Hydrodenitrogenation catalyst and preparation and application thereof

Abstract

The invention discloses a hydrodenitrification catalyst as well as a preparation method and application thereof. The catalyst comprises a carrier and active components, the active components comprise Mo and Zn and / or Cu, on the basis of the total weight of the catalyst, the content of Mo is 6%-16%, the content of Zn and / or Cu is 0.5%-4.5%, and the mass ratio of Mo to S is 1.5 or above. When being used for processing a low-sulfur heavy residual oil raw material, the hydrodenitrogenation catalyst not only has good hydrodenitrogenation activity, but also has good activity stability, and is especially suitable for processing fluidized bed hydrogenation tail oil.

Description

Technical Field

[0001] The invention belongs to the technical field of heavy residue oil hydrogenation, and particularly relates to a hydrodenitrogenation catalyst and a preparation method thereof, and application in treating ebullated bed hydrogenation tail oil. Background Art

[0002] The active phase of hydrogenation catalysts currently used in the petrochemical industry is a nano-scale cluster with Mo(W)S2 as the main body and Ni or Co as the outer layer. Its characteristics are that it has high requirements for the sulfur content in the processed raw materials and the reaction atmosphere. When the sulfur content in the raw materials is low, the hydrogen sulfide in the reaction system is not enough to maintain the stable structure of the active phase, and the active phase will be reduced by hydrogen, resulting in a decrease in reaction activity.

[0003] In order to adapt to low-sulfur raw materials, researchers have proposed a variety of methods to maintain the stability of active phase sulfur.

[0004] CN1488729A discloses a process for two-stage hydrogenation and dearomatization of distillate oil. The method adopts a two-stage hydrogenation process, and both reactors use non-precious metal catalysts. A switching pipeline is set between the inlet and outlet of the two reactors. When the activity of the catalyst in the second reactor decreases, a switching operation is performed: the original second reactor is used as the first reactor, and the original first reactor is used as the second reactor. The method solves the problem of easy deactivation of the second-stage catalyst in the two-stage hydrogenation process of distillate oil with non-precious metal catalysts, and prolongs the catalyst operation cycle.

[0005] CN102465014B discloses a hydrocracking method for processing low-sulfur raw materials. The method comprises: hydrotreating high-sulfur raw materials, performing gas-liquid separation on the reaction effluent, and obtaining sulfur-containing hydrogen-rich gas; hydrocracking low-sulfur raw oil, performing gas-liquid separation on the reaction effluent, and obtaining sulfur-poor hydrogen-rich gas; mixing the sulfur-containing hydrogen-rich gas with the sulfur-poor hydrogen-rich gas, selectively performing hydrogen desulfurization treatment, and circulating back to the reactor inlet. The method effectively combines the two hydrogen-rich gases of the hydrotreating and hydrocracking processes, and fully utilizes the sulfur-containing hydrogen-rich gas from the hydrotreating to supplement sulfur for the low-sulfur raw material hydrocracking unit, effectively solving the problem of catalyst desulfurization during long-term operation of the low-sulfur hydrocracking unit.

[0006] CN105749933B discloses a method for preparing a hydrogenation catalyst. The hydrogenation catalyst includes a carrier and an active metal component loaded on the carrier, wherein the active metal component is distributed in a double layer along the radial direction of the carrier, the active metal component of the core layer is NiO and WO3, and the active metal component of the shell layer is MoO3 and NiO and / or CoO, and the method comprises the following steps: immersing the hydrothermally treated carrier in an acidic solution containing a molybdenum compound and a nickel compound and / or a cobalt compound and drying to obtain a carrier; immersing the above-mentioned carrier in an alkaline solution containing a nickel compound and a tungsten compound, and then drying and calcining to obtain a catalyst. The catalyst utilizes the layered distribution of the active metal component on the carrier to improve the hydrodesulfurization, carbon removal and denitrification activity of the catalyst, but for processing low-sulfur raw materials, it still has the disadvantage of poor stability. Summary of the invention

[0007] In view of the shortcomings of the prior art, in order to improve the stability of the hydrogenation catalyst used in a low-sulfur environment, the present invention proposes a heavy oil hydrodenitrogenation catalyst and its preparation method and application. When the heavy oil hydrodenitrogenation catalyst of the present invention is used to process low-sulfur heavy residual oil raw materials, it not only has good hydrodenitrogenation activity, but also has good activity stability, and is particularly suitable for processing ebullating bed hydrogenation tail oil.

[0008] The first aspect of the present invention provides a hydrodenitrogenation catalyst, comprising a carrier and an active component, wherein the active component comprises Mo and Zn and / or Cu, and based on the total weight of the catalyst, the content of Mo is 6%-16%, the content of Zn and / or Cu is 0.5%-4.5%, and the mass ratio of Mo to S is above 1.5.

[0009] Furthermore, the content of Zn and / or Cu refers to the total content of Zn and Cu. If Zn is contained alone but Cu is not contained, it refers to the content of Zn, and if Cu is contained alone but not Zn, it refers to the content of Cu.

[0010] Furthermore, the hydrodenitrogenation catalyst comprises a carrier, an active component and an S element, and the active component is Mo and Zn and / or Cu.

[0011] In the prior art, the S content in the sulfurized hydrodenitrogenation catalyst is generally above 10 wt %, while the active component of the present invention adopts Mo in combination with Zn and / or Cu, and controls the S content in the catalyst at a relatively low level, which is beneficial to improving the hydrodenitrogenation ability of the catalyst and preventing the loss of sulfur in the active phase in a low-sulfur reaction environment.

[0012] Furthermore, in the hydrodenitrogenation catalyst, the mass ratio of Mo to S is preferably 1.5-3.0, and more preferably 1.6-2.4. In the prior art, the mass ratio of Mo to S is generally less than 1.5, and is generally between 1-1.3. The inventors have found through research that the use of the catalyst of the present invention, especially when the mass ratio of Mo to S is above 1.5, can improve the hydrodenitrogenation ability of the catalyst and prevent the loss of sulfur in the active phase in a low-sulfur reaction environment.

[0013] Furthermore, based on the weight of the catalyst, the content of the carrier is 75%-92%, preferably 75%-91%, and the content of Mo, S and Zn and / or Cu is 8%-25%, preferably 9%-25%.

[0014] Further, according to XPS test, in the catalyst, Mo includes +2-valent Mo, 0-valent Mo and +4-valent Mo, wherein +2-valent Mo accounts for 50%-70% of the total Mo in terms of atoms, 0-valent Mo accounts for 10%-30% of the total Mo in terms of atoms, and +4-valent Mo accounts for 1%-25% of the total Mo in terms of atoms; preferably, +2-valent Mo accounts for 50%-65% of the total Mo in terms of atoms, 0-valent Mo accounts for 15%-27% of the total Mo in terms of atoms, and +4-valent Mo accounts for 8%-25% of the total Mo in terms of atoms. The inventors of the present invention have found through research that by controlling the ratio of Mo in different valence states in the metal active phase, especially when +2-valent Mo and 0-valent Mo are present in the catalyst in a specific ratio, it is more conducive to making Mo cooperate with Zn and / or Cu and S to form a metal active phase, and it is more conducive to preventing the loss of sulfur in the active phase in a low-sulfur reaction environment.

[0015] Furthermore, the sum of +4-valent Mo, +2-valent Mo and 0-valent Mo accounts for more than 90% of the total Mo in terms of atoms, preferably 90%-99%. In addition to +2-valent Mo, 0-valent Mo and +4-valent Mo, the catalyst provided by the present invention may also contain +5-valent or +6-valent Mo.

[0016] Furthermore, the present invention has no particular limitation on the carrier, and may be various carriers conventionally used in the art, may be commercially available products, or may be prepared by any method in the prior art. For example, the carrier may be an inorganic refractory oxide. Preferably, the carrier is one or more of alumina, silicon oxide, and amorphous silicon aluminum. Considering the cost and effect comprehensively, the carrier is preferably alumina. The carrier may contain one or more of modifying elements such as phosphorus, silicon, boron, fluorine, magnesium, and sodium. The amount of the modifying element added is a conventional amount, preferably accounting for 0.2%-3.0% of the carrier mass.

[0017] Furthermore, the carrier properties are as follows: specific surface area is 230-400m 2 / g, preferably 250-360m 2 / g, pore volume is 0.4-1.1cm 3 / g, preferably 0.6-1.0cm 3 / g.

[0018] The second aspect of the present invention provides a method for preparing the above catalyst, comprising:

[0019] (1) introducing molybdenum hexacarbonyl and an organic compound containing Zn and / or Cu into a carrier by an impregnation method to obtain a catalyst precursor I;

[0020] (2) contacting the catalyst precursor I with a dispersant in the presence of an inert gas to obtain a catalyst precursor II;

[0021] (3) At least one of step (3-1) or step (3-2) is adopted, wherein:

[0022] Step (3-1) comprises sulfiding the catalyst precursor II, wherein the sulfidation is performed so that in the obtained hydrodenitrogenation catalyst, the mass ratio of Mo to S is greater than 1.5, preferably 1.5-3.0, and more preferably 1.6-2.4, based on the total weight of the catalyst;

[0023] Step (3-2) comprises impregnating the catalyst precursor II with an impregnation solution containing a polysulfide compound, and then drying it.

[0024] Furthermore, in step (1), there is no particular limitation on the impregnation method, and it can be an equal volume impregnation or an excess impregnation. In the present invention, the molybdenum hexacarbonyl and the organic compound containing Zn and / or Cu can be simultaneously introduced into the carrier by co-impregnation, or they can be separately introduced into the carrier by step-by-step impregnation, and there is no particular limitation on the order of their introduction. When the organic compound containing Zn and / or Cu includes two or more, they can also be simultaneously introduced into the carrier by co-impregnation, or they can be separately introduced into the carrier by step-by-step impregnation. According to the present invention, it is preferred that the molybdenum hexacarbonyl and the organic compound containing Zn and / or Cu are introduced by co-impregnation.

[0025] Further, step (1) preferably comprises: impregnating the support with an impregnation solution containing molybdenum hexacarbonyl and an organic compound containing Zn and / or Cu, and then drying; preferably, the impregnation is an equal volume impregnation method or an excess impregnation method. The drying conditions can be selected in a wide range, as long as the solvent can be removed without evaporating the molybdenum hexacarbonyl and the organic compound containing Zn and / or Cu.

[0026] Furthermore, in step (1), preferably, the drying is reduced pressure vacuum drying, and further preferably, the drying conditions include: drying temperature of 60-120°C, preferably 80-100°C, drying vacuum degree of 0.1-2torr, preferably 0.2-1torr, and drying time of 1-10 hours, preferably 2-8 hours.

[0027] Further, in step (1), the solvent in the impregnation solution is preferably one or more of ethanol, benzene, toluene, xylene, ethylbenzene, and tetralin, and more preferably at least one of toluene, xylene, ethylbenzene, and tetralin, and optionally ethanol. Preferably, the organic zinc compound is selected from one or more of zinc propionate, zinc octoate, zinc p-toluenesulfonate, and zinc fumarate. The organic copper compound is selected from at least one of copper propionate, copper naphthenate, copper citrate, copper acetylacetonate, and copper lactate.

[0028] Furthermore, in the impregnation solution of step (1), the concentration of molybdenum hexacarbonyl is 0.2-2.5 mol / L, preferably 0.3-2.0 mol / L.

[0029] Furthermore, in the impregnation solution of step (1), the concentration of the organic zinc compound and / or organic copper compound is 0.02-0.9 mol / L, preferably 0.05-0.8 mol / L. The concentration of the organic zinc compound and / or organic copper compound is the sum of the concentrations of the organic zinc compound and the organic copper compound in the impregnation solution.

[0030] Furthermore, in step (1), the carrier is a conventional residue hydrodenitrogenation catalyst carrier, which can be selected from one or more of alumina, silicon oxide, and amorphous silicon aluminum. The properties of the carrier are as follows: the specific surface area is 230-400m 2 / g, preferably 250-360m 2 / g, pore volume is 0.4-1.1cm 3 / g, preferably 0.6-1.0cm 3 / g. The carrier may be doped with one or more of the modifying elements such as phosphorus, silicon, boron, fluorine, magnesium, sodium, etc. The amount of the modifying element added is a conventional amount, preferably accounting for 0.2%-3.0% of the carrier mass.

[0031] Further, the amount of the carrier, molybdenum hexacarbonyl and the organic zinc compound and / or organic copper compound is such that the prepared hydrodenitrogenation catalyst has a Mo content of 6%-16% and a Zn and / or Cu content of 0.5%-4.5% based on the total weight of the catalyst. Those skilled in the art can appropriately select the amount and concentration of the impregnation solution based on the above disclosure.

[0032] Furthermore, in step (2), the inert gas is preferably one or more of nitrogen, argon, helium and neon.

[0033] Furthermore, in step (2), the dispersant is contacted with the catalyst precursor I to obtain an organic molybdenum dimer with good stability, which is more conducive to the subsequent formation of a highly dispersed active phase. There is no particular limitation on the manner in which the dispersant is contacted with the catalyst precursor I, and it can be carried out continuously or intermittently. The dispersant can be introduced in a gaseous form or in a liquid form, and the present invention has no particular limitation on this.

[0034] Furthermore, in step (2), the type of the dispersant is selected from a wide range, as long as it can be in contact with the catalyst precursor I to obtain an organic molybdenum dimer with good stability. Preferably, the dispersant is selected from at least one of acetic acid, acetic anhydride, citric acid, dimethyl malonate, malonic acid and succinic acid; further preferably, the dispersant is acetic acid and / or acetic anhydride.

[0035] Furthermore, preferably, in step (2), the amount of the dispersant used is 1 to 10 g, preferably 2 to 5 g, relative to 1 g of the catalyst precursor I.

[0036] Further, preferably, the contacting conditions in step (2) include: a pressure of 0 to 1 MPa, preferably 0.1 to 0.5 MPa, a temperature of 80 to 180° C., preferably 100 to 150° C., and a time of 8 to 36 hours, preferably 12 to 24 hours. The pressure is gauge pressure.

[0037] Further, preferably, the method further comprises removing the remaining dispersant by evaporative drying, preferably by reduced pressure vacuum drying, after the contacting in step (2). The drying conditions can be selected in a wide range, so as to remove the solvent without causing a large amount of loss of the loaded organic molybdenum species, organic zinc metal compound and / or organic copper metal compound from the surface of the carrier. Preferably, the evaporative drying conditions include: a drying temperature of 80 to 150° C., preferably 100 to 120° C., a drying vacuum of 0.1 to 2 torr, preferably 0.2 to 1 torr, and a drying time of 1 to 8 hours, preferably 2 to 6 hours.

[0038] Furthermore, the contacting in step (2) can be carried out in a reaction vessel such as an autoclave, preferably under closed conditions.

[0039] Furthermore, the dispersant and the catalyst precursor I are placed in a reaction kettle, sealed, an inert gas is introduced to a contact pressure, heated to a contact temperature, and the temperature is maintained. The method also includes drying the catalyst precursor obtained in step (2) under reduced pressure and vacuum after cooling.

[0040] Further, there is no particular limitation on the sulfurization in step (3-1), and it can be carried out by conventional methods in the art. A known sulfurization method can be used, and preferably the sulfurization includes dry sulfurization and / or wet sulfurization. The dry sulfurization and wet sulfurization described in the present invention have conventional definitions in the art. There is no particular limitation on the conditions of dry sulfurization and wet sulfurization, so long as the mass ratio of Mo to S in the hydrogenation catalyst is above 1.5 (preferably 1.5 to 3.0, more preferably 1.6 to 2.4).

[0041] Furthermore, it is preferred to treat the catalyst precursor II using step (3-2), which is more conducive to obtaining a catalyst with better hydrogenation processing ability.

[0042] Furthermore, the specific implementation of the impregnation in step (3-2) can be as described above, and the present invention will not be repeated here. Preferably, the impregnation in step (3-2) is an equal volume impregnation.

[0043] Furthermore, in step (3), the solvent in the impregnation solution containing polysulfide compounds is at least one of C5-C10 alkanes and / or cycloalkanes and aromatic hydrocarbons, preferably one or more of cyclohexane, n-heptane, n-octane, tetralin, decalin, toluene and xylene.

[0044] Furthermore, in step (3), the polysulfide compound refers to a compound containing at least 2 moles of sulfur in 1 mole, for example 2-3 moles. The polysulfide compound is preferably one or more of di-tert-butyl polysulfide (the amount of sulfur is preferably 2-3), tert-nonyl polysulfide (the amount of sulfur is preferably 2-3), tert-dodecyl polysulfide (the amount of sulfur is preferably 2-3), and dihexyl disulfide.

[0045] Furthermore, the di-tert-butyl polysulfide includes but is not limited to di-tert-butyl disulfide and di-tert-butyl trisulfide.

[0046] Furthermore, the tert-nonyl polysulfide includes but is not limited to tert-nonyl disulfide and tert-nonyl trisulfide.

[0047] Furthermore, the tert-dodecyl polysulfide includes but is not limited to tert-dodecyl trisulfide and tert-dodecyl disulfide.

[0048] Furthermore, the dihexyl disulfide includes but is not limited to n-dihexyl disulfide and tert-dihexyl disulfide.

[0049] Furthermore, in the impregnation solution containing polysulfide compounds, the mass concentration of polysulfide compounds is 2%-20%, preferably 3%-15%.

[0050] Further, preferably, the amounts of the impregnation solution containing polysulfide compounds and the catalyst precursor II are such that the mass ratio of Mo to S in the prepared hydrogenation catalyst is above 1.5, preferably 1.5 to 3.0, and more preferably 1.6 to 2.4.

[0051] Furthermore, in step (3-2), preferably, the method further comprises drying after the impregnation. Preferably, the drying is reduced pressure vacuum drying, and further preferably, the drying conditions include: a drying temperature of 60-120°C, preferably 80-100°C, a vacuum degree of 0.1-2.0 torr, preferably 0.2-1.0 torr, and a drying time of 1-6 hours, preferably 2-4 hours.

[0052] Furthermore, the material obtained by drying in step (3-2) can be directly used as a product, and before the product is used, it can be treated with hydrogen. The material obtained by drying in step (3-2) can also be treated with hydrogen and then used directly. It is understood that the methods before and after hydrogen treatment and the obtained products are all within the scope of protection of the present invention.

[0053] Furthermore, preferably, step (3-2) further comprises subjecting the dried material to hydrogen treatment.

[0054] Further, preferably, in step (3-2), the hydrogen treatment is carried out under a hydrogen atmosphere, and the hydrogen atmosphere is provided by a hydrogen-containing gas.

[0055] Further, preferably, the hydrogen-containing gas contains hydrogen and an inert gas. The selection range of the type of the inert gas is as described above, and the present invention will not be repeated here.

[0056] Further, preferably, the hydrogen content in the hydrogen-containing gas is not less than 50v%, preferably 50-100v%, and more preferably 100v%.

[0057] Further, preferably, during the hydrogen treatment process, the hydrogen is passed once. More preferably, relative to 1g of the dried material, the amount of hydrogen used is 0.1 to 1NL, preferably 0.2 to 0.8NL.

[0058] Furthermore, the hydrogen treatment is carried out under closed conditions, for example, in a reactor.

[0059] Further, preferably, the conditions of the hydrogen treatment include: the hydrogen treatment temperature is 180 to 300° C., preferably 200 to 260° C., and the treatment time is 2 to 10 hours, preferably 3 to 6 hours.

[0060] Furthermore, after the hydrogen treatment in step (3-2), the process may also include cooling, inert gas replacement and the like.

[0061] The third aspect of the present invention provides the use of the above catalyst in the hydrodenitrogenation reaction of a low-sulfur heavy feedstock.

[0062] Furthermore, the low-sulfur heavy feedstock is at least one of ebullated bed hydrogenation tail oil, coal tar and Fischer-Tropsch synthesis oil, more preferably ebullated bed hydrogenation tail oil. The density of the low-sulfur heavy feedstock is 0.95-1.05 g / cm 3 The mass content of sulfur is below 8000ppm, and may be 1500-7000ppm. The mass content of nitrogen is below 5000ppm, and may be 500-5000ppm. The mass content of residual carbon is 8% to 25%.

[0063] Furthermore, the hydrodenitrogenation reaction conditions are as follows: reaction temperature is 300-450°C, reaction pressure is 12-25MPa, hydrogen-to-oil volume ratio is 500-2000:1, liquid hourly volume space velocity is 0.1-0.5h -1 .

[0064] Compared with the prior art, the present invention has the following advantages:

[0065] 1. In conventional hydrogenation catalysts, active metals are usually Mo and Ni(Co), wherein the active phase is mainly MoS2 (+4 valent Mo), and Ni(Co) is distributed around MoS2. The inventors of the present invention have found through research that by controlling the ratio of Mo in different valence states in the metal active phase, especially the presence of +2 valent Mo and 0 valent Mo in the catalyst in a specific proportion, so that Mo cooperates with Zn and / or Cu and S to form a metal active phase, Mo and sulfur are more closely combined, and the interaction force between Zn and / or Cu and sulfur is also stronger, thereby preventing the loss of sulfur in the active phase in a low-sulfur reaction environment. Moreover, by regulating the electron distribution of the main crystal plane of the metal active phase by Zn and / or Cu, the orbital energy level of the main crystal plane is reduced, so that its ability to hydrogenolyze nitrides is selectively enhanced, and when used to treat high-nitrogen raw materials, it has better denitrification activity. Therefore, when the catalyst of the present invention is used to treat low-sulfur and high-nitrogen raw materials, it has better denitrification activity and stability.

[0066] 2. In the preparation method of the catalyst of the present invention, zinc and / or copper and molybdenum species are introduced into the catalyst using low-valent organic molybdenum and organic zinc source and / or organic copper source, so that molybdenum and zinc and / or copper are evenly mixed on the catalyst surface. The dispersant is preferably acetic acid and / or acetic anhydride to process the molybdenum source, and tetraacetic acid dimolybdenum monomer is obtained. This monomer molybdenum is connected with molybdenum by Mo-Mo chemical bonds. Compared with conventional oxide molybdenum species, tetraacetic acid dimolybdenum monomer has a smaller distance between molybdenum atoms and a reduced coordination number, which is conducive to generating low-valent sulfide molybdenum species in the sulfurization process. Finally, polysulfide is used as a sulfur source to process tetraacetic acid dimolybdenum monomer. Since the content of sulfur is limited and the valence of molybdenum is relatively low, and there is an electron-donating effect of zinc, the valence of molybdenum in the obtained catalyst is mainly based on 0 valence and +2 valence.

[0067] 3. The method provided by the present invention is particularly suitable for hydrotreating ebullated bed hydrogenation tail oil. Since ebullated bed hydrogenation tail oil is different from straight-run residual oil, it is residual oil after ebullated bed hydrogenation treatment. Although it has the characteristics of low sulfur, nitrogen and aromatic hydrocarbon content, the nitrogen atoms in the remaining nitrides are often protected by more condensed aromatic rings, making it more difficult to approach and remove the catalyst active center, and its hydrodegradation difficulty is further increased. When the hydrotreating method of the present invention is used to treat ebullated bed hydrogenation tail oil, it can ensure that the hydrodecarbonization and hydrodenitrogenation activities are fully exerted in a low-sulfur environment, and on the other hand, it is more conducive to improving the stability of the hydrotreating. DETAILED DESCRIPTION

[0068] The present invention is further described below in conjunction with the examples, but it should be understood that the protection scope of the present invention is not limited by the examples. In the present invention, unless otherwise clearly stated, percentages and percentage contents are all based on mass.

[0069] In the present invention, the content of Mo, Zn and / or Cu, and S in the hydrodenitrogenation catalyst can be measured by ICP, and the equipment used is an OPTIMA7000DV atomic emission spectrometer produced by PE. 0.1g of sample is dissolved in a mixed solution with a volume ratio of 3HCl:1HNO3:0.5HF, and then the mixed solution is diluted with deionized water to a certain volume so that the content of the element to be measured in the solution is between 1-10ppm, and then the measurement is performed.

[0070] In the present invention, the operating conditions of XPS are: light source: Mg Kα, energy step: 0.05 eV, scanning range: 200-250 eV (molybdenum), 280-300 eV (carbon). When analyzing the valence state of molybdenum, it is considered that the molybdenum species with a 3d5 / 2 orbital binding energy of 227-228 eV is a 0-valence molybdenum species, the molybdenum species with a 3d5 / 2 orbital binding energy of 228-229 eV is a +2-valence molybdenum species, the molybdenum species with a 3d5 / 2 orbital binding energy of 229-231 eV is a +4-valence molybdenum species, and the molybdenum species with a 3d5 / 2 orbital binding energy greater than 231 eV is a +5 or +6-valence molybdenum.

[0071] The carriers used in the following examples and comparative examples of the present invention are prepared by the following method:

[0072] Weigh 1000.0g of alumina dry powder, add 20.0g of succinic acid and 10.0g of sesbania powder, mix well, add 1000.0g of aqueous solution containing 3.0% nitric acid, roll for 10.0min, and extrude strips using a clover plate with a diameter of 1.8mm. Dry at 140℃ for 4.0h and then roast at 550℃ for 4.0h. The carrier that is roasted and shaped to a length of 3-5mm is recorded as S-0. The properties of the carrier are as follows: the specific surface area is 315m 2 / g, pore volume is 0.82cm 3 / g.

[0073] Example 1

[0074] 20.0 g of molybdenum hexacarbonyl and 7.3 g of zinc octoate were mixed with 120 g of toluene to prepare solution MQ-1.

[0075] Take 100.0 g of S-0, impregnate it with MQ-1, and then dry it under reduced pressure. The drying temperature is 100° C., the vacuum degree is 0.5 torr, and the drying time is 6.0 hours. The obtained catalyst precursor is recorded as P-1.

[0076] Put P-1 into an autoclave and add 300.0g of acetic acid. After sealing, introduce 0.2MPa nitrogen and heat to 100°C for 24 hours. After cooling, dry the catalyst under reduced pressure at 110°C, with a vacuum degree of 0.3torr and a drying time of 4.0 hours. The obtained catalyst precursor is recorded as Y-1.

[0077] 10 g of di-tert-butyl tripolysulfide and 80.0 g of toluene were mixed to prepare solution SQ-1. Y-1 was impregnated with SQ-1, and then the catalyst was dried under reduced pressure at a drying temperature of 90°C, a vacuum degree of 0.3 torr, and a drying time of 4.0 hours. The obtained catalyst precursor was recorded as SY-1.

[0078] 50.0 g of SY-1 was loaded into a reactor, and 30.0 NL of hydrogen was introduced under closed conditions. The reaction temperature was controlled at 200° C. The reaction was carried out for 4.0 hours. After cooling, the atmosphere was replaced with nitrogen. The obtained catalyst was recorded as Cat-1.

[0079] Example 2

[0080] 30.0 g of molybdenum hexacarbonyl and 15.0 g of zinc propionate were mixed with 120 g of xylene to prepare solution MQ-2.

[0081] Take 100.0 g of S-0, impregnate it with MQ-2, and then dry it under reduced pressure. The drying temperature is 110° C., the vacuum degree is 0.3 torr, and the drying time is 5.0 hours. The obtained catalyst precursor is recorded as P-2.

[0082] Put P-2 into an autoclave and add 240.0g of acetic acid. After sealing, introduce 0.3MPa nitrogen and heat to 120°C. Keep the temperature constant for 24 hours. After cooling, dry the catalyst under reduced pressure at 110°C, vacuum degree of 0.2torr and drying time of 4.0 hours. The obtained catalyst precursor is recorded as Y-2.

[0083] 10g of tert-nonyl trisulfide and 80.0g of tetralin were prepared into solution SQ-2. Y-2 was impregnated with SQ-2, and then the catalyst was dried under reduced pressure at a drying temperature of 100°C, a vacuum degree of 0.2 torr, and a drying time of 4.0 hours. The obtained catalyst precursor was recorded as SY-2.

[0084] 50.0 g of SY-2 was loaded into a reactor, and 35.0 NL of hydrogen was introduced under closed conditions. The reaction temperature was controlled at 220° C. The reaction was carried out for 4.0 hours. After cooling, the reaction was replaced with nitrogen. The obtained catalyst was recorded as Cat-2.

[0085] Example 3

[0086] 40.0 g of molybdenum hexacarbonyl and 20.0 g of zinc lactate were prepared with 120 g of ethylbenzene to prepare solution MQ-3.

[0087] Take 100.0 g of S-0, impregnate it with MQ-3, and then dry it under reduced pressure. The drying temperature is 120° C., the vacuum degree is 0.2 torr, and the drying time is 6.0 hours. The obtained catalyst precursor is recorded as P-3.

[0088] Put P-3 into an autoclave and add 260.0g of acetic acid. After sealing, introduce -0.4MPa nitrogen. Heat to 110°C and keep the temperature constant for 30 hours. After cooling, dry the catalyst under reduced pressure at 120°C, with a vacuum degree of 0.2 torr and a drying time of 6.0 hours. The obtained catalyst precursor is recorded as Y-3.

[0089] 10 g of tert-dodecyl tripolysulfide and 80.0 g of decahydronaphthalene were mixed to prepare solution SQ-3. Y-3 was impregnated with SQ-3, and then the catalyst was dried under reduced pressure at a drying temperature of 110°C, a vacuum degree of 0.2 torr, and a drying time of 6.0 hours. The obtained catalyst precursor was recorded as SY-3.

[0090] 50.0 g of SY-3 was loaded into a reactor, and 25.0 NL of hydrogen was introduced under closed conditions. The reaction temperature was controlled at 240°C and the reaction was carried out for 3.0 hours. After cooling, the reaction was replaced with nitrogen. The obtained catalyst was recorded as Cat-3.

[0091] Example 4

[0092] 50.0 g of molybdenum hexacarbonyl and 15.0 g of zinc fumarate were mixed with 120 g of tetralin to prepare solution MQ-4.

[0093] Take 100.0 g of S-0, impregnate it with MQ-4, and then dry it under reduced pressure. The drying temperature is 110° C., the vacuum degree is 0.2 torr, and the drying time is 4.0 hours. The obtained catalyst precursor is recorded as P-4.

[0094] Put P-4 into an autoclave and add 280.0g of acetic acid. After sealing, introduce 0.4MPa nitrogen and heat to 120°C. Keep the temperature constant for 32 hours. After cooling, dry the catalyst under reduced pressure at 120°C, vacuum degree of 0.2torr and drying time of 5.0 hours. The obtained catalyst precursor is recorded as Y-4.

[0095] 10 g of tert-dihexyl disulfide and 80.0 g of tetralin were mixed to prepare solution SQ-4. Y-4 was impregnated with SQ-4, and then the catalyst was dried under reduced pressure at a drying temperature of 120°C, a vacuum degree of 0.2 torr, and a drying time of 6.0 hours. The obtained catalyst precursor was recorded as SY-4.

[0096] 50.0 g of SY-4 was loaded into a reactor, and 20.0 NL of hydrogen was introduced under closed conditions. The reaction temperature was controlled at 230° C. The reaction was carried out for 6.0 hours. After cooling, the reaction was replaced with nitrogen. The obtained catalyst was recorded as Cat-4.

[0097] Example 5

[0098] 30.0 g of molybdenum hexacarbonyl and 15.0 g of copper propionate were mixed with 120 g of xylene to prepare solution MQ-5.

[0099] Take 100.0 g of S-0, impregnate it with MQ-5, and then dry it under reduced pressure. The drying temperature is 120° C., the vacuum degree is 0.3 torr, and the drying time is 5.0 hours. The obtained catalyst precursor is recorded as P-5.

[0100] Put P-5 into an autoclave and add 240.0g of acetic acid. After sealing, introduce 0.3MPa nitrogen and heat to 120°C. Keep the temperature constant for 24 hours. After cooling, dry the catalyst under reduced pressure at 110°C, vacuum degree of 0.2torr and drying time of 4.0 hours. The obtained catalyst precursor is recorded as Y-5.

[0101] 10g of tert-nonyl trisulfide and 80.0g of tetralin were prepared into solution SQ-5. Y-5 was impregnated with SQ-5, and then the catalyst was dried under reduced pressure at a drying temperature of 100°C, a vacuum degree of 0.2 torr, and a drying time of 4.0 hours. The obtained catalyst precursor was recorded as SY-5.

[0102] 50.0 g of SY-5 was loaded into a reactor, and 35.0 NL of hydrogen was introduced under closed conditions. The reaction temperature was controlled at 220° C. The reaction was carried out for 4.0 hours. After cooling, the gas was replaced with nitrogen. The obtained catalyst was recorded as Cat-5.

[0103] Example 6

[0104] 40.0 g of molybdenum hexacarbonyl and 20.0 g of copper lactate were prepared with 120 g of ethylbenzene to prepare solution MQ-6.

[0105] Take 100.0 g of S-0, impregnate it with MQ-6, and then dry it under reduced pressure. The drying temperature is 120° C., the vacuum degree is 0.2 torr, and the drying time is 6.0 hours. The obtained catalyst precursor is recorded as P-6.

[0106] Put P-6 into an autoclave and add 230.0g of acetic anhydride. After sealing, introduce -0.4MPa nitrogen. Heat to 110°C and keep the temperature constant for 30 hours. After cooling, dry the catalyst under reduced pressure at 120°C, vacuum degree of 0.2torr, and drying time of 6.0 hours. The obtained catalyst precursor is recorded as Y-6.

[0107] 10 g of tert-dodecyl tripolysulfide and 80.0 g of decahydronaphthalene were mixed to prepare solution SQ-6. Y-6 was impregnated with SQ-6, and then the catalyst was dried under reduced pressure at a drying temperature of 110°C, a vacuum degree of 0.2 torr, and a drying time of 6.0 hours. The obtained catalyst precursor was recorded as SY-6.

[0108] 50.0 g of SY-6 was loaded into a reactor, and 25.0 NL of hydrogen was introduced under closed conditions. The reaction temperature was controlled at 240° C. The reaction was carried out for 3.0 hours. After cooling, the gas was replaced with nitrogen. The obtained catalyst was recorded as Cat-6.

[0109] Comparative Example 1

[0110] Take 30.0 g of ammonium molybdate and 25.0 g of zinc nitrate hexahydrate and prepare 120 mL of aqueous solution, which is recorded as DQ-1.

[0111] 100.0 g of S-0 was impregnated with DQ-1, evaporated at 120°C for 5.0 hours, and calcined at 500°C for 5.0 hours. The resulting catalyst was named DCT-1.

[0112] 1000.0 g of cyclohexane and 50.0 g of DMDS were prepared into a sulfiding liquid and recorded as DSQ-1.

[0113] 10.0g of DCT-1 was loaded into a reaction tube, and hydrogen and DSQ-1 were introduced for sulfurization. The sulfurization temperature was 340°C, the sulfurization time was 8.0 hours, the hydrogen pressure during sulfurization was 5.0MPa, the hydrogen flow rate was 150ml / L, and the DSQ-1 flow rate was 20.0ml / h. The catalyst after sulfurization was recorded as DCT-S1.

[0114] Comparative Example 2

[0115] Take 30.0 g of ammonium molybdate and 20.0 g of nickel nitrate hexahydrate to prepare 100 mL of aqueous solution, which is recorded as DQ-2.

[0116] 100.0 g of S-0 was impregnated with DQ-2, evaporated at 120°C for 5.0 hours, and calcined at 500°C for 5.0 hours. The resulting catalyst was named DCT-2.

[0117] 1000.0 g of cyclohexane and 50.0 g of DMDS were prepared into a sulfiding liquid and recorded as DSQ-2.

[0118] 10.0g of DCT-2 was loaded into a reaction tube, and hydrogen and DSQ-2 were introduced for sulfurization. The sulfurization temperature was 340°C, the sulfurization time was 8.0 hours, the hydrogen pressure during sulfurization was 5.0MPa, the hydrogen flow rate was 150ml / L, and the DSQ-2 flow rate was 20.0ml / h. The catalyst after sulfurization was recorded as DCT-S2.

[0119] Comparative Example 3

[0120] The preparation methods of catalyst precursor P-3 and sulfur-containing solution SQ-3 are the same as those in Example 3.

[0121] P-3 was impregnated with SQ-3, and then the catalyst was dried under reduced pressure at a drying temperature of 110°C, a vacuum degree of 0.2 torr, and a drying time of 6.0 hours. The obtained catalyst precursor was recorded as DSP-3.

[0122] 50.0 g of DSP-3 was loaded into a reactor, and 25.0 NL of hydrogen was introduced under closed conditions. The reaction temperature was controlled at 240° C. and the reaction was carried out for 3.0 hours. After cooling, the gas was replaced with nitrogen. The obtained catalyst was recorded as DCT-3.

[0123] Comparative Example 4

[0124] Take 30.0 g of ammonium molybdate and 25.0 g of copper nitrate hexahydrate and prepare 120 mL of aqueous solution, which is recorded as DQ-4.

[0125] 100.0 g of S-0 was impregnated with DQ-4, evaporated at 120°C for 5.0 hours, and calcined at 500°C for 5.0 hours. The resulting catalyst was named DCT-4.

[0126] 1000.0 g of cyclohexane and 50.0 g of DMDS were prepared into a sulfiding liquid and recorded as DSQ-4.

[0127] 10.0g of DCT-4 was loaded into a reaction tube, and hydrogen and DSQ-4 were introduced for sulfurization. The sulfurization temperature was 340°C, the sulfurization time was 8.0 hours, the hydrogen pressure during sulfurization was 5.0MPa, the hydrogen flow rate was 150ml / L, and the DSQ-4 flow rate was 20.0ml / h. The catalyst after sulfurization was recorded as DCT-S4.

[0128] Table 1 Elemental analysis of the catalysts obtained in each example

[0129]

[0130]

[0131] Table 2 Valence analysis results of Mo in the catalysts obtained in each example

[0132] Catalyst No. 0 price Mo ratio / % +2-valent Mo proportion / % +4-valent Mo proportion / % Cat-1 19.0 61.3 12.4 Cat-2 20.1 57.6 18.3 Cat-3 18.6 62.7 15.1 Cat-4 20.5 62.9 10.8 Cat-5 19.4 59.8 16.8 Cat-6 21.1 60.2 15.7 DCT-S1 ＜1 1.3 79.4 DCT-S2 ＜1 2.4 77.9 DCT-3 5.9 36.7 55.0 DCT-S4 ＜1 1.1 74.3

[0133] Examples 7-12

[0134] The oil produced by hydrogenation of ebullated bed residue oil was selected as the raw material, and the fixed bed hydrogenation process was adopted to carry out hydrogenation evaluation experiments on the catalysts obtained in the above Examples 1-6. The properties of the oil produced by hydrogenation of ebullated bed residue oil are shown in Table 3.

[0135] Table 3 Properties of oil produced by boiling bed residue hydrogenation

[0136]

[0137]

[0138] A hydrogenation protective agent (FZC-100B) and a hydrodemetallization catalyst (FZC-204A) were loaded before the above catalyst, and the loading volume ratio of the protective agent, the hydrodemetallization catalyst, and the catalyst obtained in the example was 1:2:4. The operating conditions were: reaction temperature 390°C, reaction pressure 20.0MPa, hydrogen-oil volume ratio 1500:1, liquid hourly volume space velocity 0.4h -1 After 1500 hours of reaction evaluation, the residual carbon value and nitrogen content in the fraction of hydrogenation oil not less than 300°C were analyzed, and the results are shown in Table 4.

[0139] Comparative Examples 5-8

[0140] The oil produced by hydrogenation of ebullated bed residue oil (see Table 3) was selected as the raw material, and the fixed bed process was used to evaluate the activity of the catalysts obtained in Comparative Examples 1-4. Hydrogenation protective agent (FZC-100B) and hydrodemetallization catalyst (FZC-204A) were loaded before the above catalysts, and the loading volume ratio of the protective agent, hydrodemetallization catalyst, and catalyst obtained in the comparative example was 1:2:4. The operating conditions were: reaction temperature 390°C, reaction pressure 20.0MPa, hydrogen-oil volume ratio 1500:1, liquid hourly volume space velocity 0.4h -1 After 1500 hours of reaction evaluation, the residual carbon value and nitrogen content in the fraction of hydrogenation oil not less than 300°C were analyzed, and the results are shown in Table 4.

[0141] Table 4 Properties of fixed bed hydrogenation oil

[0142]

[0143]

[0144] It can be seen from the evaluation results in Table 4 that the catalyst of the present invention has good hydrodenitrogenation and hydrodecarbonization activities and good stability when it is used to generate oil by deep processing of low-sulfur ebullated bed residue oil by hydrogenation.

Claims

1. A hydrodenitrogenation catalyst comprising a carrier and an active component, wherein the active component comprises Mo and Zn and / or Cu, wherein the content of Mo is 6%-16%, the content of Zn and / or Cu is 0.5%-4.5% based on the total weight of the catalyst, and the mass ratio of Mo to S is above 1.5, preferably 1.5-3.0, and more preferably 1.6-2.

4.

2. The catalyst according to claim 1, characterized in that In the catalyst, Mo includes +2-valent Mo, 0-valent Mo and +4-valent Mo, wherein +2-valent Mo accounts for 50%-70% of the total Mo by atom, 0-valent Mo accounts for 10%-30% of the total Mo by atom, and +4-valent Mo accounts for 1%-25% of the total Mo by atom; preferably, +2-valent Mo accounts for 50%-65% of the total Mo by atom, 0-valent Mo accounts for 15%-27% of the total Mo by atom, and +4-valent Mo accounts for 8%-25% of the total Mo by atom.

3. The catalyst according to claim 2, characterized in that The sum of +4-valent Mo, +2-valent Mo and 0-valent Mo accounts for more than 90% of the total Mo in terms of atoms, preferably 90% to 99%.

4. The catalyst according to claim 1, characterized in that The carrier is one or more of aluminum oxide, silicon oxide, and amorphous silicon aluminum; optionally, the carrier contains one or more of modifying elements among phosphorus, silicon, boron, fluorine, magnesium, and sodium. Preferably, the modifying elements account for 0.2%-3.0% of the carrier mass.

5. The catalyst according to claim 1, characterized in that Based on the weight of the catalyst, the content of the carrier is 75%-92%, and the content of Mo, S and Zn and / or Cu is 8%-25%.

6. The catalyst according to claim 1 or 4, characterized in that The properties of the carrier are as follows: specific surface area is 230-400m 2 / g, preferably 250-360m 2 / g, pore volume is 0.4-1.1cm 3 / g, preferably 0.6-1.0cm 3 / g.

7. A method for preparing the catalyst according to any one of claims 1 to 6, comprising: (1) introducing molybdenum hexacarbonyl and an organic compound containing Zn and / or Cu into a carrier by an impregnation method to obtain a catalyst precursor I; (2) contacting the catalyst precursor I with a dispersant in the presence of an inert gas to obtain a catalyst precursor II; (3) At least one of step (3-1) or step (3-2) is adopted, wherein: Step (3-1) comprises sulfiding the catalyst precursor II, wherein the sulfidation is performed so that in the obtained hydrodenitrogenation catalyst, the mass ratio of Mo to S is greater than 1.5, preferably 1.5-3.0, and more preferably 1.6-2.4, based on the total weight of the catalyst; Step (3-2) comprises impregnating the catalyst precursor II with an impregnation solution containing a polysulfide compound, and then drying it.

8. The method according to claim 7, characterized in that In step (1), the carrier is impregnated with an impregnation solution containing molybdenum hexacarbonyl and an organic compound containing Zn and / or Cu, and then dried; preferably, the impregnation is an equal volume impregnation method or an excess impregnation method; Preferably, the solvent in the impregnation solution is one or more of ethanol, benzene, toluene, xylene, ethylbenzene, and tetralin, more preferably at least one of toluene, xylene, ethylbenzene, and tetralin, and optionally ethanol; Preferably, the organic zinc compound is selected from one or more of zinc propionate, zinc octoate, zinc lactate and zinc fumarate; Preferably, the organic copper compound is selected from at least one of copper propionate, copper naphthenate, copper citrate, copper acetylacetonate and copper lactate.

9. The method according to claim 8, characterized in that In the impregnation solution of step (1), the concentration of molybdenum hexacarbonyl is 0.2-2.5 mol / L, preferably 0.3-2.0 mol / L, and the concentration of the organic zinc compound and / or organic copper compound is 0.02-0.9 mol / L, preferably 0.05-0.8 mol / L.

10. The method according to claim 8, characterized in that In step (1), the drying method is reduced pressure vacuum drying, wherein the drying temperature is 60-120° C., preferably 80-100° C., the vacuum degree during drying is 0.1-2.0 torr, preferably 0.2-1.0 torr, and the drying time is 1-10 hours, preferably 2-8 hours.

11. The method according to claim 7, characterized in that In step (2), the dispersant is selected from at least one of acetic acid, acetic anhydride, citric acid, dimethyl malonate, malonic acid and succinic acid, preferably acetic acid and / or acetic anhydride; And / or, in step (2), the amount of the dispersant is 1 to 10 g, preferably 2 to 5 g, relative to 1 g of the catalyst precursor I; And / or, the contacting conditions in step (2) include: a pressure of 0-1.0 MPa, preferably 0.1-0.5 MPa, a temperature of 80-180° C., preferably 100-150° C., and a time of 8-36 hours, preferably 12-24 hours; Optionally, after the contacting in step (2), the remaining dispersant is removed by evaporative drying, preferably by reduced pressure vacuum drying. Preferably, the conditions of the evaporative drying include: a drying temperature of 80 to 150° C., preferably 100 to 120° C., a drying vacuum degree of 0.1 torr, preferably 0.2 torr, and a drying time of 1 to 8 hours, preferably 2 to 6 hours.

12. The method according to claim 7, characterized in that In step (3-2), in the impregnation solution containing polysulfide compounds, the solvent is at least one of C5-C10 alkanes and / or cycloalkanes and aromatic hydrocarbons, preferably one or more of cyclohexane, n-heptane, n-octane, tetralin, decalin, toluene, and xylene; and / or, the polysulfide compound is one or more of di-tert-butyl polysulfide (the amount of sulfur is preferably 2-3), tert-nonyl polysulfide (the amount of sulfur is preferably 2-3), tert-dodecyl polysulfide (the amount of sulfur is preferably 2-3), and dihexyl disulfide; preferably, in the impregnation solution containing polysulfide compounds, the mass concentration of polysulfide compounds is 2%-20%, preferably 3%-15%.

13. The method according to claim 7, characterized in that In step (3-2), the impregnation method is equal volume impregnation; preferably, the impregnation in step (3) is followed by drying, and the drying method is vacuum reduced pressure drying, wherein the drying temperature is 60-120°C, preferably 80-100°C, the vacuum degree during drying is 0.1-2.0 torr, preferably 0.2-1.0 torr, and the drying time is 1-6 hours, preferably 2-4 hours.

14. The method according to claim 13, characterized in that The material dried in step (3-2) is treated with hydrogen, and the hydrogen is introduced once. The amount of hydrogen is 0.1 to 1NL, preferably 0.2 to 0.8NL, relative to 1g of the dried material. The hydrogen treatment is carried out under closed conditions. Preferably, the hydrogen treatment temperature is 180-300°C, preferably 200-260°C, and the treatment time is 2.0-10.0 hours, preferably 3.0-6.0 hours.

15. Use of the catalyst according to any one of claims 1 to 6 in the hydrodenitrogenation reaction of low-sulfur heavy feedstock.

16. The use according to claim 15, characterized in that The low-sulfur heavy raw material is at least one of ebullated bed hydrogenation tail oil, coal tar and Fischer-Tropsch synthesis oil, more preferably ebullated bed hydrogenation tail oil; preferably, the density of the low-sulfur heavy raw material is 0.95-1.05 g / cm 3 , the mass content of sulfur is less than 8000ppm, the mass content of nitrogen is 500-5000ppm, and the mass content of residual carbon is 8% to 25%.

17. The use according to claim 15, characterized in that: The hydrodenitrogenation reaction conditions are as follows: reaction temperature is 300-450°C, reaction pressure is 12-25MPa, hydrogen-to-oil volume ratio is 500-2000:1, liquid hourly volume space velocity is 0.1-0.5h -1 .

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