CN116020497A

CN116020497A - Composite carrier, hydrogenation catalyst, and preparation method and application thereof

Info

Publication number: CN116020497A
Application number: CN202111255042.6A
Authority: CN
Inventors: 贾燕子; 曾双亲; 户安鹏; 胡大为; 赵新强; 王轶凡; 邓中活
Original assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Current assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Priority date: 2021-10-27
Filing date: 2021-10-27
Publication date: 2023-04-28

Abstract

The invention discloses a composite carrier, a hydrogenation catalyst containing the composite carrier and a hydrogenation treatment method, wherein the composite carrier comprises pseudo-boehmite containing phosphorus and magnesium and solid acid, and the pseudo-boehmite containing phosphorus and magnesium is roasted for 3 hours at 600 DEG CThe obtained alumina containing phosphorus and magnesium has a bimodal pore structure, the bimodal pore structure is measured by mercury intrusion method, and the pore distribution is positioned at a mesopore volume V of 3-100nm _{Middle hole} 0.7-1.7mL/g, a macropore pore volume V with a pore distribution of 100-5000nm _{Macropores are formed} 1.7-4.7mL/g, total pore volume V _{Total (S)} 2.4-6.4mL/g. The hydrogenation catalyst is applied to the hydrocarbon oil hydrogenation reaction, has more excellent hydrodesulfurization and denitrification activities and aromatic hydrocarbon hydrogenation activities, and is obviously superior to the prior art.

Description

Composite carrier, hydrogenation catalyst, and preparation method and application thereof

Technical Field

The invention relates to the field of hydrogenation catalysts, in particular to a composite carrier, a catalyst containing the carrier and application of the catalyst in hydrocarbon oil hydrogenation reaction.

Background

The hydrogenation catalyst is the core of a perhydro refinery and contact of hydrocarbon oil feedstock with the catalyst may occur including: hydrodesulfurization, hydrodenitrogenation, hydrodemetallization, hydrocracking, and the like. Wherein the performance of the catalyst plays a key role in the modification effect of hydrocarbon raw materials and the selectivity of target products.

Since the catalyst support acts to provide a path for the diffusion of reactants and products during the catalytic reaction and to provide attachment sites for the formation of the reactive phase, the pore structure characteristics of the support surface are closely related to the catalyst performance. Alumina, especially gamma-alumina, has relatively high pore structure, specific surface area and heat stability, and solid acid has porous and acidic features and is used as carrier for preparing catalyst. The precursor of alumina is hydrated alumina, such as pseudo-boehmite, and the particle size, morphology, crystallinity, impurity crystal content and the like of the alumina carrier have influence on the properties of pore volume, pore distribution, specific surface area and the like. In the prior art, alumina carriers meeting specific requirements can be obtained by modulating the properties of particle size, morphology, crystallinity and the like of hydrated alumina. In the prior art, a great number of hydrogenation catalysts and preparation methods are disclosed, and a great number of reports are also provided on the influence of carrier characteristics on the catalyst performance, including the influence of pore diameter, pore distribution, acidity, auxiliaries and the like on the final catalyst performance, but in the scheme in the prior art, the alumina carrier with large mesopore volume, large macropore volume and total pore volume is difficult to obtain, and the corresponding hydrogenation catalyst cannot be obtained.

Disclosure of Invention

The invention aims to further improve the performance of a hydrogenation catalyst, provides a composite carrier formed by compositing pseudo-boehmite containing phosphorus and magnesium with specific pore characteristics and solid acid, and also provides a hydrogenation catalyst containing the composite carrier, wherein the hydrogenation catalyst has good hydrogenation activity.

In the prior art, pseudo-boehmite with large mesopore volume and macropore volume and total pore volume is difficult to obtain, the inventor of the present invention found in research that pseudo-boehmite with a bimodal pore structure can be obtained by adding a phosphorus-containing compound and a magnesium-containing compound in proper steps in the preparation process and controlling the reaction conditions, and an alumina carrier obtained by calcining the pseudo-boehmite at 600 ℃ for 3 hours has a bimodal pore structure, wherein the bimodal pore structure is measured by a mercury intrusion method, and the pore distribution is positioned at a mesopore pore volume V of 3-100nm _{Middle hole} 0.7-1.7mL/g, a macropore pore volume V with a pore distribution of 100-5000nm _{Macropores are formed} 1.7-4.7mL/g, total pore volume V _{Total (S)} 2.4-6.4mL/g; preferably, the pore distribution is located at a pore volume V of 3-100nm _{Middle hole} 0.9-1.5mL/g, pore distribution at a pore volume V of 100-5000nm _{Macropores are formed} 1.8-3.2mL/g, and the total pore volume V is 2.7-4.7mL/g; further preferably, the pore distribution is located at a pore volume V of 3-100nm _{Middle hole} 0.9-1.4mL/g, pore distribution at a pore volume V of 100-5000nm _{Macropores are formed} 1.8-2.5mL/g and a total pore volume V of 2.7-3.9mL/g. The composite carrier formed by pseudo-boehmite containing phosphorus and magnesium and solid acid is used as a carrier to prepare the hydrogenation catalyst, and the roasting step in the catalyst preparation process is controlled, so that the activity and the activity stability of the finally obtained hydrogenation catalyst are obviously improved compared with the prior art. Specifically, the invention mainly comprises the following contents:

the invention providesA composite carrier comprising phosphorus and magnesium containing pseudo-boehmite and a solid acid, wherein the phosphorus and magnesium containing pseudo-boehmite has a bimodal pore structure as measured by mercury intrusion method, and the pore distribution is at a mesopore volume V of 3-100nm _{Middle hole} 0.7-1.7mL/g, a macropore pore volume V with a pore distribution of 100-5000nm _{Macropores are formed} 1.7-4.7mL/g, total pore volume V _{Total (S)} 2.4-6.4mL/g.

The invention also provides a preparation method of the composite carrier, which comprises the following steps:

(1) Contacting phosphorus-containing compound, magnesium-containing compound and inorganic aluminum-containing compound solution with acid or alkali to perform precipitation reaction, or contacting organic aluminum-containing compound with magnesium-containing compound and phosphorus-containing compound solution to perform hydrolysis reaction to obtain hydrated alumina containing phosphorus and magnesium;

(2) Aging the obtained hydrated alumina containing phosphorus and magnesium under the condition that the pH value is 7-10.5, mixing the aged solid product with solid acid according to a certain proportion, molding and drying to obtain the composite carrier;

the precipitation reaction or the hydrolysis reaction in step (1) is carried out at a pH of 4 to 7.

Further, the invention provides a hydrogenation catalyst containing the composite carrier, which comprises the composite carrier and a hydrogenation active metal component loaded on the composite carrier, wherein the hydrogenation active metal component contains at least one VIB group metal component and at least one VIII group metal component, the content of the carrier is 30-99 wt% based on the total catalyst, the content of the VIB group metal component is 0.5-50 wt% based on oxide, and the content of the VIII group metal component is 0.5-20 wt%.

The invention also provides a preparation method of the hydrogenation catalyst, which comprises the steps of loading hydrogenation active metal components on the composite carrier or the composite carrier prepared by the method, and then drying and roasting to obtain the hydrogenation catalyst.

Finally, the invention also provides the application of the hydrogenation catalyst or the hydrogenation catalyst prepared by the preparation method in the hydrogenation reaction of hydrocarbon oil.

The hydrogenation catalyst provided by the invention is applied to hydrocarbon oil hydrogenation reaction, has more excellent hydrogenation activity, and has significantly better aromatic hydrocarbon hydrogenation performance, desulfurization performance and denitrification performance than the prior art under the same conditions.

Detailed Description

The endpoints and any values of the ranges disclosed herein are not limited to the precise range or value, and are understood to encompass values approaching those ranges or values. For numerical ranges, one or more new numerical ranges may be found between the endpoints of each range, between the endpoint of each range and the individual point value, and between the individual point value, in combination with each other, and are to be considered as specifically disclosed herein.

In the present invention, the pore distribution refers to a distribution of pore diameters unless otherwise specified. The pore diameter refers to the pore diameter. The term "dry weight" as used herein refers to the weight of the dry matter obtained after drying at 600℃for 3 hours, unless otherwise specified.

First, according to the composite carrier provided by the present invention, the content of the solid acid is not particularly required, and may be adjusted conventionally according to practical use, for example, the content of the solid acid may be 1 to 99 parts by weight, preferably 5 to 80 parts by weight, based on the total dry basis of the composite carrier.

The solid acid has wide optional range, is generally a common molecular sieve, and can be zeolite with a macroporous structure, such as at least one of faujasite, beta zeolite and omega zeolite; can also be zeolite with a medium pore structure, such as at least one of mordenite, ZSM-5 zeolite, ZSM-11 zeolite, ZSM-22 zeolite, ZSM-23 zeolite, ZSM-35 zeolite, ZSM-48 zeolite, and ZSM-57 zeolite; also can be zeolite with small pore structure, such as zeolite with Erionite zeolite and/or ZSM-34 zeolite structure; preferably, the molecular sieve is selected from at least one of faujasites, beta zeolites, omega type zeolites, mordenite, ZSM-5 zeolites, ZSM-11 zeolites, ZSM-22 zeolites, ZSM-23 zeolites, ZSM-35 zeolites, ZSM-48 zeolites, ZSM-57 zeolites, erionite zeolites and ZSM-34 zeolites. According to the present invention, preferably, the solid acid is selected from at least one of faujasite, beta zeolite, ZSM-5 zeolite, mordenite and silica-alumina. The silica-alumina is preferably a silica-alumina having a pseudo-boehmite structure, which may be commercially available or prepared using any of the prior art techniques. Further preferably, the faujasite is a Y-type zeolite, more preferably at least one of an HY-type zeolite, a phosphorus-type Y-zeolite REY, a phosphorus-type HY-zeolite REY, an ultrastable Y-zeolite USY, a partially amorphized USY, a phosphorus-type ultrastable Y-zeolite REUSY, a titanium-containing Y-zeolite, a phosphorus-containing Y and ultrastable and HY-type zeolite, and a dealuminated Y-type zeolite.

For the pseudo-boehmite containing phosphorus and magnesium in the composite carrier, the pore distribution of the alumina containing phosphorus and magnesium obtained after roasting at 600 ℃ for 3 hours is preferably located at a mesopore pore volume V of 3-100nm _{Middle hole} 0.9-1.5mL/g, a macropore pore volume V with a pore distribution of 100-5000nm _{Macropores are formed} 1.8-3.2mL/g, total pore volume V _{Total (S)} 2.7-4.7mL/g.

Various assistants for improving the performance of the carrier and the catalyst can be further contained in the pseudo-boehmite containing phosphorus and magnesium, for example, metal assistant elements and/or nonmetal assistant elements are further contained in the pseudo-boehmite containing phosphorus and magnesium; the metal auxiliary element is at least one of lithium, sodium, potassium, rubidium, cesium, francium, beryllium, calcium, zirconium and titanium; the nonmetallic auxiliary agent element is at least one selected from boron element, fluorine element and silicon element; preferably, al is based on the total amount of pseudo-boehmite dry basis containing phosphorus and magnesium ₂ O ₃ The content of (2) is 84 to 99.8 wt%, more preferably 84 to 99.7 wt%; p (P) ₂ O ₅ The content of (C) is 0.1-6 wt.%, the content of MgO is 0.1-5 wt.%, and the content of the auxiliary element is 0-5 wt.%, more preferably 0.1-5 wt.%.

Secondly, the invention provides a method for preparing the composite carrier, according to the preparation method, in order to obtain pseudo-boehmite and the composite carrier with better pore structure characteristics, the reaction conditions can be further optimized, for example, the precipitation reaction in the step (1) or the hydrolysis reaction can be carried out under the condition of pH of 4-6.5; the temperatures of the precipitation reaction and the hydrolysis reaction are each independently 30-90 ℃; in the present invention, the conditions for the precipitation reaction are selected in a wide range, and preferably, the conditions for the precipitation reaction include: the reaction temperature is 40-90 ℃, preferably 45-80 ℃, and the reaction time is 10-60 minutes, preferably 10-30 minutes. The conditions for the hydrolysis reaction are not particularly limited in the present invention, as long as water is brought into contact with the organic aluminum-containing compound to cause hydrolysis reaction to produce hydrated alumina. The conditions of the hydrolysis reaction may include: the reaction temperature is 40-90 ℃, preferably 45-80 ℃, and the reaction time is 2-30 hours, preferably 2-20 hours;

the inorganic aluminum-containing compound is aluminum salt and/or aluminate; the organic aluminum-containing compound is at least one of aluminum alkoxides which can generate hydrated aluminum oxide precipitation through hydrolysis reaction with water; the phosphorus-containing compound is at least one selected from phosphoric acid, ammonium phosphate, ammonium hydrogen phosphate, diammonium hydrogen phosphate, sodium phosphate and potassium phosphate; the magnesium-containing compound is one or more selected from magnesium chloride, magnesium nitrate, magnesium sulfate and magnesium acetate; the acid is at least one of sulfuric acid, hydrochloric acid, nitric acid, carbonic acid, phosphoric acid, formic acid, acetic acid, citric acid and oxalic acid; the alkali is at least one of sodium metaaluminate, potassium metaaluminate, sodium hydroxide, potassium hydroxide and ammonia water.

According to the method provided by the invention, the ageing of step (2) is preferably carried out at a pH of 8-10; the aging conditions include: the temperature is 50-95deg.C, preferably 55-90deg.C; the time is 0.5-8 hours, preferably 2-6 hours; the drying conditions in step (2) include: the temperature is 50-350deg.C, preferably 80-250deg.C, and the drying time is 1-12 hr, preferably 2-8 hr.

When the composite carrier contains additive elements capable of improving performance, the precipitation reaction or the hydrolysis reaction in the step (1) also comprises adding optional additiveA compound of agent elements, the auxiliary elements comprising metallic auxiliary elements and/or non-metallic auxiliary elements; the metal auxiliary element is at least one of lithium, sodium, potassium, rubidium, cesium, francium, beryllium, calcium, zirconium and titanium, more preferably at least one of lithium, sodium, potassium, beryllium, calcium, zirconium and titanium; the nonmetallic auxiliary agent element is at least one selected from boron element, fluorine element and silicon element; the content of each component is such that Al is based on the total amount of the alumina containing phosphorus and magnesium in the obtained alumina containing phosphorus and magnesium ₂ O ₃ The content of P is 85-99.8 wt%, more preferably 85-99.7 wt% ₂ O ₅ The content of (2) is 0.1-5 wt.%, the content of MgO is 0.1-5 wt.%, the content of auxiliary elements is 0-5 wt.%, more preferably 0.1-5 wt.%.

According to the present invention, the composite support is preferably prepared without a calcination step.

The invention also provides a hydrogenation catalyst containing the composite carrier, the metal types and the content in the catalyst are not particularly required, the catalyst is determined according to specific application, preferably, the VIB group metal component is Mo and/or W, and the VIII group metal component is Co and/or Ni; the catalyst comprises 40-94 wt.% of a support, 5-45 wt.% of a group VIB metal component and 1-15 wt.% of a group VIII metal component, calculated as oxides, based on the total amount of the catalyst.

Hydrogen programmed temperature reduction method (H) ₂ TPR) measurement is mainly characterized by the interaction force between metal and support, according to the present invention, a hydrogenation catalyst is provided, preferably by hydrogen temperature programmed reduction (H ₂ -TPR) peak height P of the low temperature reduction peak at 300-500 DEG C _{Low temperature peak} Peak height P with high temperature reduction peak at 650-850 deg.c _{High temperature peak} Ratio s=p of (2) _{Low temperature peak} /P _{High temperature peak} 0.5-2.0; more preferably, the peak height P of the low temperature reduction peak _{Low temperature peak} Peak height P from high temperature reduction peak _{High temperature peak} Ratio s=p of (2) _{Low temperature peak} /P _{High temperature peak} From 0.7 to 1.9, preferably from 0.8 to 1.8.

In order to obtain the hydrogenation catalyst, the invention also provides a corresponding preparation method, which mainly comprises the steps of preparing a composite carrier, loading a hydrogenation active metal component on the composite carrier, drying and roasting, and the like.

The type and amount of the hydrogenation active metal component are not particularly limited, and the active metal component and the amount thereof which are conventional in the art can be adopted, and can be the active metal component and the amount which are commonly used in the art for hydrocarbon oil hydrogenation catalysts; preferably, the active metal component is selected from a group VIB metal component and/or a group VIII metal component. The present invention is not particularly limited with respect to the group VIB metal component, which is preferably Mo and/or W, and the group VIII metal component, which is preferably Co and/or Ni.

The invention has wider selection range for the dosage of the composite carrier, the VIB group metal component and the VIII group metal component; preferably, the composite carrier is present in an amount of from 30 to 99 wt.%, calculated as oxides, of from 0.5 to 50 wt.% of the group VIB metal component and from 0.5 to 20 wt.% of the group VIII metal component, based on the total amount of the hydrogenation catalyst.

Further preferably, the composite support comprises 40 to 94 wt.% of the total amount of the hydrogenation catalyst, 5 to 45 wt.% of the group VIB metal component, and 1 to 15 wt.% of the group VIII metal component, calculated as oxides. More preferably, the composite support comprises 76 to 90 wt.%, calculated as oxides, of the group VIB metal component and 8 to 18 wt.%, calculated as oxides, of the group VIII metal component, based on the total amount of the hydrogenation catalyst.

The method for preparing the hydrogenation catalyst is not particularly limited, and the hydrogenation active metal component may be supported on a composite carrier by any method known in the art, for example, kneading, dry mixing or dipping; preferably, the method of supporting the hydrogenation-active metal component on a phosphorus-containing alumina comprises impregnating the phosphorus-containing alumina with an impregnating solution comprising at least one group VIB metal compound and at least one group VIII metal compound, followed by drying and calcination.

According to the invention, further, the group VIB metal compound and the group VIII metal compound are each independently selected from at least one of their soluble compounds (including the corresponding metal compounds that are soluble in water in the presence of a co-solvent). Specifically, the group VIB metal compound, for example, molybdenum, may be selected from salts and/or oxides of molybdenum-containing metals, for example, may be selected from at least one of molybdenum oxide, molybdate, para-molybdate, phosphomolybdate, preferably at least one of molybdenum oxide, ammonium molybdate, ammonium paramolybdate, phosphomolybdic acid; the group VIII metal compound, for example cobalt, may be selected from at least one of cobalt nitrate, cobalt acetate, basic cobalt carbonate, cobalt chloride, preferably cobalt nitrate and/or basic cobalt carbonate, for example nickel, may be selected from at least one of nickel-containing salts, oxides and hydroxides, for example may be selected from at least one of nickel nitrate, chloride, formate, acetate, phosphate, citrate, oxalate, carbonate, basic carbonate, hydroxide, phosphide, sulfide, aluminate, molybdate and oxide, preferably at least one of nickel oxalate, carbonate, basic carbonate, hydroxide, phosphate and oxide, more preferably at least one of nickel nitrate, nickel acetate, basic nickel carbonate, nickel chloride and nickel carbonate.

According to the invention, the invention may also contain organic additives during the catalyst preparation, such as during the preparation of the soluble compounds of the group VIB metal compounds and the group VIII metal compounds. The manner of introducing the organic additive is not particularly limited in the present invention, and the organic additive may be introduced in any manner, for example, may be introduced together with the group VIII metal, may be introduced together with the group VIB metal element, may be introduced after the group VIII and/or group VIB metal element is introduced, and may be introduced before the group VIII and/or group VIB element is introduced. The kind of the organic additive is not particularly limited in the present invention, and the organic additive is at least one selected from oxygen-containing and/or nitrogen-containing organic matters selected from organic alcohols and/or organic acids, and the nitrogen-containing organic matters are at least one selected from organic amines and organic amine salts; specifically, the oxygen-containing organic matter is selected from at least one of ethylene glycol, glycerol, polyethylene glycol (with a molecular weight of 200-1500), diethylene glycol, butanediol, acetic acid, maleic acid, oxalic acid, aminotriacetic acid, 1, 2-cyclohexanediamine tetraacetic acid, citric acid, tartaric acid and malic acid, and preferably at least one of ethylene glycol, glycerol, polyethylene glycol and citric acid; the nitrogen-containing organic matter is selected from at least one of ethylenediamine, diethylenetriamine, cyclohexanediamine tetraacetic acid, glycine, nitrilotriacetic acid, EDTA and amine salts thereof, preferably EDTA and/or nitrilotriacetic acid.

Further, the method and time of the impregnation are not particularly limited, and the impregnation method may be excessive liquid impregnation, pore saturation impregnation, multiple impregnation and the like according to the amount of the impregnation liquid, and may be soaking, spray impregnation and the like according to the manner of the impregnation; the impregnation time is preferably 0.5 to 3 hours. Further, by adjusting and controlling the concentration, amount or amount of support of the impregnation liquid, a specific amount of hydrogenation catalyst can be prepared, as is well known to those skilled in the art.

In order to further improve the activity stability of the hydrogenation catalyst, preferably, the drying conditions are: the temperature is 50-350 ℃, and the drying time is 1-12 hours; the roasting conditions are as follows: the temperature is 400-1000deg.C, preferably 410-880 deg.C, more preferably 430-850 deg.C, 450-830 deg.C, the time is 1-10 hr, and the heating rate is 50-600deg.C/hr, preferably 100-550deg.C/hr. According to the present invention, the atmosphere for the firing and the drying is not particularly limited, and may be at least one of air, oxygen and nitrogen, preferably air.

Finally, the invention also provides an application of the hydrogenation catalyst or the hydrogenation catalyst prepared by any one of the preparation methods in hydrocarbon oil hydrogenation reaction.

According to the present invention, the hydrogenation catalyst may be presulfided prior to use in accordance with conventional methods in the art to convert the active metal component supported thereon to a metal sulfide component; the pre-vulcanization method can be as follows: presulfiding the hydrogenation catalyst with sulfur, hydrogen sulfide or a sulfur-containing feedstock in the presence of hydrogen at a temperature of 140-400 ℃. This pre-vulcanization may be performed ex-situ or in-situ.

The hydrogenation conditions in the application of the hydrogenation catalyst are not particularly limited, and reaction conditions common in the art can be adopted; preferably, the reaction temperature is 200-420 ℃, more preferably 220-400 ℃, the pressure is 2-18MPa, more preferably 2-16MPa, the liquid hourly space velocity is 0.1-10 hours-1, more preferably 0.15-6 hours-1, and the hydrogen-oil volume ratio is 50-5000, more preferably 50-4000.

The hydrotreating reaction apparatus in the application of the hydrotreating catalyst in the present invention is not particularly limited, and may be any reactor sufficient to allow the feedstock oil to contact the hydrotreating catalyst under hydrotreating reaction conditions, such as a fixed bed reactor, a slurry bed reactor, a moving bed reactor or an ebullated bed reactor.

The application object of the hydrogenation catalyst is not particularly limited, and the hydrogenation catalyst can be directly used for processing various hydrocarbon oil raw materials so as to carry out hydro-upgrading or hydro-cracking on the hydrocarbon oil raw materials. The hydrocarbon oil raw material may be various heavy mineral oils or synthetic oils or their mixed distillate oils, for example, may be at least one selected from crude oil, distillate oil, solvent refined oil, cerate, underfills oil, fischer-tropsch synthetic oil, coal liquefied oil, light deasphalted oil and heavy deasphalted oil; is particularly suitable for the hydrotreatment of at least one of gasoline, diesel oil, wax oil, lubricating oil, kerosene, naphtha, atmospheric residuum, vacuum residuum, petroleum wax and Fischer-Tropsch synthetic oil.

The present invention will be described in detail by examples. In the following examples, the materials involved are commercially available unless otherwise indicated.

Pore volumes in the different pore size ranges of the phosphorus and magnesium containing alumina were measured using mercury porosimetry.

H of oxidation state catalyst ₂ TPR (temperature programmed reduction) test on Autochem II 2920 multifunctional adsorption apparatus from Micromeritics Co., USAAnd (5) setting. The experimental procedure was as follows: filling 0.20g of 40-60 mesh catalyst into a U-shaped quartz tube, heating to 50 ℃ at a speed of 2 ℃/min in 50mL/min argon, pretreating a sample for 10min, and switching to be H-containing ₂ Ar carrier gas with volume fraction of 10% and gas flow rate of 50mL/min. After the base line is stabilized, the temperature is raised to 1000 ℃ at the speed of 10 ℃/min, carrier gas enters a cold trap after passing through a reactor, water generated in the reduction process is condensed, and meanwhile, a thermal conductivity cell detector is used for detecting signals, so that a TPR spectrogram of a sample is obtained.

Example 1

This example is intended to illustrate the hydrogenation catalyst provided by the present invention and a method for preparing the same.

(1) Preparation of pseudo-boehmite PA1:

in a 2L reaction tank, 5000 mL of aluminum sulfate solution with the concentration of 60 g/L, containing 40 g of magnesium nitrate, 8.0mL of 85 wt% concentrated phosphoric acid and ammonia water solution with the concentration of 6 wt% are added in parallel to carry out precipitation reaction, the reaction temperature is 50 ℃, the reaction time is 30 minutes, the flow rate of the ammonia water solution is controlled to enable the pH value of a reaction system to be 5.0, after the precipitation reaction is finished, a proper amount of ammonia water is added into slurry to enable the pH value of the slurry to be 8.7, the slurry is aged for 120 minutes at 70 ℃ and then filtered, a filter cake is pulped and washed by deionized water for 2 times, and the filter cake is dried for 24 hours at 120 ℃ to obtain PA1, the structure and the composition of the PA1 are characterized by adopting XRD, and the PA1 has a pseudo-boehmite structure. The contents of phosphorus element, magnesium element and auxiliary element in PA1 are shown in table 1. The pore structure of the resulting alumina was measured by firing PA1 at 600℃for 3 hours, and the results are shown in Table 1.

(2) Preparation of composite support Z1

100 g of PA1 and 100 g of Y-type molecular sieve (product of China petrochemical catalyst, kaolin, inc. with a dry basis content of 83%) calculated by alumina are mixed and extruded into a trilobal wet strip with an outer diameter of 1.6 mm, and the wet strip is dried at 120 ℃ for 3 hours to obtain a composite carrier Z1.

(3) Preparation of hydrogenation catalyst C1:

110 g of the composite support Z1 are taken and 80 ml of a mixed aqueous solution composed of molybdenum trioxide, basic nickel carbonate and phosphoric acid (the mixed aqueous solution contains MoO ₃ 240 g/l, 59 g/l NiO, P ₂ O ₅ 50 g/L) impregnated composite carrier Z1, the impregnation time is 4 hours, the drying is carried out at 110 ℃ for 4 hours, the heating rate is 180 ℃/h, the temperature is increased to 650 ℃ and the roasting is carried out for 3 hours, thus obtaining hydrogenation catalyst C1.

Comparative example 1

Pseudo-boehmite and catalyst were prepared as in example 1, except that only 8.0mL of 85 wt.% phosphoric acid was added to the aluminum sulfate solution, without magnesium nitrate, to give CPA1. The composition of CPA1, which was calculated by XRD characterization, is shown in Table 1, as represented by XRD characterization, using XRD characterization according to the method of example 1 for preparing composite support and catalyst, support DZ1 and comparative agent DC1, and the pore structure of alumina obtained after calcination of CPA1 at 600℃for 3 hours was measured, and the content of metal oxide in DC1 is shown in Table 2.

Comparative example 2

Pseudo-boehmite and a catalyst were prepared as in example 1, except that the aluminum sulfate solution contained no magnesium nitrate, and the flow rate of the aqueous ammonia solution was directly controlled to bring the pH of the reaction system to 8.7, and after the precipitation reaction was completed, it was not necessary to add aqueous ammonia to the slurry to adjust the pH to obtain CPA2. The composition of CPA2, as calculated by XRD characterization, is shown in Table 1, as characterized by XRD for CPA2 having a pseudo-boehmite structure. The pore structure of alumina obtained after CPA2 was calcined at 600℃for 3 hours was measured by preparing carrier DZ2 and comparative DC2 in the same manner as in example 1, and the results are shown in Table 1, and the content of metal oxide in DC2 is shown in Table 2.

Example 2

The hydrogenation catalyst was prepared by the method of example 1, except that the conditions for impregnating and drying the composite support in step (3) and then calcining were different, specifically: and (3) heating to 350 ℃ at a heating rate of 180 ℃/h, and roasting for 3 hours to obtain the hydrogenation catalyst C2. The metal oxide content of the hydrogenation catalyst is shown in table 2.

Example 3

Preparation of pseudo-boehmite PA3:

in a 2L reaction tank, 4000 mL of an alumina solution containing 85 wt% concentrated phosphoric acid and having a concentration of 45 g/L, 22.1mL of magnesium nitrate and 20g of a sodium metaaluminate solution containing 210 g/L of alumina and having a caustic coefficient of 1.58 are added in parallel to carry out precipitation reaction, the reaction temperature is 80 ℃, the flow rate of reactants is adjusted to enable the neutralization pH value to be 4.0, and the reaction residence time is 15 minutes; dilute ammonia water with the concentration of 5 weight percent is added into the obtained slurry to adjust the pH of the slurry to 9.0, the temperature is raised to 85 ℃, the aging is carried out for 3 hours, then a vacuum filter is used for filtering, and after the filtering is finished, 20 liters of deionized water (the temperature is 85 ℃) is added on a filter cake to wash the filter cake for about 30 minutes. And adding the qualified filter cake into 3 liters of deionized water, stirring to form slurry, pumping the slurry into a spray dryer for drying, controlling the outlet temperature of the spray dryer to be in the range of 100-110 ℃, and drying the material for about 2 minutes to obtain PA3. The composition of PA3, as calculated by XRD characterization, is listed in table 1, as characterized by XRD for PA3 having a pseudo-boehmite structure.

The pore structure of the alumina obtained after firing PA2 at 600℃for 3 hours was measured in the same manner as in example 1, and the results are shown in Table 1. .

Support Z3 and catalyst C3 were prepared as in example 1, except that ZSM-5 (medium petrochemical catalyst, kaolin, product, 94% by weight on a dry basis) was used as the molecular sieve, the firing rate was 150℃per hour, the firing temperature was 650℃and the metal oxide content of C3 was as shown in Table 2.

Example 4

(1) Preparation of pseudo-boehmite PA4:

into a2 liter three-neck flask with stirring and reflux condenser, 1000 g of isopropyl alcohol-water azeotrope (water content 15 wt%) was added, 4.6mL of 85% concentrated phosphoric acid and 8 g of magnesium nitrate were added, the pH was adjusted to 5.1 by adding ammonia water, then heated to 60 ℃, 500 g of melted aluminum isopropoxide was slowly dropped into the flask through a separating funnel, reacted for 2 hours, then adjusted to 8.5 by adding ammonia water, after reflux reaction for 20 hours, dehydrated isopropyl alcohol was distilled off, aged for 6 hours at 80 ℃, aqueous isopropyl alcohol was distilled off while aging, and after aging, hydrated alumina was filtered, dried for 24 hours at 120 ℃ to obtain PA4. The composition of PA4, as calculated by XRD characterization, is listed in table 1, as characterized by XRD for PA4 having a pseudo-boehmite structure.

(2) 100 g of hydrated alumina PA4 and 30 g of Beta molecular sieve (product of medium petrochemical catalyst, kaolin Co., ltd., dry basis 80% by weight) calculated as alumina were weighed and mixed, and then carrier Z4 and catalyst C4 were prepared in the same manner as in example 1; the pore structure of the alumina obtained after firing PA4 at 600 ℃ for 3 hours was measured, and the results are shown in table 1, and the content of the metal oxide in C4 is shown in table 2.

Comparative example 3

The phosphorus-containing pseudo-boehmite is prepared according to the typical method in heavy oil hydrogenation catalyst carrier material research, and the concentration of 8.8mL of 85% concentrated phosphoric acid is 57 g.L ^-1 3000mL of aluminum sulfate solution with a concentration of 64 g.L ^-1 2500mL of sodium metaaluminate solution is subjected to precipitation reaction, the neutralization pH value is 8.0, the reaction time is 70min, then the aging is carried out, the aging temperature is 90 ℃, the aging pH value is 8.5, the filtering is carried out after the aging, the filter cake is pulped and washed by deionized water for 2 times, and the filter cake is dried at 120 ℃ for 24 hours to prepare the phosphorus-containing pseudo-boehmite CPA3. The composition of CPA3, as calculated by XRD characterization, is shown in Table 1, as characterized by XRD for CPA3 having a pseudo-boehmite structure.

The CPA3 was used to prepare carrier DZ3 and contrast DC3 as in example 1. The pore structure of the alumina obtained after CPA3 was calcined at 600 ℃ for 3 hours was measured, and the results are shown in table 1, and the content of the metal oxide in DC3 is shown in table 2.

Example 5

Pseudo-boehmite and alumina carrier were prepared as in example 1 except that 2 g of sodium acetate was further added to the aluminum sulfate solution to obtain PA5. The composition of PA5, as calculated by XRD characterization, is set forth in table 1, as characterized by XRD for PA5 having a pseudo-boehmite structure. PA5 was prepared as in example 1 as support Z5 and hydrogenation catalyst C5. The pore structure of the alumina obtained after firing PA5 at 600 ℃ for 3 hours was measured, and the results are shown in table 1, and the content of the metal oxide in C5 is shown in table 2.

Example 6

Pseudo-boehmite and alumina carrier were prepared as in example 1 except that 4g of ammonium fluoride was also added to the aluminum sulfate solution to give PA6.

The composition of PA6, as calculated by XRD characterization, is set forth in table 1, as characterized by XRD for PA6 having a pseudo-boehmite structure. PA6 was prepared as in example 1, support Z6 and catalyst C6; the pore structure of the alumina obtained after firing PA6 at 600 ℃ for 3 hours was measured, and the results are shown in table 1, and the content of the metal oxide in C6 is shown in table 2.

Comparative example 4

The procedure of example 1 was followed except that PA1 was calcined at 350 ℃ for 3 hours prior to the preparation of the support with the hydrogenation active metal, support DZ4 was prepared as in example 1 and the comparative catalyst was DC4, the catalyst metal component content being shown in table 2.

Example 7

Catalyst C7 was prepared using support Z1 of example 1 and in the same manner as in example 1, except that the hydrogenation-active metal component was introduced by kneading, specifically:

1000 g of PA1 and 500 g of Y molecular sieve (product of China petrochemical catalyst, namely, kaolin division company, the dry basis content is 83%), 195 g of molybdenum oxide and 46 g of nickel oxide are mixed uniformly, 1320 ml of aqueous solution containing 25g of nitric acid is added for mixing, then a butterfly wet strip with the outer diameter of 1.7mm is extruded on a plunger type strip extruder, the butterfly wet strip is dried for 4 hours at 130 ℃, and the temperature rising speed of 180 ℃/h is increased to 650 ℃ for roasting for 3 hours, so that the hydrogenation catalyst C7 is obtained. The metal oxide content of the hydrogenation catalyst is shown in table 2.

TABLE 1

Note that: v (V) _{Middle hole} Refers to the mesoporous pore volume with the pore distribution of 3-100nm, and the unit is mL/g; v (V) _{Macropores are formed} Refers to the macropore pore volume with the pore distribution of 100-5000nm, and the unit is mL/g; v (V) _{Total (S)} Refers to the total pore volume in mL/g.

As can be seen from the results of Table 1, the pseudo-boehmite containing phosphorus and magnesium prepared by the method of the present invention has a bimodal pore structure, which is measured by mercury intrusion, with a pore distribution of a mesopore volume V ranging from 3 to 100nm _{Middle hole} 0.9-1.4mL/g, a macropore pore volume V with a pore distribution of 100-5000nm _{Macropores are formed} 1.8-2.5mL/g, total pore volume V _{Total (S)} 2.7-3.9mL/g, and various pseudo-boehmite V prepared by the prior art method and the method in the comparative example _{Middle hole} Are all below 0.7, V _{Macropores are formed} Are all below 1, total pore volume V _{Total (S)} Are all below 2.

TABLE 2

Evaluation example

The following hydrodesulfurization test and hydrodenitrogenation test were performed on the hydrogenation catalysts prepared in the above 4mL examples 1 to 7 and comparative examples 1 to 4, respectively, using a WFSP3050 continuous high pressure reactor manufactured by Tianjin, inc. The catalyst was presulfided prior to testing. The pre-vulcanization conditions included: the vulcanized oil adopts cyclohexane containing 5w percent of carbon disulfide, and the liquid hourly space velocity of the vulcanized oil is 1.2h ^-1 The hydrogen partial pressure is 6MPa, the hydrogen oil volume ratio is 500, and the constant temperature is kept at 360 ℃ for 3 hours.

The hydrodesulfurization test method comprises the following steps: n-decane solution with the mass content of 1% of 4, 6-dimethyl dibenzothiophene (4, 6-DMDBT) is used as raw oil, then the reaction is carried out for 5 hours under the conditions of 6MPa,360 ℃ and hydrogen oil volume ratio of 300 and oil inlet flow of 8mL/h, sampling is carried out after the reaction is carried out for 6 hours, a sample is analyzed by an HS-500 type high-frequency infrared sulfur nitrogen analyzer, the activity is expressed by the desulfurization rate (average value of 10 samples) of the 4,6-DMDBT, and the result is shown in Table 3.

The hydrodenitrogenation test method comprises the following steps: taking an n-heptane solution with the mass content of quinoline (Q) of 1% as raw oil, then reacting for 3 hours under the conditions of 4.0MPa,350 ℃ and hydrogen oil volume ratio of 400 and oil inlet flow of 8mL/h, sampling after reacting for 4 hours, analyzing a sample by using an HS-500 type high-frequency infrared sulfur nitrogen analyzer, and expressing the activity by using the denitrification rate (average value of 10 samples) of the quinoline (Q), wherein the result is shown in Table 3.

The desulfurization (nitrogen) rate X of the reaction is calculated as follows:

the aromatic hydrogenation activity test method comprises the following steps: the catalytic performance of the hydrogenation catalysts prepared in example 1 and comparative example 3 was evaluated using tetrahydronaphthalene as a model compound. The specific method comprises the following steps: crushing the catalyst into particles with the diameter of 0.3-0.45 mm, loading 2mL of the catalyst into a fixed bed reactor, and vulcanizing the catalyst under the following conditions before oil filling: heating to 60 ℃ under the condition of hydrogen partial pressure of 4MPa, and then introducing CS ₂ N-hexane solution with 5 wt% content is heated to 310 deg.c and maintained for 4 hr to obtain vulcanized oil with liquid hourly space velocity of 1.2 hr ^-1 Hydrogen oil volume ratio 400. After the vulcanization is completed, the raw oil (i.e., the n-octane solution with tetrahydronaphthalene content of 5.61 wt%) is introduced to react under the following reaction conditions: the temperature is 390 ℃, the pressure is 4.0MPa, the hydrogen-oil volume ratio is 1000, and the liquid hourly space velocity is 2 hours ^-1 The results are shown in Table 3.

The catalytic activity of the catalyst was calculated using the following formula:

aromatic hydrocarbon hydroconversion activity = {1- [ (total amount of tetrahydronaphthalene in product + total amount of naphthalene in product)/total amount of tetrahydronaphthalene in feedstock ] } ×100%.

As can be seen from Table 3, the hydrogenation catalyst provided by the invention has better hydrodesulfurization, denitrification and aromatic hydrogenation activities under the same other conditions.

TABLE 3 Table 3

Examples numbering	Catalyst numbering	Denitrification rate/%	Desulfurization rate/%	Aromatic hydrogenation Activity/%
					1	C1	98.4	98.6	84.6
Comparative example 1	DC1	77.8	74.6	61.0
					Comparative example 2	DC2	77.5	76.9	61.2
2	C2	97.1	98.7	85.1
					3	C3	97.9	96.5	86.0
4	C4	98.2	96.5	85.1
					Comparative example 3	DC3	75.5	70.9	59.8
5	C5	96.2	99.5	85.1
					6	C6	97.2	96.5	84.3
Comparative example 4	DC4	78.5	70.9	61.2
					7	C7	98.4	97.5	86.4

The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the scope of the technical idea of the invention, a number of simple variants of the technical solution of the invention are possible, including combinations of the individual technical features in any other suitable way, which simple variants and combinations should likewise be regarded as being disclosed by the invention, all falling within the scope of protection of the invention.

Claims

1. A composite carrier comprising phosphorus and magnesium containing pseudo-boehmite and a solid acid, wherein the phosphorus and magnesium containing pseudo-boehmite has a bimodal pore structure as measured by mercury intrusion method, and the pore distribution is at a mesopore volume V of 3-100nm _{Middle hole} 0.7-1.7mL/g, a macropore pore volume V with a pore distribution of 100-5000nm _{Macropores are formed} 1.7-4.7mL/g, total pore volume V _{Total (S)} 2.4-6.4mL/g.

2. The composite carrier according to claim 1, wherein the solid acid is present in an amount of 1-99 parts by weight, preferably 5-80 parts by weight, based on the total amount of dry basis of the composite carrier; preferably, the solid acid is silica-alumina and/or a molecular sieve selected from at least one of faujasites, beta zeolites, omega zeolites, mordenite, ZSM-5 zeolites, ZSM-11 zeolites, ZSM-22 zeolites, ZSM-23 zeolites, ZSM-35 zeolites, ZSM-48 zeolites, ZSM-57 zeolites, erionite zeolites and ZSM-34 zeolites.

3. The composite carrier of claim 1, wherein the pseudo-boehmite containing phosphorus and magnesium is prepared byThe pore distribution of the alumina containing phosphorus and magnesium obtained after roasting at 600 ℃ for 3 hours is positioned at the mesoporous pore volume V of 3-100nm _{Middle hole} 0.9-1.5mL/g, a macropore pore volume V with a pore distribution of 100-5000nm _{Macropores are formed} 1.8-3.2mL/g, total pore volume V _{Total (S)} 2.7-4.7mL/g;

preferably, the pseudo-boehmite containing phosphorus and magnesium also contains auxiliary elements, and the auxiliary elements comprise metal auxiliary elements and/or non-metal auxiliary elements; the metal auxiliary element is at least one of lithium, sodium, potassium, rubidium, cesium, francium, beryllium, calcium, zirconium and titanium; the nonmetallic auxiliary agent element is at least one selected from boron element, fluorine element and silicon element;

preferably, al is based on the total amount of pseudo-boehmite dry basis containing phosphorus and magnesium ₂ O ₃ The content of (2) is 84 to 99.8 wt%, more preferably 84 to 99.7 wt%; p (P) ₂ O ₅ The content of (C) is 0.1-6 wt.%, the content of MgO is 0.1-5 wt.%, and the content of the auxiliary element is 0-5 wt.%, more preferably 0.1-5 wt.%.

4. A method for preparing a composite carrier, the method comprising the steps of:

5. The preparation method according to claim 4, wherein the precipitation reaction or the hydrolysis reaction of step (1) is performed at a pH of 4 to 6.5; the temperatures of the precipitation reaction and the hydrolysis reaction are each independently 30-90 ℃; the conditions of the precipitation reaction include: the reaction temperature is 40-90 ℃, preferably 45-80 ℃, and the reaction time is 10-60 minutes, preferably 10-30 minutes; the conditions of the hydrolysis reaction include: the reaction temperature is 40-90 ℃, preferably 45-80 ℃, and the reaction time is 2-30 hours, preferably 2-20 hours;

the inorganic aluminum-containing compound is aluminum salt and/or aluminate; the organic aluminum-containing compound is at least one of aluminum alkoxides which can generate hydrated aluminum oxide precipitation through hydrolysis reaction with water;

the phosphorus-containing compound is at least one selected from phosphoric acid, ammonium phosphate, ammonium hydrogen phosphate, diammonium hydrogen phosphate, sodium phosphate and potassium phosphate; the magnesium-containing compound is one or more selected from magnesium chloride, magnesium nitrate, magnesium sulfate and magnesium acetate;

the acid is at least one of sulfuric acid, hydrochloric acid, nitric acid, carbonic acid, phosphoric acid, formic acid, acetic acid, citric acid and oxalic acid; the alkali is at least one of sodium metaaluminate, potassium metaaluminate, sodium hydroxide, potassium hydroxide and ammonia water.

6. The process according to claim 4, wherein the aging in step (2) is performed at a pH of 8 to 10; the aging conditions include: the temperature is 50-95deg.C, preferably 55-90deg.C; the time is 0.5-8 hours, preferably 2-6 hours; the drying conditions in step (2) include: the temperature is 50-350deg.C, preferably 80-250deg.C, and the drying time is 1-12 hr, preferably 2-8 hr.

7. The production method according to claim 4, wherein the precipitation reaction or the hydrolysis reaction in step (1) further comprises adding an optional auxiliary element-containing compound, the auxiliary elements comprising a metal auxiliary element and/or a non-metal auxiliary element;

the metal auxiliary element is at least one of lithium, sodium, potassium, rubidium, cesium, francium, beryllium, calcium, zirconium and titanium, more preferably at least one of lithium, sodium, potassium, beryllium, calcium, zirconium and titanium; the nonmetallic auxiliary agent element is at least one selected from boron element, fluorine element and silicon element;

the content of each component is such that Al is based on the total amount of the alumina containing phosphorus and magnesium in the obtained alumina containing phosphorus and magnesium ₂ O ₃ The content of P is 85-99.8 wt%, more preferably 85-99.7 wt% ₂ O ₅ The content of (2) is 0.1-5 wt.%, the content of MgO is 0.1-5 wt.%, the content of auxiliary elements is 0-5 wt.%, more preferably 0.1-5 wt.%.

8. The method according to claim 4, wherein the composite carrier is prepared without calcination.

9. A hydrogenation catalyst, comprising a carrier and a hydrogenation active metal component supported on the carrier, wherein the hydrogenation active metal component contains at least one VIB group metal component and at least one VIII group metal component, the content of the carrier is 30-99 wt%, the content of the VIB group metal component is 0.5-50 wt% and the content of the VIII group metal component is 0.5-20 wt% based on the total amount of the catalyst; the carrier is a composite carrier according to any one of claims 1-3 or a composite carrier prepared by a method according to any one of claims 4-8.

10. The catalyst according to claim 9, wherein the group VIB metal component is Mo and/or W and the group VIII metal component is Co and/or Ni; based on the total catalyst, the catalyst comprises 40-94 wt% of a carrier, 5-45 wt% of a group VIB metal component and 1-15 wt% of a group VIII metal component, calculated as oxides;

the catalyst is subjected to hydrogen temperature programmed reduction method (H ₂ -TPR) peak height P of the low temperature reduction peak at 300-500 DEG C _{Low temperature peak} Peak height P with high temperature reduction peak at 650-850 deg.c _{High temperature peak} Ratio s=p of (2) _{Low temperature peak} /P _{High temperature peak} 0.5-2.0; preferably, the peak height P of the low temperature reduction peak _{Low temperature peak} With high temperature reductionPeak height P of peak _{High temperature peak} Ratio s=p of (2) _{Low temperature peak} /P _{High temperature peak} From 0.7 to 1.9, preferably from 0.8 to 1.8.

11. A method of preparing a hydrogenation catalyst, the method comprising: loading hydrogenation active metal components on the composite carrier according to any one of claims 1-3 or the composite carrier prepared by the method according to any one of claims 4-8, and drying and roasting to obtain the hydrogenation catalyst;

the hydrogenation active metal component comprises at least one VIB metal component and at least one VIII metal component; the components are used in amounts such that the final catalyst has a content of 30 to 99 wt.%, calculated as oxides, of the carrier and a content of 0.5 to 50 wt.%, calculated as oxides, of the group VIB metal component and a content of 0.5 to 20 wt.%.

12. The production method according to claim 11, wherein the drying condition is: the temperature is 50-350 ℃, and the drying time is 1-12 hours; the roasting conditions are as follows: the temperature is 400-1000deg.C, preferably 410-880 deg.C, more preferably 430-850 deg.C, for 1-10 hr, and the heating rate is 50-600deg.C/hr, preferably 100-550deg.C/hr.

13. The process according to claim 11, wherein the method of loading the hydrogenation-active metal component onto the composite carrier is an impregnation method comprising impregnating the composite carrier with an impregnation solution comprising at least one group VIB metal compound and at least one group VIII metal compound;

the VIB metal component is Mo and/or W, and the VIII metal component is Co and/or Ni; the components are used in such amounts that the content of the carrier is 40-94 wt.%, calculated as oxides, of the group VIB metal component and the group VIII metal component is 1-15 wt.%, based on the total amount of the catalyst, in the final catalyst.

14. Use of a hydrogenation catalyst according to claim 9 or 10 or a hydrogenation catalyst prepared by a process according to any one of claims 11 to 13 in the hydrogenation of hydrocarbon oils.