Hydrofining catalyst as well as preparation method and application thereof

Abstract

The invention relates to the technical field of hydrofining, and discloses a hydrofining catalyst as well as a preparation method and application thereof. The method comprises the following steps: (1) sequentially carrying out mixing and kneading, extrusion molding, first drying and roasting on aluminum oxide and an adhesive to obtain a catalyst carrier; and (2) impregnating the catalyst carrier in an impregnation liquid containing an active metal salt and a complexing agent, then separating out a solid phase, and carrying out secondary drying to obtain the hydrofining catalyst, (3) activating the hydrofining catalyst in a hydrogen atmosphere; wherein the complexing agent is selected from at least one of ethylenediaminetetraacetic acid, amine trimethylene phosphate, tartaric acid, thioglycollic acid, citric acid, malic acid, glycolic acid, glycine and glycollic acid. The hydrofining catalyst provided by the invention has the advantages of small metal loading amount and good metal dispersibility, can effectively reduce the contents of unsaturated olefin, oxygen-containing compounds and the like in raw materials, and obviously improves the product quality.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of hydrofining technology, in particular to a hydrofining catalyst and a preparation method and application thereof. BACKGROUND

[0002] Fischer-Tropsch synthesis is a process for synthesizing liquid fuels and chemicals mainly composed of long-chain alkanes from hydrogen and carbon monoxide as raw materials under the catalysis of a catalyst and appropriate reaction conditions. The main component is long-chain alkanes, and almost no sulfur, nitrogen, and aromatic hydrocarbons are contained. The stable heavy oil of Fischer-Tropsch synthesis contains about 60% of alpha-olefins, which is a high-quality raw material for producing high-grade base lubricating oil. Poly-alpha-olefins (PAO) as a fully synthetic lubricating oil base oil have better viscosity-temperature performance and low-temperature flowability than mineral lubricating oil base oil. About 80% of low-viscosity PAO is used as car internal combustion engine oil, gear oil, hydraulic oil, etc.

[0003] The traditional petroleum-based poly-alpha-olefins contain unsaturated olefins, trace amounts of sulfur and nitrogen, and aromatic hydrocarbons, which can seriously affect the color, stability, and performance of the product. In view of this situation, the method of hydrofining is usually used in industry to improve the stability of the quality of PAO products. Since the poly-alpha-olefins obtained by oligomerization are mainly macromolecules, the steric hindrance is large, which leads to the relative difficulty of hydrogenation saturation of unsaturated hydrocarbons; in addition, too high catalyst activity can lead to hydrogenolysis and isomerization of poly-alpha-olefins. In order to solve these problems, the catalyst for hydrofining treatment of PAO crude products is usually synthesized by using noble metals, high-content non-noble metal catalysts, and complex co-precipitation method, however, such catalysts not only contain a small amount of noble metals and high-content non-noble metals, but also have a complex synthesis process, which increases the production cost.

[0004] At present, the catalysts for poly-alpha-olefin hydrogenation mainly include Raney nickel and impregnation method supported catalysts. Although Raney nickel can achieve a certain hydrogenation effect, Raney nickel is unstable in air and can easily burn in the presence of oxygen, which brings great inconvenience to storage and use. Although the impregnation method is simple in process and can save metal, the activity of the metal component is poor, and the service life of the catalyst is short and easy to deactivate, and the cost increases after adding noble metals, which is not suitable for current industrialization. SUMMARY

[0005] The present application aims to overcome the problems of complex catalyst production process, high production cost, low hydrogenation activity, poor metal dispersion, poor adaptability and high safety risk in the prior art, and provides a hydrofining catalyst, a preparation method and application thereof. The hydrofining catalyst selects a material with large pore volume and pore size as a catalyst carrier, loads a single metal element, uses an organic complexing agent to improve metal dispersion and control metal grain size. The catalyst has large pore volume and pore size and high hydrogen capacity, increases the hydrogenation / dehydrogenation probability of the reaction medium at the catalytically active center, and the large pore size can improve the adsorption / diffusion rate of the reaction medium in the catalyst pores to inhibit the probability of occurrence of side reactions such as carbon chain isomerization and hydrogenolysis. By controlling the morphology of the metal active phase, the effective activity of the metal is improved, and the probability of hydrogenolysis of the reaction medium is reduced, thereby ensuring the liquid yield, viscosity index and other indicators of the hydrogenation product. Moreover, the catalyst does not need to be calcined during preparation and does not need a sulfidation process during activation, which has very important economic and environmental benefits in reducing catalyst manufacturing cost, production cost and production safety risk.

[0006] To achieve the above-mentioned object, the first aspect of the present application provides a preparation method of a hydrofining catalyst, the method comprising the following steps:

[0007] (1) kneading, extruding, first drying and calcining alumina and a binder in sequence to obtain a catalyst carrier;

[0008] (2) impregnating the catalyst carrier in an impregnation solution containing an active metal salt and a complexing agent, then separating the solid phase and performing second drying to obtain a hydrofining catalyst;

[0009] The complexing agent is at least one selected from ethylenediaminetetraacetic acid, amine trimethylphosphonate, tartaric acid, thio glycolic acid, citric acid, malic acid, glycolic acid, amino acetic acid and glycolic acid.

[0010] Preferably, in step (1), the alumina is at least one selected from γ-Al2O3, δ-Al2O3, η-Al2O3 and α-Al2O3.

[0011] Preferably, in step (1), the binder is at least one selected from pseudoboehmite, silica sol, aluminum sol and water glass.

[0012] Preferably, in step (1), the content of the alumina in the catalyst carrier is 60-90wt%, and the content of the binder is 5-40wt%.

[0013] Preferably, in step (1), the first drying conditions include a temperature of 100-300℃ and a time of 0.5-24h.

[0014] Preferably, in step (1), the conditions of the calcination include: temperature of 300-600℃, time of 0.5-24h.

[0015] Preferably, in step (2), the active metal salt is at least one of the salts containing metals of Group VIII and Group VIB.

[0016] Preferably, the active metal salt is a cobalt salt and / or a nickel salt.

[0017] Preferably, the active metal salt is nickel nitrate.

[0018] Preferably, the mass ratio of the catalyst carrier and the amount of the active metal salt is 1:(0.1-0.4).

[0019] Preferably, in step (2), the molar ratio of the complexing agent and the amount of the active metal salt is (0.2-1):1.

[0020] Preferably, in step (2), the conditions of the second drying include: temperature of 40-200℃, time of 0.5-12h.

[0021] The second aspect of the present application provides a hydrofining catalyst prepared by the above method.

[0022] The third aspect of the present application provides the use of the above hydrofining catalyst in the hydrogenation of poly-α-olefin oil.

[0023] Compared with the prior art, the present application has the following technical effects:

[0024] (1) For the feedstock oil of Fischer-Tropsch synthesis oil-based PAO, a porous material with large pore volume and large pore size is used as the carrier to improve the mass transfer rate of the reaction medium, and the hydrogenation capacity of the hydrofining catalyst is improved, thereby reducing the possibility of isomerization and hydrogenolysis of the reactants;

[0025] (2) By selecting a specific complexing agent to control the number of metal active sites and the size of metal grains, the metal can be better dispersed on the catalyst, the effective metal content can be increased, the size of the metal grains can be controlled, and hydrogenolysis caused by excessive metal activity can be prevented.

[0026] (3) The hydrofining catalyst described in the present application has less metal loading, good metal dispersity, does not need to be calcined, has low manufacturing cost, and can be activated in a non-sulfurized manner, thereby having low operating cost.

[0027] The use of the catalyst of the present application for the hydrofining of poly-α-olefin can effectively reduce the content of unsaturated olefins, oxygen-containing compounds, etc. in the raw material, and significantly improve the product quality. DETAILED DESCRIPTION

[0028] The specific embodiments of the present application are described in detail below. It should be understood that the detailed description and specific examples described herein are intended for purposes of illustration only and are not intended to limit the present application.

[0029] The endpoints of the ranges and any values disclosed herein are not limited to the precise values recited as exactly that endpoint. Any values that fall within the range of values are included in the range unless the context clearly indicates otherwise. Thus, for example, if the range is 1 to 5, then values of 2, 2.33, 2.67, 3, 3.33, 3.67, 4, and 5 are included in the range as proprietary endpoints.

[0030] The method for preparing the hydrofining catalyst according to the present application comprises the following steps:

[0031] (1) kneading, extruding, first drying and calcining the alumina and the binder in sequence to obtain a catalyst carrier;

[0032] (2) impregnating the catalyst carrier in an impregnation solution containing an active metal salt and a complexing agent, then separating the solid phase and performing second drying to obtain a hydrofining catalyst;

[0033] The complexing agent is at least one selected from ethylenediaminetetraacetic acid, amine trimethylphosphonate, tartaric acid, thioglycolic acid, citric acid, malic acid, glycolic acid, aminoacetic acid and glycolic acid.

[0034] According to the method of the present application, the porous material with large pore volume and large pore size is used as the carrier to improve the mass transfer rate of the reaction medium, and the hydrogenation capacity of the hydrofining catalyst is improved, thereby reducing the possibility of isomerization and hydrogenolysis of the reactants. In addition, by selecting a specific complexing agent to control the number of metal active sites and the size of metal grains, the metal can be better dispersed on the catalyst, the effective metal content can be increased, the size of the metal grains can be controlled, and hydrogenolysis caused by excessively high metal activity can be prevented. The prepared hydrofining catalyst has the advantages of low metal loading, good metal dispersion, no need for calcination for loading, low manufacturing cost, and the ability to be activated in a non-sulfurized manner, thereby reducing the operating cost.

[0035] In the method of the present application, in step (1), the alumina can be at least one selected from the group consisting of γ-Al2O3, δ-Al2O3, η-Al2O3 and α-Al2O3, preferably δ-Al2O3 and γ-Al2O3. In a preferred embodiment, the alumina is δ-Al2O3 and γ-Al2O3, and the mass ratio of the amount of δ-Al2O3 to the amount of γ-Al2O3 is 3:(7-18). The purity of the alumina is greater than 98%. The pore volume (BET) of the alumina can be 0.8-1.2 mL / g. The pore volume (mercury porosimetry) of the alumina can be 0.9-1.5 mL / g. The specific surface area of the alumina can be 200-600 m 2 / g.

[0036] In the method of the present application, in step (1), in order to improve the mass transfer efficiency, the binder is preferably at least one selected from the group consisting of pseudoboehmite, silica sol, alumina sol and water glass, more preferably pseudoboehmite. The peptization index of the pseudoboehmite can be 95 wt% or more, preferably 98 wt% or more.

[0037] In the method of the present application, in step (1), in the catalyst carrier, the content of the alumina can be 60-90 wt%, preferably 70-80 wt%; the content of the binder can be 5-40 wt%, preferably 20-30 wt%.

[0038] In the method of the present application, in step (1), the specific step of kneading the alumina and the binder can include: mixing the alumina and the binder, and then adding nitric acid under stirring to knead. The stirring conditions include: the stirring rate can be 20-60 rpm, preferably 30-40 rpm; the temperature can be 10-40℃, preferably 15-30℃; the time can be 0.2-1 h, preferably 0.4-0.7 h. The concentration of the nitric acid can be 0.03 wt%-0.1 wt%, preferably 0.04 wt%-0.06 wt%. The mass ratio of the total mass of the alumina and the binder to the mass of the nitric acid can be 1:(0.9-1.2), preferably 1:(0.9-1).

[0039] In a preferred embodiment, the alumina is δ-Al2O3 and γ-Al2O3, and the mass ratio of the amount of δ-Al2O3 to the amount of γ-Al2O3 is 3:(7-18), and the binder is pseudoboehmite.

[0040] In the method of the present application, in step (1), the first drying conditions include: the temperature can be 100-300℃, preferably 150-200℃; the time can be 0.5-24 h, preferably 2-6 h.

[0041] In the method of the present application, in step (1), the calcination conditions include: the temperature can be 300-600°C, preferably 400-600°C; the time can be 0.5-24h, preferably 2-6h.

[0042] In the method of the present application, in step (2), the active metal salt can be at least one of the salts containing metals of Group VIII and Group VIB, preferably cobalt salt and / or nickel salt, more preferably nickel nitrate. The cobalt salt can be at least one of cobalt nitrate, cobalt carbonate and cobalt acetate, preferably cobalt nitrate. The nickel salt can be at least one of nickel nitrate, nickel carbonate and nickel acetate, preferably nickel nitrate. In the hydrofining catalyst, the content of active metal oxide can be 3-10wt%.

[0043] In the method of the present application, in order to improve the dispersion of the metal, in step (2), the mole ratio of the amount of the complexing agent to the amount of the active metal salt is preferably (0.2-1) : 1, more preferably (0.3-0.8) : 1. The complexing agent can be at least one selected from ethylenediaminetetraacetic acid, amine trimethylphosphonate, tartaric acid, thioglycolic acid, citric acid, malic acid, glycolic acid, aminoacetic acid and glycolic acid, preferably glycolic acid. The solvent of the impregnation solution can be water.

[0044] In the preferred embodiment, in the impregnation solution, the complexing agent is glycolic acid, the active metal salt is nickel nitrate, and the mole ratio of the amount of glycolic acid to the amount of nickel nitrate is (0.2-1) : 1. The mass ratio of the amount of the catalyst carrier to the amount of the active metal salt can be 1 : (0.1-0.4), preferably 1 : (0.16-0.3).

[0045] In the method of the present application, the method further comprises preparing the impregnation solution by mixing the active metal salt, the complexing agent and water at 10-40°C for 0.3-1h.

[0046] In the method of the present application, in step (2), the impregnation conditions include: the temperature can be 10-40°C, preferably 15-30°C; the time can be 0.2-1h, preferably 0.3-0.6h.

[0047] In the method of the present application, in step (2), the second drying conditions include: the temperature can be 40-200°C, preferably 100-150°C; the time can be 0.5-12h, preferably 1-4h.

[0048] In the method of the present application, the method further comprises activating the hydrofining catalyst under a hydrogen atmosphere. The conditions for activating under a hydrogen atmosphere include that the hydrogen partial pressure can be 0-5 MPa, preferably 2-4 MPa; the temperature can be 100-500°C, preferably 100-300°C; and the time can be 1-48 h, preferably 2-12 h. The hydrogen partial pressure is the gauge pressure.

[0049] In some embodiments, the method for preparing the hydrofining catalyst of the present application comprises the following steps:

[0050] (1) mixing alumina and a binder, adding nitric acid with a concentration of 0.03wt%-0.1wt% at 10-40°C under stirring at a stirring rate of 20-60 rpm, and then kneading for 0.2-1 h, followed by extruding into a strip, and then first drying at 100-300°C for 0.5-24 h, and then calcining at 300-600°C for 0.5-24 h to obtain a catalyst carrier, wherein the content of the alumina is 60-90wt%, the content of the binder is 5-40wt%, and the mass ratio of the total mass of the alumina and the binder to the mass of the nitric acid is 1:(0.9-1.2);

[0051] (2) mixing an active metal salt, a complexing agent, and water at 10-40°C for 0.3-1 h to obtain an impregnation solution, impregnating the catalyst carrier in the impregnation solution at 10-40°C for 0.2-1 h, then separating the solid phase and second drying at 40-200°C for 0.5-12 h to obtain a hydrofining catalyst;

[0052] wherein the complexing agent is at least one selected from ethylenediaminetetraacetic acid, amine trimethylphosphonate, tartaric acid, thioglycolic acid, citric acid, malic acid, glycolic acid, aminoacetic acid, and glycolic acid; the alumina is at least one selected from γ-Al2O3, δ-Al2O3, η-Al2O3, and α-Al2O3; the binder is at least one selected from pseudoboehmite, silica sol, aluminum sol, and water glass; the active metal salt can be at least one of a salt containing metals of Group VIII and Group VIB; the molar ratio of the amount of the complexing agent to the amount of the active metal salt is (0.2-1):1; and the mass ratio of the amount of the catalyst carrier to the amount of the active metal salt is 1:(0.1-0.4).

[0053] In other embodiments, the method for preparing the hydrofining catalyst of the present application comprises the following steps:

[0054] (1) mixing δ-Al2O3, γ-Al2O3 and pseudoboehmite, adding nitric acid with a concentration of 0.03wt%-0.1wt% at a stirring speed of 30-40rpm, and kneading at 15-30℃ for 0.4-0.7h, then extruding into strips, and then first drying at 100-300℃ for 0.5-24h, and then calcining at 300-600℃ for 0.5-24h to obtain a catalyst carrier, wherein the total content of δ-Al2O3 and γ-Al2O3 is 60-90wt%, the content of pseudoboehmite is 5-40wt%, the mass ratio of the total mass of δ-Al2O3, γ-Al2O3 and pseudoboehmite to the mass of the nitric acid is 1:(0.9-1.2), and the mass ratio of the amount of δ-Al2O3 to the amount of γ-Al2O3 is 3:(7-18);

[0055] (2) mixing nickel nitrate, glycolic acid and water at 10-40℃ for 0.3-1h to obtain an impregnation solution, impregnating the catalyst carrier in the impregnation solution at 15-30℃ for 0.3-0.6h, then separating the solid phase and second drying at 40-200℃ for 0.5-12h to obtain a hydrofining catalyst;

[0056] wherein the molar ratio of the amount of glycolic acid to the amount of nickel nitrate is (0.2-1):1, and the mass ratio of the amount of the catalyst carrier to the amount of nickel nitrate is 1:(0.1-0.4).

[0057] The second aspect of the present application provides a hydrofining catalyst prepared by the above method. The hydrofining catalyst according to the present application has a low metal loading, a good metal dispersion, does not need to be calcined, has a low manufacturing cost, and can be activated in a non-sulfurized manner. The hydrofining catalyst according to the present application has a high hydrogen capacity, increases the hydrogenation / dehydrogenation probability of the reaction medium at the catalytically active center, a large pore size improves the adsorption / diffusion rate of the reaction medium in the pores of the catalyst, thereby reducing the probability of the occurrence of side reactions such as carbon chain isomerization and hydrogenolysis, and by controlling the morphology of the metal active phase, the effective activity of the metal is improved while the probability of hydrogenolysis of the reaction medium is reduced, thereby ensuring the liquid yield, viscosity index and other indicators of the hydrogenation product.

[0058] In the hydrofining catalyst described in the present application, the hydrofining catalyst can contain alumina, a binder and active metal oxide. The alumina can be selected from at least one of γ-Al2O3, δ-Al2O3, η-Al2O3 and α-Al2O3, preferably δ-Al2O3 and γ-Al2O3. The binder can be selected from at least one of pseudoboehmite, silica sol, alumina sol and water glass, preferably pseudoboehmite. The active metal oxide can be selected from at least one of oxides of metals of Group VIII and Group VIB, preferably nickel oxide and / or cobalt oxide, more preferably nickel oxide.

[0059] In the hydrofining catalyst described in the present application, the content of the alumina can be 60-90 wt%, preferably 70-80 wt%, based on the total weight of the hydrofining catalyst; the content of the binder can be 5-40 wt%, preferably 15-30 wt%; and the content of the active metal oxide can be 3-10 wt%, preferably 5-8 wt%.

[0060] In a preferred embodiment, the hydrofining catalyst contains δ-Al2O3, γ-Al2O3, pseudoboehmite and nickel; the content of δ-Al2O3 is 5-27 wt%, the content of γ-Al2O3 is 42-80 wt%, the content of pseudoboehmite is 5-40 wt%, and the content of nickel oxide is 3-10 wt%, based on the total weight of the hydrofining catalyst.

[0061] In the hydrofining catalyst described in the present application, the specific surface area of the hydrofining catalyst can be 210-221 m 2 / g, preferably 215-220 m 2 / g. The pore volume (BET) of the hydrofining catalyst can be 0.0.6-0.8 mL / g, preferably 0.65-0.75 mL / g. The pore volume (pressure pump method) of the hydrofining catalyst can be 0.6-0.8 mL / g, preferably 0.65-0.75 mL / g. The average pore diameter of the hydrofining catalyst can be 13-14 nm, preferably 13.5-14 nm. In the hydrofining catalyst, the pore size distribution (according to dV / dlogD) is as follows: the pore volume ratio of pores with a pore diameter of 5-10 nm can be 18-20%, and the pore volume ratio of pores with a pore diameter greater than 10 nm can be 80-82%.

[0062] The third aspect of the present application provides the use of the above-mentioned hydrofining catalyst in the hydrogenation of poly-α-olefin oil. According to the use described in the present application, the hydrofining catalyst is used for the hydrofining of poly-α-olefin, which can effectively reduce the content of unsaturated olefins, oxygen-containing compounds and the like in the raw material, and significantly improve the product quality.

[0063] The hydrofining catalyst, the preparation method and the application thereof according to the present application are further illustrated by the following examples. The examples are implemented on the premise of the technical solutions of the present application, and detailed implementation modes and specific operation processes are given, but the protection scope of the present application is not limited to the following examples.

[0064] The experimental methods in the following examples are all conventional methods in the art unless otherwise specified. The experimental materials used in the following examples are all commercially available unless otherwise specified. The glycolic acid is purchased from Aladdin Reagent (Shanghai) Co., Ltd., and is of analytical purity; the citric acid is purchased from Weifang Yingxuan Industry Co., Ltd.

[0065] Example 1

[0066] (1) 24.52 g of δ-Al2O3 (pore volume (BET) 0.9 mL / g, pore volume (mercury porosimetry) 1.1 mL / g, specific surface area 340 m 2 / g), 147.14 g of γ-Al2O3 (pore volume (BET) 1.0 mL / g, pore volume (mercury porosimetry) 1.2 mL / g, specific surface area 350 m 2 / g) and 28.34 g of pseudoboehmite were mixed, and 190 g of nitric acid with a concentration of 0.04 wt% was added under stirring, and then kneaded at a stirring rate of 30 rpm at 20 °C for 0.7 h, followed by extrusion molding, and then dried at 150 °C for 2 h, and then calcined at 500 °C for 2 h to obtain a catalyst carrier (in the catalyst carrier, the content of δ-Al2O3 was 12.26 wt%, the content of γ-Al2O3 was 73.57 wt%, and the content of the pseudoboehmite was 14.17 wt%);

[0067] (2) 17.20 g of nickel nitrate hexahydrate, 0.90 g of glycolic acid and 100 mL of water were mixed at 15 °C for 0.5 h to obtain an impregnation solution (the molar ratio of the amount of use of glycolic acid to nickel nitrate hexahydrate was 0.2:1), and 100 g of the catalyst carrier was impregnated in the impregnation solution at 20 °C for 0.6 h, and then the solid phase was separated by filtration and dried at 150 °C for 2 h to obtain a hydrofining catalyst S1.

[0068] (3) The hydrofining catalyst was activated at 300 °C for 6 h under a hydrogen atmosphere with a hydrogen partial pressure of 3 MPa to obtain a hydrogen-activated catalyst S1.

[0069] Example 2

[0070] (1) 24.52 g of δ-Al2O3 (pore volume (BET) 0.9 mL / g, pore volume (mercury porosimetry) 1.1 mL / g, specific surface area 340 m 2 / g), 147.14g γ-Al2O3 (pore volume (BET) is 1.0mL / g, pore volume (mercury porosimetry) is 1.2mL / g, specific surface area is 350m² / g). 2 28.34 g of boehmite and 190 g of 0.04 wt% nitric acid were mixed and kneaded at 25 °C for 0.5 h with stirring at 30 rpm. The mixture was then extruded into strips, dried at 150 °C for 2 h, and calcined at 500 °C for 2 h to obtain a catalyst support (in the catalyst support, the content of δ-Al2O3 is 12.26 wt%, the content of γ-Al2O3 is 73.57 wt%, and the content of boehmite is 14.17 wt%).

[0071] (2) 24.42g of nickel nitrate hexahydrate, 3.83g of ethylene glycol and 100mL of water were mixed at 15°C for 0.7h to obtain an impregnation solution (the molar ratio of ethylene glycol and nickel nitrate was 0.6:1). 100g of the catalyst support was impregnated in the impregnation solution at 20°C for 0.6h. The solid phase was then separated by filtration and dried at 150°C for 2h to obtain the hydrorefining catalyst S2.

[0072] (3) The hydrogenation refining catalyst was activated at 300°C for 6 hours in a hydrogen atmosphere with a hydrogen partial pressure of 3 MPa to obtain hydrogenation activated catalyst S2.

[0073] Example 3

[0074] (1) 24.52g of δ-Al2O3 (pore volume (BET) is 0.9mL / g, pore volume (mercury porosimetry) is 1.1mL / g, specific surface area is 340m²) 2 / g), 147.14g γ-Al2O3 (pore volume (BET) is 1.0mL / g, pore volume (mercury porosimetry) is 1.2mL / g, specific surface area is 350m² / g). 2 28.34 g of boehmite and 190 g of 0.04 wt% nitric acid were mixed and kneaded at 25 °C for 0.4 h with stirring at 30 rpm. The mixture was then extruded into strips, dried at 150 °C for 2 h, and calcined at 500 °C for 2 h to obtain a catalyst support (in the catalyst support, the content of δ-Al2O3 is 12.26 wt%, the content of γ-Al2O3 is 73.57 wt%, and the content of boehmite is 14.17 wt%).

[0075] (2) 24.42 g of nickel nitrate hexahydrate, 6.39 g of glycolic acid, and 100 mL of water were mixed at 25°C for 0.5 h to obtain an impregnation solution (molar ratio of the amounts of use of glycolic acid and nickel nitrate: 1 : 1), 100 g of the catalyst support was impregnated in the impregnation solution at 25°C for 0.5 h, then the solid phase was separated by filtration and dried at 150°C for 2 h to obtain a hydrofining catalyst S3.

[0076] (3) The hydrofining catalyst was activated under a hydrogen atmosphere at a hydrogen partial pressure of 3 MPa at 300°C for 6 h to obtain a hydrogen-activated catalyst S3.

[0077] Example 4

[0078] (1) 24.52 g of δ-Al203(having a pore volume (BET) of 0.9 mL / g, a pore volume (mercury porosimetry) of 1.1 mL / g, and a specific surface area of 340 m 2 / g), 147.14 g of γ-Al203(having a pore volume (BET) of 1.0 mL / g, a pore volume (mercury porosimetry) of 1.2 mL / g, and a specific surface area of 350 m 2 / g), and 28.34 g of pseudoboehmite were mixed, 190 g of nitric acid having a concentration of 0.04% by weight was further added with stirring, kneading was performed at a stirring rate of 30 rpm at 25°C for 0.5 h, then extrusion molding was performed, followed by drying at 150°C for 2 h and calcination at 500°C for 2 h to obtain a catalyst support (in the catalyst support, the content of δ-Al203was 12.26% by weight, the content of γ-Al203was 73.57% by weight, and the content of the pseudoboehmite was 14.17% by weight);

[0079] (2) 24.42 g of nickel nitrate hexahydrate, 6.39 g of glycolic acid, and 100 mL of water were mixed at 25°C for 0.5 h to obtain an impregnation solution (molar ratio of the amounts of use of glycolic acid and nickel nitrate: 1 : 1), 100 g of the catalyst support was impregnated in the impregnation solution at 25°C for 0.5 h, then the solid phase was separated by filtration and dried at 150°C for 2 h to obtain a hydrofining catalyst S3.

[0080] (3) The hydrofining catalyst was activated under a hydrogen atmosphere at a hydrogen partial pressure of 3 MPa at 300°C for 6 h to obtain a hydrogen-activated catalyst S3.

[0081] Example 5

[0082] (1) 24.52 g of δ-Al203(having a pore volume (BET) of 0.9 mL / g, a pore volume (mercury porosimetry) of 1.1 mL / g, and a specific surface area of 340 m 2 / g), 126g γ-Al2O3 (pore volume (BET) is 1.0mL / g, pore volume (mercury porosimetry) is 1.2mL / g, specific surface area is 350m² / g). 2 The catalyst support is obtained by mixing 20g of silica sol with δ-Al2O3 (27wt%) and γ-Al2O3 (63wt%), and kneading at 30℃ for 0.6h with stirring at 30rpm. The mixture is then extruded into strips, dried at 100℃ for 24h, and calcined at 300℃ for 24h.

[0083] (2) Mix 16.10g of cobalt nitrate hexahydrate, 3.24g of ethylenediaminetetraacetic acid and 100mL of water at 30℃ for 0.5h to obtain an impregnation solution (the molar ratio of ethylenediaminetetraacetic acid and cobalt nitrate is 0.2:1). Impregnate 100g of the catalyst support in the impregnation solution at 30℃ for 0.5h. Then separate the solid phase by filtration and dry it at 40℃ for 12h to obtain the hydrorefining catalyst S5.

[0084] (3) The hydrogenation refining catalyst was activated at 100°C for 48 h in a hydrogen atmosphere with a hydrogen partial pressure of 0 MPa to obtain hydrogenation activated catalyst S5.

[0085] Example 6

[0086] (1) 20g of δ-Al2O3 (pore volume (BET) is 0.9mL / g, pore volume (mercury porosimetry) is 1.1mL / g, specific surface area is 340m²) 2 / g), 100g γ-Al2O3 (pore volume (BET) is 1.0mL / g, pore volume (mercury porosimetry) is 1.2mL / g, specific surface area is 350m² 2 The mixture of 80g of aluminum sol and 190g of 0.04wt% nitric acid was added under stirring and kneaded at 10℃ for 1h at a stirring rate of 20rpm. The mixture was then extruded into strips, dried at 300℃ for 0.5h, and calcined at 600℃ for 0.5h to obtain a catalyst support (in the catalyst support, the content of δ-Al2O3 is 10wt%, the content of γ-Al2O3 is 50wt%, and the content of aluminum sol is 40wt%).

[0087] (2) 12.53 g of nickel nitrate hexahydrate, 12.89 g of amine tris-methylidene phosphate and 100 mL of water were mixed at 10°C for 1 h to obtain an impregnation solution (molar ratio of the amounts of use of amine tris-methylidene phosphate and nickel nitrate was 1 : 1), 100 g of the catalyst support was impregnated in the impregnation solution at 10°C for 1 h, then the solid phase was separated by filtration and dried at 200°C for 0.5 h to obtain a hydrofmishing catalyst S6.

[0088] (3) The hydrofmishing catalyst was activated under a hydrogen atmosphere at a hydrogen partial pressure of 5 MPa at 500°C for 1 h to obtain a hydrogenation-activated catalyst S6.

[0089] Example 7

[0090] (1) 24.52 g of δ-Al203(having a pore volume (BET) of 0.9 mL / g, a pore volume (mercury porosimetry) of 1.1 mL / g and a specific surface area of 340 m 2 / g), 147.14 g of γ-Al203(having a pore volume (BET) of 1.0 mL / g, a pore volume (mercury porosimetry) of 1.2 mL / g and a specific surface area of 350 m 2 / g) and 28.34 g of water glass were mixed, 190 g of nitric acid having a concentration of 0.04 wt% was further added with stirring, kneading was performed at 40°C at a stirring rate of 60 rpm for 0.2 h, then extrusion molding was performed, followed by drying at 150°C for 2 h and calcination at 500°C for 2 h to obtain a catalyst support (in the catalyst support, the content of δ-Al203was 12.26 wt%, the content of γ-Al203was 73.57 wt% and the content of the water glass was 14.17 wt%);

[0091] (2) 41.67 g of nickel nitrate hexahydrate, 4.30 g of tartaric acid and 100 mL of water were mixed at 40°C for 0.3 h to obtain an impregnation solution (molar ratio of the amounts of use of tartaric acid and nickel nitrate was 0.2 : 1), 100 g of the catalyst support was impregnated in the impregnation solution at 40°C for 0.2 h, then the solid phase was separated by filtration and dried at 150°C for 2 h to obtain a hydrofmishing catalyst S7.

[0092] (3) The hydrofmishing catalyst was activated under a hydrogen atmosphere at a hydrogen partial pressure of 3 MPa at 300°C for 6 h to obtain a hydrogenation-activated catalyst S7.

[0093] Example 8

[0094] Prepared in the same manner as in Example 1, except that ethanediolic acid was replaced by thioglycolic acid to obtain a hydrofmishing catalyst S8 and a hydrogenation-activated catalyst S8.

[0095] Example 9

[0096] The procedure of Example 1 was followed except that glycolic acid was replaced by malic acid to obtain a hydrorefining catalyst S9 and a hydroactivation catalyst S9.

[0097] Example 10

[0098] The procedure of Example 1 was followed except that glycolic acid was replaced by glycolic acid to obtain a hydrorefining catalyst S10 and a hydroactivation catalyst S10.

[0099] Example 11

[0100] The procedure of Example 1 was followed except that glycolic acid was replaced by aminoacetic acid to obtain a hydrorefining catalyst S11 and a hydroactivation catalyst S11.

[0101] Example 12

[0102] The procedure of Example 1 was followed except that δ-Al203was replaced by γ-Al203to obtain a hydrorefining catalyst S12 and a hydroactivation catalyst S12.

[0103] Comparative Example 1

[0104] The procedure of Example 1 was followed except that glycolic acid was not added and the following procedure was followed:

[0105] (1) 24.52 g of δ-Al203(having a pore volume (BET) of 0.9 mL / g, a pore volume (mercury porosimetry) of 1.1 mL / g, and a specific surface area of 340 m 2 / g), 147.14 g of γ-Al203(having a pore volume (BET) of 1.0 mL / g, a pore volume (mercury porosimetry) of 1.2 mL / g, and a specific surface area of 350 m 2 / g), and 28.34 g of pseudoboehmite were mixed, and 190 g of nitric acid having a concentration of 0.04 wt% was added with stirring to knead at a stirring rate of 30 rpm at 20°C for 0.7 h, followed by extrusion molding, and then dried at 150°C for 2 h and calcined at 500°C for 2 h to obtain a catalyst carrier (in the catalyst carrier, the content of δ-Al203was 12.26 wt%, the content of γ-Al203was 73.57 wt%, and the content of the pseudoboehmite was 14.17 wt%);

[0106] (2) 80 g of nickel nitrate hexahydrate and 100 mL of water were mixed at 15°C for 0.5 h to obtain an impregnation solution, and 100 g of the catalyst carrier was impregnated in the impregnation solution at 15°C for 0.5 h, and then the solid phase was separated by filtration and dried at 150°C for 2 h and calcined at 550°C for 2 h to obtain a hydrorefining catalyst D1;

[0107] (3) The hydrofining catalyst was activated under a hydrogen atmosphere at a hydrogen partial pressure of 3 MPa at 370°C for 6 h at a CS2space velocity of 0.1 h"1, to obtain a hydrogen-activated catalyst D2.

[0108] Comparative Example 2

[0109] (1) 171.62 g of γ-Al2O3 (pore volume (BET) of 1.0 mL / g, pore volume (mercury porosimetry) of 1.2 mL / g, specific surface area of 350 m 2 / g) and 28.34 g of pseudoboehmite were mixed, and 190 g of nitric acid having a concentration of 0.04 wt% was added under stirring, and kneading was performed at a stirring rate of 30 rpm at 20°C for 0.7 h, followed by extrusion molding, and then drying at 150°C for 2 h, and calcination at 500°C for 2 h, to obtain a catalyst carrier (in the catalyst carrier, the content of δ-Al2O3 was 12.26 wt%, the content of γ-Al2O3 was 73.57 wt%, and the content of the pseudoboehmite was 14.17 wt%);

[0110] (2) 80 g of nickel nitrate hexahydrate and 100 mL of water were mixed at 15°C for 0.5 h to obtain an impregnation solution, and 100 g of the catalyst carrier was impregnated in the impregnation solution at 15°C for 0.5 h, and then the solid phase was separated by filtration and dried at 150°C for 2 h, and then calcined at 550°C for 2 h, to obtain a hydrofining catalyst D2;

[0111] (3) The hydrofining catalyst was activated under a hydrogen atmosphere at a hydrogen partial pressure of 3 MPa at 370°C for 6 h at a CS2space velocity of 0.1 h -1 , to obtain a hydrogen-activated catalyst D2.

[0112] Comparative Example 3

[0113] Prepared according to the method of Example 1, except that chloroplatinic acid was used instead of ethylene glycol acid, and the specific preparation steps were as follows:

[0114] (1) 24.52 g of δ-Al2O3 (pore volume (BET) of 0.9 mL / g, pore volume (mercury porosimetry) of 1.1 mL / g, specific surface area of 340 m 2 / g), 147.14 g of γ-Al2O3 (pore volume (BET) of 1.0 mL / g, pore volume (mercury porosimetry) of 1.2 mL / g, specific surface area of 350 m 2(g) and 28.34 g of pseudo-boehmite were mixed, 190 g of nitric acid with a concentration of 0.04 wt% was further added under stirring, kneading was carried out at 20°C for 0.7 h at a stirring rate of 30 rpm, followed by extrusion molding, then drying at 150°C for 2 h, and calcination at 500°C for 2 h, to obtain a catalyst carrier (in the catalyst carrier, the content of δ-Al203was 12.26 wt%, the content of γ-Al203was 73.57 wt%, and the content of the pseudo-boehmite was 14.17 wt%);

[0115] (2) 24.42 g of nickel nitrate hexahydrate, 2.64 g of chloroplatinic acid, and 100 mL of water were mixed at 15°C for 0.5 h to obtain an impregnation solution, 100 g of the catalyst carrier was impregnated in the impregnation solution at 15°C for 0.5 h, then the solid phase was separated by filtration and dried at 150°C for 2 h, and calcined at 550°C for 2 h to obtain a hydrofining catalyst D3;

[0116] (3) The hydrofining catalyst was activated under a hydrogen atmosphere at a hydrogen partial pressure of 3 MPa at 450°C for 6 h to obtain a hydrogen-activated catalyst D3.

[0117] Comparative Example 4

[0118] Prepared according to the method of Example 1, except that ethylene glycol acid was replaced by ammonium metatungstate, and the specific preparation steps were as follows:

[0119] (1) 24.52 g of δ-Al203(having a pore volume (BET) of 0.9 mL / g, a pore volume (mercury porosimetry) of 1.1 mL / g, and a specific surface area of 340 m 2 / g), 147.14 g of γ-Al203(having a pore volume (BET) of 1.0 mL / g, a pore volume (mercury porosimetry) of 1.2 mL / g, and a specific surface area of 350 m 2 / g), and 28.34 g of pseudo-boehmite were mixed, 190 g of nitric acid with a concentration of 0.04 wt% was further added under stirring, kneading was carried out at 20°C for 0.7 h at a stirring rate of 30 rpm, followed by extrusion molding, then drying at 150°C for 2 h, and calcination at 500°C for 2 h, to obtain a catalyst carrier (in the catalyst carrier, the content of δ-Al203was 12.26 wt%, the content of γ-Al203was 73.57 wt%, and the content of the pseudo-boehmite was 14.17 wt%);

[0120] (2) 24.42 g of nickel nitrate hexahydrate, 12.28 g of ammonium metatungstate and 100 mL of water were mixed at 15 °C for 0.5 h to obtain an impregnation solution, 100 g of the catalyst carrier was impregnated in the impregnation solution at 20 °C for 0.6 h, then the solid phase was separated by filtration and dried at 150 °C for 2 h, and then calcined at 550 °C for 2 h to obtain a hydrofining catalyst D4;

[0121] (3) The hydrofining catalyst was activated at 300 °C for 6 h under a hydrogen atmosphere with a hydrogen partial pressure of 3 MPa to obtain a hydrogen-activated catalyst D4.

[0122] Test Example

[0123] (1) The active ingredient content of the hydrofining catalysts prepared in Examples 1-11 was tested, and the content of active metal oxides was recorded in Table 1.

[0124] (2) The BET (specific surface area and pore volume analysis) test was performed on the hydrofining catalysts prepared in Examples 1-11 and Comparative Examples 1-4, and the test method referred to the national standard GB / T 38691-2020. The specific surface area and pore volume measured were recorded in Table 2.

[0125] (3) The pore size distribution test was performed on the hydrofining catalysts prepared in Examples 1-11 and Comparative Examples 1-4, and the test method referred to the national standard GB / T 38691-2020. The pore size distribution was recorded in Table 2.

[0126] (4) The pore volume test was performed on the hydrofining catalysts prepared in Examples 1-11 and Comparative Examples 1-4 by the pressure pump method, and the test method referred to the national standard GB / T 21650.1-2008. The pore volume was recorded in Table 2.

[0127] (5) The X-ray single crystal diffraction (XRD) test was performed on the hydrofining catalysts prepared in Examples 1-11 and Comparative Examples 1-4, and the test method referred to the national standard GB / T 19421.12-2003. The active metal oxide size was recorded in Table 2.

[0128] (6) The activity test was performed on the hydrofining catalysts prepared in Examples 1-11 and Comparative Examples 1-4, using Fischer-Tropsch synthesis oil-based poly-alpha-olefin oil (bromine value: 43 gBr / 100 g) as the raw material for hydrogenation reaction. The test was performed on a 100 mL hydrogenation device, and the reaction conditions were as follows: hydrogen / oil ratio was 400, reaction pressure was 5 MPa, volume space velocity was 0.5 h -1 , reaction temperature was 200 °C. The bromine value and density of the product, as well as the yield and Saybolt color were recorded in Table 3.

[0129] Table 1

[0130] No. Content of active metal oxide (wt%) Example 1 4.23 Example 2 5.91 Example 3 5.91 Example 4 5.91 Example 5 4.23 Example 6 3.12 Example 7 9.64 Example 8 4.23 Example 9 4.23 Example 10 4.23 Example 11 4.23 Example 12 4.23

[0131] Table 2

[0132]

[0133]

[0134] Table 3

[0135]

[0136]

[0137] From the results of Table 2, it can be seen that the γ-Al2O3 and δ-Al2O3 provided by the present application have a large pore volume and pore size, and a higher mesopore and macropore distribution ratio at a certain ratio, and the poly-alpha-olefin hydrorefining catalyst prepared therefrom has excellent catalytic activity. In addition, the specific complexing agent and the ratio of the metal and the complexing agent provided by the present application can effectively control the number of metal active sites and the metal grain size, and can make the metal better dispersed on the catalyst, increase the effective metal content, and reduce the metal loading.

[0138] From the results of Table 3, it can be seen that the hydrogenation catalyst according to the present application has a low bromine value, indicating that the hydrogenation effect of the catalyst is excellent. The product has a high density, indicating that the properties of the product have changed significantly compared to the raw material. The yield is also high, reflecting that the catalyst has fewer side reactions (especially cracking reactions) during hydrogenation, and has stronger hydrogenation capacity, which can reduce the isomerization and hydrogenolysis of the reactants, thereby improving the yield. In addition, the cetane number is also high, meaning that the hydrogenation depth is deep, which can effectively reduce the content of unsaturated olefins, oxygen-containing compounds, etc. in the raw material, and significantly improve the product quality. The catalysts impregnated with different contents and different complexing agents and reduced by low-temperature process have different bromine values, indicating that the dispersion performance of the catalysts for metal elements is different by complexing metal elements with different contents and different complexing agents and reducing and activating in a low-temperature hydrogen atmosphere. In addition, the hydrogenation activity of the catalysts without using a complexing agent to disperse the metal is still poor, although the metal loading is increased, the hydrogenation activity is low.

[0139] The above describes the preferred embodiments of the present application, but the present application is not limited thereto. Within the technical concept of the present application, various simple modifications can be made to the technical solutions of the present application, including combining various technical features in any other suitable manner. These simple modifications and combinations should also be considered as disclosed by the present application, and fall within the protection scope of the present application.

Claims

1. A process for the preparation of a hydrofining catalyst, characterized in that, The method comprises the following steps: (1) kneading, extruding, first drying and calcining alumina and a binder in sequence to obtain a catalyst carrier; (2) impregnating the catalyst carrier in an impregnation solution containing an active metal salt and a complexing agent, then separating the solid phase and performing second drying to obtain a hydrofining catalyst; The complexing agent is at least one selected from ethylenediaminetetraacetic acid, amine trimethylphosphonate, tartaric acid, thioglycolic acid, citric acid, malic acid, glycolic acid, aminoacetic acid and glycolic acid.

2. The method of claim 1, wherein, In step (1), the alumina is at least one selected from γ-Al2O3, δ-Al2O3, η-Al2O3 and α-Al2O3; Preferably, in step (1), the binder is at least one selected from pseudoboehmite, silica sol, alumina sol and water glass; In step (1), the content of the alumina in the catalyst carrier is 60-90 wt%, and the content of the binder is 5-40 wt%.

3. The method according to claim 1 or 2, characterized in that, In step (1), the first drying is performed at a temperature of 100-300 ℃ for 0.5-24 h.

4. The method according to any one of claims 1 to 3, characterized in that, In step (1), the calcining is performed at a temperature of 300-600 ℃ for 0.5-24 h.

5. The method according to any one of claims 1 to 4, characterized in that, In step (2), the active metal salt is at least one selected from salts containing metals of Group VIII and Group VIB; Preferably, the active metal salt is a cobalt salt and / or a nickel salt; Preferably, the active metal salt is nickel nitrate.

6. The method according to any one of claims 1 to 5, characterized in that, The mass ratio of the catalyst carrier to the active metal salt is 1:(0.1-0.4).

7. The method according to any one of claims 1 to 6, characterized in that, In step (2), the molar ratio of the complexing agent to the active metal salt is (0.2-1):

1.

8. The method according to any one of claims 1 to 6, characterized in that, In step (2), the second drying is performed at a temperature of 40-200 ℃ for 0.5-12 h.

9. A hydrofining catalyst prepared by the method of any one of claims 1-8.

10. Use of the hydrofining catalyst of claim 9 in the hydrogenation of poly-alpha-olefin oil.

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