h^-1The volume ratio of hydrogen to oil is 300-1500.