Aromatic hydrocarbon raffinate oil hydrogenation catalyst and preparation method thereof

Abstract

The present application relates to a kind of aromatic hydrocarbon raffinate oil hydrogenation catalyst and its preparation method, the aromatic hydrocarbon raffinate oil hydrogenation includes carrier and active component, carrier is mainly aluminium oxide, with bimodal pore structure, active component includes Pt, Ni, Cu, Ce, Ru, with the mass of catalyst as 100%, Pt content 0.1~0.55%, Ni content 1~6%, Cu content 0.1~1%, Ce content 0.1~0.6%, Ru content 0.01~3%;Wherein active component Ni and Cu are loaded in microemulsion mode, the particle size of microemulsion is greater than the maximum pore size of the small pore of carrier, and less than the maximum pore size of the large pore of carrier;The rest active component is loaded in solution form, and active component Pt is loaded in two steps, first step is to load Pt alone, and second step is to load Ce and Pt simultaneously.The catalyst of the present application has high hydrogenation activity and selectivity, and superior anti-coking performance.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of catalyst preparation, and particularly relates to an aromatic hydrocarbon raffinate hydrogenation catalyst and a preparation method thereof. BACKGROUND

[0002] Aromatic hydrocarbon raffinate is a by-product in the production of aromatic hydrocarbons. Since the octane number of the raffinate is low, the raffinate is not suitable as a blending component of high-grade gasoline. However, the raffinate contains extremely low impurities such as sulfur, nitrogen and heavy metals, and is a high-quality raw material for producing ethylene cracking raw materials and solvent oil. Some production enterprises obtain high-value fine petroleum chemicals from the low-value raffinate through hydrofining and rectification. The raffinate is usually used as a raw material to extract pentane, n-hexane, isohexane, cyclohexane, methylcyclohexane, cyclopentane, n-heptane, 6# and 120# solvent oil and the like. In recent years, the development of the solvent oil industry is very rapid, and the application field is also expanding. Solvent oils of different standards are increasingly widely used in edible oil extraction, adhesive, rubber and the like. The processing of these products has low energy consumption, high utilization value and high profits, and has a broad market prospect. A small amount of olefins and aromatic hydrocarbons in the raffinate seriously affect the properties of the raffinate as solvent oil. Therefore, in order to reasonably utilize the raffinate and give it a higher economic value, the unsaturated hydrocarbons in the raffinate must be removed by hydrofining. The main methods for removing olefins from the raffinate are hydrofining and clay adsorption refining. Since clay is deactivated quickly and the refining effect is unstable, clay is less used in industry. At present, the hydrofining method is mostly used.

[0003] Chinese patent CN107029732B discloses a raffinate oil hydrogenation catalyst and a preparation method. The catalyst uses an alumina carrier with a large pore structure and uses chitosan as a pore expander. The active component is nickel oxide, and contains the auxiliary components tin, lanthanum and magnesium. The catalyst has high activity in raffinate oil aromatic hydrogenation, high impurity resistance and long running period. Chinese patent CN106881124A discloses a catalyst for raffinate oil hydrogenation and a preparation method. The catalyst uses a composite carrier containing zinc oxide-alumina, and the active component is nickel oxide. The catalyst has high activity in raffinate oil aromatic and olefin hydrogenation and is not easy to deactivate, but the catalyst carrier preparation process is complex, which limits its industrial application to some extent. Chinese patent CN106311194A discloses a hydrogenation catalyst preparation method and application for producing edible oil extraction oil. The catalyst uses an impregnation method, the carrier is alumina, the active component is Ni and Pd, and the auxiliary component is K. The catalyst can make the indicators of aromatic raffinate oil after hydrogenation meet the GB 16629-2008 "Vegetable Oil Extraction Solvent" standard, but the long-period running performance of the catalyst is not investigated and explained. Chinese patent CN102773101B provides a preparation method of a solvent oil de-aromatic catalyst. The catalyst carrier is alumina, the active component is NiO, and the auxiliary component is carbonate. The catalyst preparation method is an impregnation method. The catalyst has low cost, simple preparation process and good de-aromatic performance, but the hydrogenation performance of the catalyst on olefins in solvent oil is not mentioned. Chinese patent CN100497540C discloses a hydrogenation refining catalyst. The main active component of the catalyst is Ni, the auxiliary component is Mo, and the carrier is SiO2 modified by Ti. The catalyst is prepared by first preparing a catalyst carrier containing or not containing active metals by a sol-gel method, and then loading the remaining active metals. The catalyst can reduce the content of active components, and improve the resistance to sulfur and nitrogen poisoning, which is suitable for aromatic hydrogenation process, but the removal performance of olefins and long-period running stability are not investigated. Chinese patent CN1132902C introduces a hydrogenation refining catalyst, which uses a porous refractory inorganic oxide as a carrier and a nano metal such as Pd powder as an active component. The catalyst is particularly suitable for post-reforming hydrogenation reaction. It can also be used for solvent oil hydrogenation and other reactions, but the catalyst has high activity for olefin deep hydrogenation, and has no obvious hydrogenation effect on aromatic hydrocarbons. Chinese patent CN104096573B discloses a preparation method of a high anti-coking selective hydrogenation catalyst. The catalyst carrier is mainly alumina and has a bimodal pore distribution structure. It contains double active components Pd and Ni. During the preparation of the catalyst, the anti-coking component Ni enters the large pores of the carrier in the form of a microemulsion. The active component Pd is mainly distributed on the surface of the carrier, especially in the small pores, and the anti-coking component Ni is mainly distributed in the large pores. The catalyst is particularly suitable for carbon two and carbon three fraction hydrogenation, can significantly reduce the amount of green oil and catalyst coking, prolong the service life of the catalyst, and improve the economic benefits of the device operation.CN102600842A discloses an acetic acid hydrogenation catalyst for ethanol, a preparation method and application thereof. The acetic acid hydrogenation catalyst for ethanol comprises an active component and a carrier. The first active component is a group VIII noble metal Pd, Pt, Ru, Rh and a metal oxide M0O3, WO3, CuO, Re2O7. The second active component is one of Zn, Cr, Sn, Co, Ni, Ce, OsO4. The carrier is one of SiO2, Al2O3 and activated carbon. The two-component active metals in the application act as co-catalysts for synergistic catalysis. CN112916022A discloses a selective hydrogenation catalyst, a preparation method and application thereof. The selective hydrogenation catalyst comprises a carrier accounting for 97.5-99.7% of the total mass of the catalyst, 0.1-1.0% of a main catalyst and 0.2-1.5% of an auxiliary catalyst. The carrier is one or two of γ-Al2O3, activated carbon, titanium dioxide and silicon dioxide. The main catalyst is one or more of Rh, Pt, Pd and Ru. The auxiliary catalyst is one or more of Ce, Cu, La, Ni, Fe, Zr, Co and Mn. The existing technology has a single Pt loading mode. The hydrogenation reaction of olefins and aromatic hydrocarbons mainly occurs in the main active center composed of Pt. The macromolecular components produced by the polymerization and other side reactions of olefins and aromatic hydrocarbons in the reaction easily enter the large pores of the catalyst. Pt is prone to aggregation during the reduction process of the catalyst, which affects the catalytic effect.

[0004] For hydrogenation reaction, the hydrogenation catalyst needs to be reduced before application to ensure that the active component exists in the metallic state, so that the catalyst has hydrogenation activity. Because activation is a high-temperature calcination process during catalyst preparation, metal salts are generally decomposed into metal oxides in this process, and the oxides form clusters. Such clusters are generally nanoscale. Different oxides need to be reduced at different temperatures due to their different chemical properties. However, for nanoscale metals, a temperature of about 200°C is an important critical temperature. Above this temperature, metal particles will significantly aggregate. Therefore, how to reduce the aggregation of the main active component during the reduction process and improve the dispersion of the active metal component is of great significance for hydrogenation catalysts. SUMMARY

[0005] In view of the defects of the above-mentioned technology, the purpose of the present application is to provide an aromatic hydrocarbon raffinate hydrogenation catalyst and a preparation method thereof. The prepared catalyst has high dispersion of active components, high activity for deep removal of olefins and aromatic hydrocarbons, good anti-coking performance and good operation stability.

[0006] In order to achieve the above-mentioned purpose, the application provides a preparation method of an aromatic raffinate hydrogenation catalyst, the carrier of the catalyst is mainly alumina, has a bimodal pore structure, contains active components Pt, Ni, Cu, Ce and Ru, the main active component Pt is loaded in two steps, and the preparation of the catalyst comprises the following steps:

[0007] (1) dissolving a soluble precursor of Ni and a soluble precursor of Cu in water, adding an oil phase, a surfactant and a co-surfactant, stirring to form a microemulsion, impregnating a carrier calcined at high temperature in the prepared microemulsion for 0.5-4 hours, filtering out the residual liquid, drying and calcining to obtain a semi-finished catalyst A; the particle size of the microemulsion is greater than the maximum pore size of the small pores of the carrier and less than the maximum pore size of the large pores of the carrier;

[0008] (2) dissolving a soluble precursor of Pt in water to obtain a solution containing Pt, the solution amount is 100-115% of the saturated water absorption amount of the semi-finished catalyst A, the pH is adjusted to 1-3, then the semi-finished catalyst A is added into the solution containing Pt, impregnated and adsorbed for 0.5-4 hours, and then dried and calcined to obtain a semi-finished catalyst B;

[0009] (3) dissolving a soluble precursor of Ce and a soluble precursor of Pt in deionized water to obtain a solution containing Ce and Pt, the solution amount is 100-115% of the saturated water absorption amount of the semi-finished catalyst B, the pH is adjusted to 1-5, then the semi-finished catalyst B is impregnated in the solution containing Ce and Pt, after the solution is completely absorbed, drying and calcining are performed to obtain a semi-finished catalyst C;

[0010] (4) dissolving a precursor salt of Ru in deionized water to obtain a solution containing Ru, the solution amount is 100-115% of the saturated water absorption rate of the semi-finished catalyst C; the semi-finished catalyst C is impregnated in the solution containing Ru, after the solution is completely absorbed, drying and calcining are performed to obtain a final catalyst.

[0011] The surfactant is an ionic surfactant or a non-ionic surfactant, the oil phase is a C6-C8 saturated alkane, the co-surfactant is a C4-C6 alcohol, the weight ratio of the water phase to the oil phase is 1-2.2, the weight ratio of the surfactant to the oil phase is 0.25-0.8, and the weight ratio of the surfactant to the co-surfactant is 1-1.2.

[0012] During the catalyst preparation process, Ni-Cu is impregnated in the form of microemulsion into the macropores of the carrier. The particle size of the microemulsion is larger than the pore size of the small pores of the carrier and smaller than the maximum pore size of the macropores. The Ni-Cu metal salt is contained in the microemulsion and is difficult to enter the small pores of the carrier due to steric hindrance, and thus mainly enters the macropores of the carrier. The remaining active components are impregnated in the form of a solution into the small pores of the carrier. Due to the stronger siphon effect of the small pores, the active components such as Pt loaded in the form of a solution are mainly loaded in the small pores of the catalyst.

[0013] The inventors found that the addition of Ce during the catalyst impregnation process helps to reduce the degree of aggregation of the main active component Pt during the subsequent reduction process of the catalyst. After loading Pt alone and calcining, and then loading Ce and Pt at the same time, the dispersion of the active components is reduced by no more than 20% even after more than 5 times of charring. The reason may be that the metal salt of Ce forms Ce oxide in the form of monolayer distribution after calcination. When Pt is co-loaded with Ce, Pt is mainly loaded on the oxide of Ce, and it is speculated that a Pt 2+ -O 2- -Ce 4+ species is formed. The binding force between the two is much higher than that between Pt and alumina, so the Pt atoms co-loaded with Ce act as a "atomic fence" outside the Pt particles loaded alone, preventing the growth of Pt particles, thereby playing a role in improving the high-temperature agglomeration resistance of Pt active centers and improving the dispersion of the active metal components of the catalyst. In order to make the "atomic fence" formed by Pt and Ce prevent the agglomeration of Pt particles, Pt and Ce are also loaded by the solution method, so that they are mainly located in the small pores of the catalyst.

[0014] Preferably, the step (2) can be performed before the step (1) or after the step (1).

[0015] After the main active component Pt is loaded, Ru is loaded by the solution method, which forms an alloy with Pt to further improve the activity of deep hydrogenation of olefins and aromatics in the raffinate.

[0016] Preferably, the specific surface area of the catalyst carrier is 140-230 m 2 / g, the pore size of the small pores in the bimodal pore structure of the carrier is 5-20 nm, the pore size of the macropores is 30-250 nm, the particle size of the microemulsion is larger than 20 nm and smaller than 250 nm.

[0017] In the present application, the surfactant is an ionic surfactant or a non-ionic surfactant, preferably a non-ionic surfactant, and more preferably polyethylene glycol octyl phenyl ether (Triton X-100) or cetyltrimethylammonium bromide (CTAB); the oil phase is C6-C8 saturated alkane, preferably cyclohexane or n-hexane; and the co-surfactant is C4-C6 alcohol, preferably n-butanol or n-pentanol.

[0018] The carrier in step (1) is mainly alumina, and the alumina content is preferably more than 80 wt%. The crystal form of the alumina is not particularly limited, and the alumina can be γ, θ or a mixture of γ and θ.

[0019] Preferably, the catalyst contains 0.1-0.6 wt% of Ce, and the Pt co-impregnated with the Ce has a content of 0.005-0.05 wt%.

[0020] In the present application, the content of Ce is 0.1-0.6 wt%, and at this content, the Ce can form a single layer of cerium oxide or a discontinuous molecular layer of cerium oxide. The Pt co-impregnated with the Ce has a content of 0.005-0.05 wt% and exists in the form of a single atom, mainly supported on the cerium oxide.

[0021] Preferably, the soluble precursor of Pt is chloroplatinic acid; the soluble precursor of Ni is at least one selected from the group consisting of nickel nitrate hexahydrate, nickel sulfate and nickel chloride; the soluble precursor of Cu is at least one selected from the group consisting of copper sulfate, copper chloride and copper nitrate; the soluble precursor of Ce is at least one selected from the group consisting of cerium chloride and cerium nitrate; and the soluble precursor of Ru is at least one selected from the group consisting of ruthenium trichloride and ammonium chlororuthenate.

[0022] The drying and calcination temperature is not particularly limited in the present application, and the calcination can be performed at 400-600°C for 3-6 hours.

[0023] Preferably, the shape of the carrier is spherical, denticular, cylindrical, trilobal or tetralobal.

[0024] The application also provides an aromatic hydrocarbon raffinate hydrogenation catalyst obtained by the preparation method, comprising a carrier and active components, the carrier is mainly alumina and has a bimodal pore structure, and the active components comprise Pt, Ni, Cu, Ce, and Ru, wherein the content of Pt is 0.1-0.55%, the content of Ni is 1-6%, the content of Cu is 0.1-1%, the content of Ce is 0.1-0.6%, and the content of Ru is 0.01-3%, based on 100% of the mass of the catalyst; the active components of Ni and Cu are loaded in a microemulsion mode, the particle size of the microemulsion is greater than the maximum pore size of the small pores of the carrier and less than the maximum pore size of the large pores of the carrier; the remaining active components are loaded in a solution form, the active component Pt is loaded in two steps, the first step is to load Pt alone, and the second step is to load Ce and Pt simultaneously; the solution method is used to load Ce, Pt, and Ru after the main active component Pt is loaded alone, and the step of loading Ni-Cu in the microemulsion mode is not limited, but to prevent the Ni-Cu from covering the loaded Pt, the step of loading Ni-Cu in the microemulsion mode is preferably performed before the step of loading Pt in the solution method.

[0025] Preferably, the catalyst is characterized in that the content of Pt is 0.2-0.4%, the content of Ni is 2-4%, the content of Cu is 0.3-0.8%, the content of Ce is 0.2-0.45%, and the content of Ru is 0.8-2%, based on 100% of the total weight of the catalyst.

[0026] Preferably, the reduction temperature of the catalyst is 350-450 DEG C.

[0027] The catalyst has the following characteristics: at the beginning of the hydrogenation reaction, the hydrogenation activity of Pt is high, and Pt is mainly distributed in the small pores, so the hydrogenation reaction of olefins and aromatics mainly occurs in the small pores; as the running time of the catalyst is prolonged, a part of the by-products with large molecular weights are generated on the surface of the catalyst, these substances enter the large pores due to the large molecular size and long residence time, and are subjected to hydrogenation reaction under the catalysis of Ni-Cu to generate saturated hydrocarbons, and it is not easy to generate substances with larger molecular weights; after the catalyst is regenerated, the reduction is still at 350-450 DEG C, and the activity of the regenerated catalyst does not change obviously; and the activity of the catalyst does not change obviously after the catalyst is regenerated for about 5 times.

[0028] The application has the following beneficial effects:

[0029] The application selects a carrier with bimodal pore structure and multiple active components, the carrier is mainly alumina and has bimodal pore structure, in the macropore, the Ni-Cu component is loaded, the Ni-Cu has saturated hydrogenation function, while the hydrogenation of the main active component Pt is carried out in cooperation, the saturated hydrogenation reaction of the macromolecular component also occurs in the Ni-Cu active center in the macropore. Because the double bond is saturated by hydrogenation, the macromolecular component cannot occur polymerization reaction or the polymerization reaction rate is greatly reduced, the chain growth reaction is terminated or delayed, and the material is easily carried out of the reactor, so that the coking degree of the surface of the catalyst is greatly reduced, thereby prolonging the service life of the catalyst. The main active component Pt is loaded by a two-step loading method, that is, it is loaded alone first and then loaded with Ce at the same time, so as to improve the dispersion degree of the active metal component of the catalyst. DETAILED DESCRIPTION

[0030] The following detailed description of the embodiments of the application is given on the premise of the technical solutions of the application, and detailed implementation methods and processes are given, but the protection scope of the application is not limited to the following embodiments. The experimental methods not specified in the following embodiments are usually carried out according to conventional conditions.

[0031] The experimental methods in the following embodiments are all conventional methods unless otherwise specified. The reagents and compounds can be obtained by commercial means unless otherwise specified.

[0032] Example 1

[0033] Preparation of the carrier

[0034] A commercially available bimodal pore distribution spherical alumina carrier with a diameter of 3 mm is used. After being calcined at 700 DEG C for 4 h, the bimodal pore size distribution range is 5-15 nm and 30-120 nm, and the specific surface area is 227 m 2 / g. 100 g of the carrier is weighed.

[0035] Preparation of the catalyst

[0036] (1) 24.77 g of nickel nitrate hexahydrate and 0.25 g of copper sulfate are weighed and dissolved in 60 mL of deionized water, 50 g of cyclohexane, 35 g of CTAB and 30 g of n-pentanol are added, and the mixture is fully stirred to form a microemulsion. The prepared carrier is immersed in the prepared microemulsion, shaken for 1 hour, filtered to remove the residual liquid, dried at 100 DEG C for 4 hours, and calcined at 450 DEG C for 3 hours to obtain a semi-finished catalyst A1;

[0037] (2) 0.21 g of chloroplatinic acid is dissolved in deionized water, the solution amount is 110% of the saturated water absorption amount of the semi-finished catalyst A1, the pH is adjusted to 3, and then the semi-finished catalyst A1 is immersed in the prepared solution, dried at 120 DEG C for 4 hours after immersion for 1 hour, and calcined at 500 DEG C for 5 hours to obtain a semi-finished catalyst B1.

[0038] (3) Take chloroplatinic acid 0.105 g, cerium chloride 0.88 g, and dissolve them in deionized water at the same time. The solution amount is 110% of the saturated water absorption amount of the semi-finished catalyst B1, and the pH is adjusted to 2. Then the semi-finished catalyst B1 is immersed in the prepared solution, shaken thoroughly, and dried at 120℃ for 4 hours. After the solution is completely absorbed, the semi-finished catalyst C1 is obtained by calcining at 450℃ for 3 hours.

[0039] (4) Take ruthenium trichloride 2.05 g and dissolve it in deionized water. The solution amount is 110% of the saturated water absorption rate of the semi-finished catalyst C1. Then the semi-finished catalyst C1 is dissolved in the prepared solution, shaken thoroughly, and dried at 120℃ for 4 hours. After the solution is completely absorbed, the final catalyst S1 is obtained by calcining at 400℃ for 6 hours.

[0040] Catalyst reduction:

[0041] The prepared catalyst is loaded into a fixed bed reactor, H2 is introduced at a flow rate of 50 L / h, the system is pressurized to 1.5 MPa, and the catalyst bed is heated to 370℃ at a heating rate of 30℃ / h, then maintained for 10 h to reduce the catalyst. After reduction, the temperature is lowered to the reaction temperature for catalyst performance evaluation.

[0042] Example 2:

[0043] Carrier preparation:

[0044] A commercially available bimodal pore distribution three-leaf clover-shaped alumina carrier with an outer diameter of 3 mm is used. After calcination at 750℃ for 4 h, the bimodal pore size distribution ranges from 6-15 nm and 55-152 nm, and the specific surface area is 202 m 2 / g. Take 100 g of the carrier.

[0045] Catalyst preparation:

[0046] (1) Take chloroplatinic acid 0.63 g and dissolve it in deionized water. The solution amount is 100% of the saturated water absorption amount of the carrier, and the pH is adjusted to 2.5. Then the carrier is immersed in the prepared solution, shaken for 2.5 hours, dried at 120℃ for 4 hours, and calcined at 550℃ for 3 hours to obtain the semi-finished catalyst A2.

[0047] (2) Take nickel sulfate 5.27 g and copper chloride 0.63 g, and dissolve them in 65 mL of deionized water at the same time. Add 50 g of cyclohexane, 38 g of Triton X-100, and 40 g of n-butanol, and stir thoroughly to form a microemulsion. Then the semi-finished catalyst A2 is immersed in the prepared microemulsion, shaken for 0.5 hours, and the remaining liquid is filtered out. After drying at 100℃ for 4 hours, the semi-finished catalyst B2 is obtained by calcining at 550℃ for 5 hours.

[0048] (3) Take chloroplatinic acid 0.0147 g, cerium nitrate 0.58 g, and dissolve them in deionized water at the same time. The solution amount is 150% of the saturated water absorption amount of the semi-finished catalyst B2, and the pH is adjusted to 2.5. Then, the semi-finished catalyst B2 is immersed in the prepared solution, shaken thoroughly, and dried at 120°C for 4 hours. Finally, the semi-finished catalyst C2 is obtained by calcining at 570°C for 5 hours.

[0049] (4) Take ammonium chlororuthenate 6.92 g and dissolve it in deionized water. The solution amount is 110% of the saturated water absorption rate of the semi-finished catalyst C2. Then, the semi-finished catalyst C2 is dissolved in the prepared solution, shaken thoroughly, and dried at 120°C for 4 hours. Finally, the final catalyst S2 is obtained by calcining at 550°C for 3 hours.

[0050] Catalyst reduction:

[0051] The prepared catalyst is loaded into a fixed bed reactor. H2 is introduced at a flow rate of 50 L / h, and the system is pressurized to 1.5 MPa. The catalyst bed is heated to 400°C at a heating rate of 30°C / h, and then maintained for 10 h to reduce the catalyst. After reduction, the temperature is lowered to the reaction temperature for catalyst performance evaluation.

[0052] Example 3:

[0053] Carrier preparation:

[0054] A commercially available bimodal pore distribution tooth-shaped alumina carrier with a diameter of 3 mm is used. After calcination at 770°C for 4 h, the bimodal pore size distribution ranges from 6 to 16 nm and 69 to 173 nm, and the specific surface area is 189 m 2 / g. Take 100 g of the carrier.

[0055] Catalyst preparation:

[0056] (1) Take nickel nitrate hexahydrate 17.34 g and copper nitrate 1.77 g, and dissolve them in 70 mL of deionized water at the same time. Add 50 g of n-hexane, 30 g of CTAB, and 25 g of n-pentanol, and stir thoroughly to form a microemulsion. Immerse the prepared carrier into the prepared microemulsion and shake for 2 hours. Filter out the remaining liquid, dry at 100°C for 4 hours, and calcine at 470°C for 4 hours to obtain the semi-finished catalyst A3.

[0057] (2) Take chloroplatinic acid 0.84 g and dissolve it in deionized water. The solution amount is 110% of the saturated water absorption amount of the semi-finished catalyst A3, and the pH is adjusted to 1.5. Then, the semi-finished catalyst A3 is immersed in the prepared solution, shaken for 3.5 hours, and dried at 120°C for 4 hours. Finally, the semi-finished catalyst B3 is obtained by calcining at 450°C for 4 hours.

[0058] (3) Take chloroplatinic acid 0.042 g, cerium nitrate 0.77 g, and dissolve them in deionized water at the same time. The solution amount is 110% of the saturated water absorption amount of the semi-finished catalyst B3, and the pH is adjusted to 1.5. Then, the semi-finished catalyst B3 is immersed in the prepared solution, shaken thoroughly, and dried at 120°C for 4 hours. Finally, the semi-finished catalyst C3 is obtained by calcining at 500°C for 3.5 hours.

[0059] (4) Take ruthenium trichloride 4.93 g and dissolve it in deionized water. The solution amount is 110% of the saturated water absorption rate of the semi-finished catalyst C3. Then, the semi-finished catalyst C3 is dissolved in the prepared solution, shaken thoroughly, and dried at 120°C for 4 hours. Finally, the final catalyst S3 is obtained by calcining at 460°C for 4.5 hours.

[0060] Catalyst reduction:

[0061] The prepared catalyst is loaded into a fixed bed reactor. H2 is introduced at a flow rate of 50 L / h, and the system is pressurized to 1.5 MPa. The catalyst bed is heated to 430°C at a heating rate of 30°C / h, and then maintained for 10 h to reduce the catalyst. After reduction, the temperature is lowered to the reaction temperature for catalyst performance evaluation.

[0062] Example 4:

[0063] Carrier preparation:

[0064] A commercially available bimodal pore distribution cylindrical alumina carrier with a diameter of 3.5 mm and a length of 5 mm is used. After calcination at 800°C for 4 h, the bimodal pore size distribution ranges from 8 to 17 nm and 87 to 188 nm, and the specific surface area is 180 m 2 / g. Take 100 g of the carrier.

[0065] Catalyst preparation:

[0066] (1) Take nickel chloride 2.21 g and copper sulfate 0.5 g, and dissolve them in 60 mL of deionized water at the same time. Add 40 g of cyclohexane, 25 g of Triton X-100, and 22 g of n-butanol, and stir thoroughly to form a microemulsion. Immerse the prepared carrier into the prepared microemulsion and shake for 3 hours. Filter out the remaining liquid, dry at 100°C for 4 hours, and calcine at 600°C for 4.5 hours to obtain the semi-finished catalyst A4.

[0067] (2) Take chloroplatinic acid 0.63 g and dissolve it in deionized water. The solution amount is 110% of the saturated water absorption amount of the semi-finished catalyst A4, and the pH is adjusted to 1. Then, the semi-finished catalyst A4 is immersed in the prepared solution, shaken for 3 hours, dried at 120°C for 4 hours, and calcined at 520°C for 5 hours to obtain the semi-finished catalyst B4.

[0068] (3) Take chloroplatinic acid 0.021 g, cerium chloride 0.18 g, and dissolve them in deionized water at the same time. The solution amount is 110% of the saturated water absorption amount of the semi-finished catalyst B4, and the pH is adjusted to 4. Then, the semi-finished catalyst B4 is immersed in the prepared solution, shaken thoroughly, and dried at 120°C for 4 hours. Finally, the semi-finished catalyst C4 is obtained by calcining at 400°C for 4.5 hours.

[0069] (4) Take ruthenium trichloride 2.46 g and dissolve it in deionized water. The solution amount is 110% of the saturated water absorption rate of the semi-finished catalyst C4. Then, the semi-finished catalyst C4 is dissolved in the prepared solution, shaken thoroughly, and dried at 120°C for 4 hours. Finally, the final catalyst S4 is obtained by calcining at 570°C for 4 hours.

[0070] Catalyst reduction:

[0071] The prepared catalyst is loaded into a fixed bed reactor. H2 is introduced at a flow rate of 50 L / h, and the system is pressurized to 1.5 MPa. The catalyst bed is heated to 390°C at a heating rate of 30°C / h, and then maintained for 10 h to reduce the catalyst. After reduction, the temperature is lowered to the reaction temperature for catalyst performance evaluation.

[0072] Example 5:

[0073] Carrier preparation:

[0074] A commercially available bimodal pore distribution spherical alumina carrier with a diameter of 2.5 mm is used. After calcination at 850°C for 4 h, the bimodal pore size distribution ranges from 8 to 19 nm and 113 to 211 nm, and the specific surface area is 158 m 2 / g. Take 100 g of the carrier.

[0075] Catalyst preparation:

[0076] (1) Take nickel sulfate 10.55 g and copper nitrate 2.66 g, and dissolve them in 65 mL of deionized water at the same time. Add 40 g of n-hexane, 20 g of CTAB, and 18 g of n-butanol, and stir thoroughly to form a microemulsion. Immerse the prepared carrier into the prepared microemulsion and shake for 2.5 hours. Filter out the remaining liquid, dry at 100°C for 4 hours, and calcine at 420°C for 3.5 hours to obtain the semi-finished catalyst A5.

[0077] (2) Take chloroplatinic acid 0.21 g and dissolve it in deionized water. The solution amount is 110% of the saturated water absorption amount of the semi-finished catalyst A5, and the pH is adjusted to 2. Then, the semi-finished catalyst A5 is immersed in the prepared solution, dried at 120°C for 4 hours after 2 hours of immersion, and calcined at 400°C for 6 hours to obtain the semi-finished catalyst B5.

[0078] (3) take chloroplatinic acid 0.0315g, cerium nitrate 1.4g, dissolved in deionized water at the same time, the solution amount is 110% of the saturated water absorption of semi-finished catalyst B5, adjust the pH to 5, then immerse the semi-finished catalyst B5 into the prepared solution, shake thoroughly, and dry at 120°C for 4 hours, then calcine at 550°C for 6 hours to obtain semi-finished catalyst C5.

[0079] (4) take ruthenium trichloride 1.03g dissolved in deionized water, the solution amount is 110% of the saturated water absorption of semi-finished catalyst C5; dissolve the semi-finished catalyst C5 in the prepared solution, shake thoroughly, and dry at 120°C for 4 hours, then calcine at 600°C for 5 hours to obtain the final catalyst S5.

[0080] Catalyst reduction:

[0081] Put the prepared catalyst into a fixed bed reactor, introduce H2 at a flow rate of 50L / h, pressurize the system to 1.5MPa, heat the catalyst bed to 350°C at a heating rate of 30°C / h, and then maintain for 10h to reduce the catalyst. After reduction, cool to the reaction temperature for catalyst performance evaluation.

[0082] Example 6:

[0083] Preparation of the carrier:

[0084] A commercially available bimodal pore distribution trilobal strip-shaped alumina carrier with an outer diameter of 2.5mm is used. After calcination at 870°C for 4h, the bimodal pore size distribution ranges from 9nm to 20nm and 126nm to 223nm, and the specific surface area is 151m 2 / g. Take 100g of the carrier.

[0085] Preparation of the catalyst:

[0086] (1) take nickel nitrate hexahydrate 29.73g, copper chloride 2.12g, and dissolve them in 75mL of deionized water at the same time, add 40g of cyclohexane, 15g of CTAB, and 14g of n-pentanol, and stir thoroughly to form a microemulsion, immerse the prepared carrier into the prepared microemulsion, shake for 4 hours, filter out the remaining liquid, dry at 100°C for 4 hours, and calcine at 530°C for 5.5 hours to obtain semi-finished catalyst A6;

[0087] (2) take chloroplatinic acid 0.35g dissolved in deionized water, the solution amount is 110% of the saturated water absorption of semi-finished catalyst A6, adjust the pH to 3, then immerse the semi-finished catalyst A6 into the prepared solution, immerse for 4 hours, dry at 120°C for 4 hours, and calcine at 600°C for 4 hours to obtain semi-finished catalyst B6.

[0088] (3) Take chloroplatinic acid 0.063 g, cerium nitrate 1.05 g, and dissolve them in deionized water at the same time. The solution amount is 110% of the saturated water absorption amount of the semi-finished catalyst B6, and the pH is adjusted to 3.5. Then, the semi-finished catalyst B6 is immersed in the prepared solution, shaken thoroughly, and dried at 120°C for 4 hours. Finally, the semi-finished catalyst C6 is obtained by calcining at 420°C for 4 hours.

[0089] (4) Take ruthenium trichloride 0.02 g and dissolve it in deionized water. The solution amount is 110% of the saturated water absorption rate of the semi-finished catalyst C6. Then, the semi-finished catalyst C6 is dissolved in the prepared solution, shaken thoroughly, and dried at 120°C for 4 hours. Finally, the final catalyst S6 is obtained by calcining at 600°C for 5 hours.

[0090] Catalyst reduction:

[0091] The prepared catalyst is loaded into a fixed bed reactor. H2 is introduced at a flow rate of 50 L / h, and the system is pressurized to 1.5 MPa. The catalyst bed is heated to 450°C at a heating rate of 30°C / h, and then maintained for 10 h to reduce the catalyst. After reduction, the temperature is lowered to the reaction temperature for catalyst performance evaluation.

[0092] Example 7

[0093] Carrier preparation:

[0094] A commercially available bimodal pore distribution tooth-shaped alumina carrier with a diameter of 2.5 mm is used. After calcination at 900°C for 4 h, the bimodal pore size distribution ranges from 10 to 20 nm and 152 to 250 nm, and the specific surface area is 142 m 2 / g. Take 100 g of the carrier.

[0095] Catalyst preparation:

[0096] (1) Take nickel chloride 6.62 g and copper sulfate 1.76 g, and dissolve them in 82 mL of deionized water at the same time. Add 38 g of n-hexane, 10 g of CTAB, and 10 g of n-pentanol, and stir thoroughly to form a microemulsion. Immerse the prepared carrier into the prepared microemulsion and shake for 3.5 hours. Filter out the remaining liquid, dry at 100°C for 4 hours, and calcine at 400°C for 6 hours to obtain the semi-finished catalyst A7.

[0097] (2) Take chloroplatinic acid 1.05 g and dissolve it in deionized water. The solution amount is 110% of the saturated water absorption amount of the semi-finished catalyst A7, and the pH is adjusted to 2. Then, the semi-finished catalyst A7 is immersed in the prepared solution, and dried at 120°C for 4 hours after 0.5 hours of immersion. Finally, the semi-finished catalyst B7 is obtained by calcining at 490°C for 3 hours.

[0098] (3) Take 0.0863 g of platinum chloride and 0.97 g of cerium chloride, and dissolve them in deionized water. The solution amount is 110% of the saturated water absorption amount of the semi-finished catalyst B7, and the pH is adjusted to 1. Then, the semi-finished catalyst B7 is immersed in the prepared solution, shaken thoroughly, and dried at 120°C for 4 hours. After the solution is completely absorbed, the semi-finished catalyst C7 is obtained by calcining at 520°C for 5.5 hours.

[0099] (4) Take 10.38 g of ammonium chlororuthenate and dissolve it in deionized water. The solution amount is 110% of the saturated water absorption rate of the semi-finished catalyst C7. Then, the semi-finished catalyst C7 is dissolved in the prepared solution, shaken thoroughly, and dried at 120°C for 4 hours. After the solution is completely absorbed, the final catalyst S7 is obtained by calcining at 500°C for 3.5 hours.

[0100] Catalyst reduction:

[0101] The prepared catalyst is loaded into a fixed bed reactor, H2 is introduced at a flow rate of 50 L / h, the system is pressurized to 1.5 MPa, and the catalyst bed is heated to 410°C at a heating rate of 30°C / h, then maintained for 10 h to reduce the catalyst. After reduction, the temperature is lowered to the reaction temperature for catalyst performance evaluation.

[0102] Comparative Example 1:

[0103] The same carrier as in Example 1 is used, and the catalyst preparation conditions are the same as in Example 1, except that the step of co-loading Pt and Ce is omitted.

[0104] Carrier preparation:

[0105] A commercially available bimodal pore distribution spherical alumina carrier with a diameter of 3 mm is used. After calcination at 700°C for 4 h, the bimodal pore size distribution ranges from 5-15 nm and 30-120 nm, and the specific surface area is 227 m 2 / g. Take 100 g of the carrier.

[0106] Catalyst preparation:

[0107] (1) Take 24.77 g of nickel nitrate hexahydrate and 0.25 g of copper sulfate, and dissolve them in 60 mL of deionized water. Add 50 g of cyclohexane, 35 g of CTAB, and 30 g of n-pentanol, and stir thoroughly to form a microemulsion. Immerse the prepared carrier in the prepared microemulsion and shake for 1 hour. Filter out the remaining liquid, dry at 100°C for 4 hours, and calcine at 450°C for 3 hours to obtain the semi-finished catalyst DA1.

[0108] (2) take chloroplatinic acid 0.21 g dissolved in deionized water, the solution amount is 110% of the saturated water absorption of semi-finished catalyst DA1, adjust pH to 3, then immerse semi-finished catalyst DA1 into the prepared solution, dry at 120℃ for 4 hours after 1 hour of immersion, calcine at 500℃ for 5 hours, to obtain semi-finished catalyst DB1.

[0109] (3) take ruthenium trichloride 2.05 g dissolved in deionized water, the solution amount is 110% of the saturated water absorption of semi-finished catalyst DB1, then immerse semi-finished catalyst DB1 into the prepared solution, shake thoroughly, dry at 120℃ for 4 hours, calcine at 400℃ for 6 hours, to obtain final catalyst D1.

[0110] Catalyst reduction:

[0111] Put the prepared catalyst into a fixed bed reactor, introduce H2 at a flow rate of 50 L / h, pressurize the system to 1.5 MPa, heat the catalyst bed to 370℃ at a heating rate of 30℃ / h, then maintain for 10 h to reduce the catalyst. After reduction, cool down to the reaction temperature for catalyst performance evaluation.

[0112] Comparative Example 2:

[0113] Use the same carrier as in Example 1, and the catalyst preparation conditions are the same as in Example 1, the difference is that only Ce is loaded in this step of Pt and Ce co-loading.

[0114] Carrier preparation:

[0115] Use commercially available bimodal pore size distribution spherical alumina carrier, diameter is 3 mm. After calcination at 700℃ for 4 h, the bimodal pore size distribution range is 5-15 nm and 30-120 nm, the specific surface area is 227 m 2 / g. Take 100 g of the carrier.

[0116] Catalyst preparation:

[0117] (1) take nickel nitrate hexahydrate 24.77 g and copper sulfate 0.25 g, dissolve in 60 mL deionized water at the same time, add cyclohexane 50 g, CTAB 35 g, n-pentanol 30 g, and stir thoroughly to form a microemulsion, immerse the prepared carrier into the prepared microemulsion, shake for 1 hour, filter out the remaining liquid, dry at 100℃ for 4 hours, calcine at 450℃ for 3 hours, to obtain semi-finished catalyst DA2;

[0118] (2) take chloroplatinic acid 0.21 g dissolved in deionized water, the solution amount is 110% of the saturated water absorption of semi-finished catalyst DA2, adjust pH to 3, then immerse semi-finished catalyst DA2 into the prepared solution, dry at 120℃ for 4 hours after 1 hour of immersion, calcine at 500℃ for 5 hours, to obtain semi-finished catalyst DB2.

[0119] (3) Weigh 0.88g of cerium chloride and dissolve it in deionized water. The solution volume is 110% of the saturated water absorption capacity of the semi-finished catalyst DB2. Adjust the pH to 2, then immerse the semi-finished catalyst DB2 in the prepared solution, shake it thoroughly, and wait for the solution to be completely absorbed. Dry it at 120℃ for 4 hours and calcine it at 450℃ for 3 hours to obtain the semi-finished catalyst DC2.

[0120] (4) Weigh 2.05g of ruthenium trichloride and dissolve it in deionized water. The solution volume is 110% of the saturated water absorption rate of the semi-finished catalyst DC2. Dissolve the semi-finished catalyst DC2 in the prepared solution, shake it thoroughly, and wait for the solution to be completely absorbed. Dry it at 120℃ for 4 hours and calcine it at 400℃ for 6 hours to obtain the final catalyst D2.

[0121] Catalyst reduction:

[0122] The prepared catalyst was loaded into a fixed-bed reactor, and H2 was introduced at a flow rate of 50 L / h. The system was pressurized to 1.5 MPa, and the catalyst bed was heated to 370 °C at a heating rate of 30 °C / h and maintained for 10 h to reduce the catalyst. After reduction, the temperature was lowered to the reaction temperature for catalyst performance evaluation.

[0123] Comparative Example 3:

[0124] Using the same support as in Example 3, and with the same catalyst preparation conditions as in Example 3, the difference was that the solution loading step of the promoter Ru was placed before the solution loading step of the main active component Pt alone.

[0125] Carrier preparation:

[0126] A commercially available bimodal pore-distribution spherical alumina carrier with a diameter of 3 mm was used. After calcination at 770℃ for 4 hours, the bimodal pore size distribution ranged from 6 to 16 nm and from 69 to 173 nm, with a specific surface area of ​​189 m². 2 / g. Weigh 100g of the carrier.

[0127] Catalyst preparation:

[0128] (1) Weigh 17.34 g of nickel nitrate hexahydrate and 1.77 g of copper nitrate, dissolve them in 70 mL of deionized water, add 50 g of n-hexane, 30 g of CTAB and 25 g of n-pentanol, stir thoroughly to form a microemulsion, immerse the prepared carrier in the prepared microemulsion, shake for 2 hours, filter out the residual liquid, dry at 100 °C for 4 hours, calcine at 470 °C for 4 hours to obtain the semi-finished catalyst DA3;

[0129] (2) Take 4.93 g of ruthenium trichloride and dissolve it in deionized water, and the solution amount is 110% of the saturated water absorption of the semi-finished catalyst DA3; dissolve the semi-finished catalyst DA3 in the prepared solution, shake thoroughly, and dry at 120°C for 4 hours after the solution is completely absorbed, and then calcine at 460°C for 4.5 hours to obtain the semi-finished catalyst DB3.

[0130] (3) Take 0.84 g of chloroplatinic acid and dissolve it in deionized water, and the solution amount is 110% of the saturated water absorption of the semi-finished catalyst DB3, and the pH is adjusted to 1.5; then immerse the semi-finished catalyst DB3 in the prepared solution, and dry at 120°C for 4 hours after being immersed for 3.5 hours, and then calcine at 450°C for 4 hours to obtain the semi-finished catalyst DC3.

[0131] (4) Take 0.042 g of chloroplatinic acid and 0.77 g of cerium nitrate, and dissolve them in deionized water at the same time, and the solution amount is 110% of the saturated water absorption of the semi-finished catalyst DC3, and the pH is adjusted to 1.5; then immerse the semi-finished catalyst DC3 in the prepared solution, shake thoroughly, and dry at 120°C for 4 hours after the solution is completely absorbed, and then calcine at 500°C for 3.5 hours to obtain the final catalyst D3.

[0132] Catalyst reduction:

[0133] Put the prepared catalyst into a fixed bed reactor, introduce H2 at a flow rate of 50 L / h, pressurize the system to 1.5 MPa, heat the catalyst bed to 430°C at a heating rate of 30°C / h, and then maintain the temperature for 10 h to reduce the catalyst. After reduction, cool to the reaction temperature for catalyst performance evaluation.

[0134] Comparative Example 4:

[0135] The catalyst preparation conditions are the same as those in Example 3, except that the catalyst carrier is a single-peak pore distribution.

[0136] Carrier preparation:

[0137] A commercially available single-peak pore distribution tooth-shaped alumina carrier with a diameter of 3 mm is used. After calcination at 770°C for 4 h, the pore size distribution range is 52-168 nm, and the specific surface area is 185 m 2 / g. Take 100 g of the carrier.

[0138] Catalyst preparation:

[0139] (1) Take 17.34 g of nickel nitrate hexahydrate and 1.77 g of copper nitrate, and dissolve them in 70 mL of deionized water, add 50 g of n-hexane, 30 g of CTAB, and 25 g of n-pentanol, and fully stir to form a microemulsion. Dip the prepared carrier into the prepared microemulsion, shake for 2 hours, filter out the remaining liquid, dry at 100°C for 4 hours, and calcine at 470°C for 4 hours to obtain a semi-finished catalyst DA4.

[0140] (2) Take 0.84 g of chloroplatinic acid and dissolve it in deionized water, and the solution amount is 110% of the saturated water absorption amount of the semi-finished catalyst DA4, and the pH is adjusted to 1.5. Then dip the semi-finished catalyst DA4 into the prepared solution, and after 3.5 hours of immersion, dry at 120°C for 4 hours, and calcine at 450°C for 4 hours to obtain a semi-finished catalyst DB4.

[0141] (3) Take 0.042 g of chloroplatinic acid and 0.77 g of cerium nitrate, and dissolve them in deionized water, and the solution amount is 110% of the saturated water absorption amount of the semi-finished catalyst DB4, and the pH is adjusted to 1.5. Then dip the semi-finished catalyst DB4 into the prepared solution, fully shake, and after the solution is fully absorbed, dry at 120°C for 4 hours, and calcine at 500°C for 3.5 hours to obtain a semi-finished catalyst DC4.

[0142] (4) Take 4.93 g of ruthenium trichloride and dissolve it in deionized water, and the solution amount is 110% of the saturated water absorption rate of the semi-finished catalyst DC4. Dip the semi-finished catalyst DC4 into the prepared solution, fully shake, and after the solution is fully absorbed, dry at 120°C for 4 hours, and calcine at 460°C for 4.5 hours to obtain the final catalyst D4.

[0143] Catalyst reduction:

[0144] Put the prepared catalyst into a fixed bed reactor, introduce H2 at a flow rate of 50 L / h, pressurize the system to 1.5 MPa, heat the catalyst bed to 430°C at a heating rate of 30°C / h, and maintain the temperature for 10 h to reduce the catalyst. After reduction, cool to the reaction temperature for catalyst performance evaluation.

[0145] Comparative Example 5:

[0146] Use the same carrier as in Example 4, and the catalyst preparation conditions are the same as in Example 4, except that the step of loading Ni-Cu by microemulsion method is cancelled.

[0147] Carrier preparation:

[0148] A commercially available bimodal pore distribution cylindrical alumina carrier with a diameter of 3.5 mm and a length of 5 mm is used. After calcination at 800°C for 4 h, the bimodal pore size distribution ranges from 8 nm to 17 nm and 87 nm to 188 nm, and the specific surface area is 180 m 2 / g. Take 100 g of the carrier.

[0149] Catalyst preparation:

[0150] (1) Take 0.63 g of chloroplatinic acid and dissolve it in deionized water, the solution amount is 110% of the saturated water absorption amount of the carrier, adjust the pH to 1, then immerse the carrier into the prepared solution, after 3 hours of immersion, dry at 120°C for 4 hours, and calcine at 520°C for 5 hours to obtain the semi-finished catalyst DA5.

[0151] (2) Take 0.021 g of chloroplatinic acid and 0.18 g of cerium chloride, and dissolve them in deionized water at the same time, the solution amount is 110% of the saturated water absorption amount of the semi-finished catalyst DA5, adjust the pH to 4, then immerse the semi-finished catalyst DA5 into the prepared solution, shake thoroughly, dry at 120°C for 4 hours after the solution is completely absorbed, and calcine at 400°C for 4.5 hours to obtain the semi-finished catalyst DB5.

[0152] (3) Take 2.46 g of ruthenium trichloride and dissolve it in deionized water, the solution amount is 110% of the saturated water absorption rate of the semi-finished catalyst DB5, then dissolve the semi-finished catalyst DB5 in the prepared solution, shake thoroughly, dry at 120°C for 4 hours after the solution is completely absorbed, and calcine at 570°C for 4 hours to obtain the final catalyst D5.

[0153] Catalyst reduction:

[0154] The prepared catalyst is loaded into a fixed bed reactor, H2 is introduced at a flow rate of 50 L / h, the system is pressurized to 1.5 MPa, the catalyst bed is heated to 390°C at a heating rate of 30°C / h, and then maintained for 10 h to reduce the catalyst. After reduction, the temperature is lowered to the reaction temperature for catalyst performance evaluation.

[0155] Comparative Example 6:

[0156] The same carrier as in Example 5 is used, and the catalyst preparation conditions are the same as in Example 5, except that only Ni is loaded in the step of loading Ni-Cu by microemulsion method.

[0157] Carrier preparation:

[0158] A commercially available bimodal pore size distribution spherical alumina carrier with a diameter of 2.5 mm is used. After calcination at 850°C for 4 h, the bimodal pore size distribution ranges from 8 nm to 19 nm and 113 nm to 211 nm, and the specific surface area is 158 m 2 / g. Take 100 g of the carrier.

[0159] Catalyst preparation:

[0160] (1) Weigh 10.55 g of nickel sulfate into 65 mL of deionized water, add 40 g of n-hexane, 20 g of CTAB, and 18 g of n-butanol, and stir thoroughly to form a microemulsion. Immerse the prepared carrier into the prepared microemulsion, shake for 2.5 hours, filter out the remaining liquid, dry at 100°C for 4 hours, and calcine at 420°C for 3.5 hours to obtain a semi-finished catalyst DA6.

[0161] (2) Weigh 0.21 g of chloroplatinic acid into deionized water, and adjust the solution to 110% of the saturated water absorption of the semi-finished catalyst DA6, and adjust the pH to 2. Then immerse the semi-finished catalyst DA6 into the prepared solution, and dry at 120°C for 4 hours after 2 hours of immersion. Finally, calcine at 400°C for 6 hours to obtain a semi-finished catalyst DB6.

[0162] (3) Weigh 0.0315 g of chloroplatinic acid and 1.4 g of cerium nitrate into deionized water, and adjust the solution to 110% of the saturated water absorption of the semi-finished catalyst DB6, and adjust the pH to 5. Then immerse the semi-finished catalyst DB6 into the prepared solution, shake thoroughly, and dry at 120°C for 4 hours. Finally, calcine at 550°C for 6 hours to obtain a semi-finished catalyst DC6.

[0163] (4) Weigh 1.03 g of ruthenium trichloride into deionized water, and adjust the solution to 110% of the saturated water absorption of the semi-finished catalyst DC6. Then immerse the semi-finished catalyst DC6 into the prepared solution, shake thoroughly, and dry at 120°C for 4 hours. Finally, calcine at 600°C for 5 hours to obtain a final catalyst D6.

[0164] Catalyst reduction:

[0165] Load the prepared catalyst into a fixed bed reactor, introduce H2 at a flow rate of 50 L / h, pressurize the system to 1.5 MPa, heat the catalyst bed to 350°C at a heating rate of 30°C / h, and maintain the temperature for 10 h to reduce the catalyst. After reduction, cool the catalyst to the reaction temperature for catalyst performance evaluation.

[0166] Comparative Example 7:

[0167] Use the same carrier as in Example 5, and the same catalyst preparation conditions as in Example 5, except that only Cu is loaded in the step of loading Ni-Cu by the microemulsion method.

[0168] Carrier preparation:

[0169] Use a commercially available bimodal pore distribution spherical alumina carrier with a diameter of 2.5 mm. After calcination at 850°C for 4 h, the bimodal pore size distribution ranges from 8 nm to 19 nm and 113 nm to 211 nm, and the specific surface area is 158 m 2 / g. Weigh 100 g of the carrier.

[0170] Catalyst preparation:

[0171] (1) Weigh 2.66 g of copper nitrate into 65 mL of deionized water, add 40 g of n-hexane, 20 g of CTAB, and 18 g of n-butanol, and stir thoroughly to form a microemulsion. Immerse the prepared carrier into the prepared microemulsion, shake for 2.5 hours, filter out the remaining liquid, dry at 100°C for 4 hours, and calcine at 420°C for 3.5 hours to obtain a semi-finished catalyst DA7.

[0172] (2) Weigh 0.21 g of chloroplatinic acid into deionized water, and the solution volume is 110% of the saturated water absorption of the semi-finished catalyst DA7. Adjust the pH to 2, immerse the semi-finished catalyst DA7 into the prepared solution, and dry at 120°C for 4 hours after 2 hours of immersion. Calcine at 400°C for 6 hours to obtain a semi-finished catalyst DB7.

[0173] (3) Weigh 0.0315 g of chloroplatinic acid and 1.4 g of cerium nitrate into deionized water, and the solution volume is 110% of the saturated water absorption of the semi-finished catalyst DB7. Adjust the pH to 5, immerse the semi-finished catalyst DB7 into the prepared solution, and dry at 120°C for 4 hours after thorough shaking until the solution is completely absorbed. Calcine at 550°C for 6 hours to obtain a semi-finished catalyst DC7.

[0174] (4) Weigh 1.03 g of ruthenium trichloride into deionized water, and the solution volume is 110% of the saturated water absorption of the semi-finished catalyst DC7. Immerse the semi-finished catalyst DC7 into the prepared solution, and dry at 120°C for 4 hours after thorough shaking until the solution is completely absorbed. Calcine at 600°C for 5 hours to obtain the final catalyst D7.

[0175] Catalyst reduction:

[0176] Load the prepared catalyst into a fixed bed reactor, introduce H2 at a flow rate of 50 L / h, pressurize the system to 1.5 MPa, heat the catalyst bed to 350°C at a heating rate of 30°C / h, and maintain the temperature for 10 h to reduce the catalyst. After reduction, cool the system to the reaction temperature for catalyst performance evaluation.

[0177] Comparative Example 8:

[0178] Use the same carrier as in Example 6, except that the solution method is used for the Ni-Cu loading step, and other preparation conditions are the same as in Example 6.

[0179] Carrier preparation:

[0180] Use a commercially available bimodal pore distribution clover-shaped strip-shaped alumina carrier with an outer diameter of 2.5 mm. After calcination at 870°C for 4 h, the bimodal pore size distribution ranges from 9 nm to 20 nm and 126 nm to 223 nm, and the specific surface area is 151 m2 / g. The carrier 100 g was weighed.

[0181] Catalyst preparation:

[0182] (1) 29.73 g of nickel nitrate hexahydrate and 2.12 g of copper chloride were weighed and dissolved in deionized water, and the solution was prepared to 110% of the saturated water absorption amount of the carrier. The prepared carrier was immersed in the prepared solution, dried at 100°C for 4 hours after 4 hours of immersion, calcined at 530°C for 5.5 hours, and a semi-finished catalyst DA8 was obtained.

[0183] (2) 0.35 g of chloroplatinic acid was weighed and dissolved in deionized water, and the solution was prepared to 110% of the saturated water absorption amount of the semi-finished catalyst DA8. The pH was adjusted to 3, and then the semi-finished catalyst DA8 was immersed in the prepared solution. After 4 hours of immersion, the catalyst was dried at 120°C for 4 hours and calcined at 600°C for 4 hours to obtain a semi-finished catalyst DB8.

[0184] (3) 0.063 g of chloroplatinic acid and 1.05 g of cerium nitrate were weighed and dissolved in deionized water, and the solution was prepared to 110% of the saturated water absorption amount of the semi-finished catalyst DB8. The pH was adjusted to 3.5, and then the semi-finished catalyst DB8 was immersed in the prepared solution. After sufficient shaking, the solution was completely absorbed, and the catalyst was dried at 120°C for 4 hours and calcined at 420°C for 4 hours to obtain a semi-finished catalyst DC8.

[0185] (4) 0.02 g of ruthenium trichloride was weighed and dissolved in deionized water, and the solution was prepared to 110% of the saturated water absorption rate of the semi-finished catalyst DC8. The semi-finished catalyst DC8 was dissolved in the prepared solution, and after sufficient shaking, the solution was completely absorbed. The catalyst was dried at 120°C for 4 hours and calcined at 600°C for 5 hours to obtain a final catalyst D8.

[0186] Catalyst reduction:

[0187] The prepared catalyst was loaded into a fixed bed reactor, H2 was introduced at a flow rate of 50 L / h, the system was pressurized to 1.5 MPa, and the catalyst bed was heated to 450°C at a heating rate of 30°C / h, and then maintained for 10 h to reduce the catalyst. After reduction, the temperature was lowered to the reaction temperature for catalyst performance evaluation.

[0188] The catalyst compositions of the above examples and comparative examples are shown in Table 1.

[0189] Table 1

[0190]

[0191] Catalytic performance of the catalyst:

[0192] Catalyst evaluation conditions: fixed bed reactor, catalyst loading volume 50 mL, reaction temperature 160℃, reaction pressure 1.5 MPa, liquid space velocity of material 3h -1 The product composition after hydrogenation was analyzed by gas chromatography and bromine index instrument. The raffinate oil raw material used in catalyst evaluation contained 1.16wt% of benzene and had a bromine value of 15gBr / 100g. The activity and selectivity evaluation results of each catalyst are shown in Table 2.

[0193] Table 2

[0194]

[0195] As can be seen from Table 2, the catalyst provided by the present application has higher hydrogenation activity and selectivity and superior anti-coking performance.

[0196] Of course, the present application can have other various embodiments, and those skilled in the art can make various corresponding changes and modifications according to the present application without departing from the spirit and essence of the present application. However, these corresponding changes and modifications shall all belong to the protection scope of the present application.

Claims

1. A method for preparing an aromatic hydrocarbon raffinate hydrogenation catalyst, wherein the catalyst support is mainly alumina with a bimodal pore structure, wherein the pore size of the micropores in the bimodal pore structure is 5-20 nm and the pore size of the macropores is 30-250 nm, and the catalyst contains active components Pt, Ni, Cu, Ce, and Ru, wherein the main active component Pt is loaded in two steps, characterized in that... The preparation of the catalyst includes the following steps: (1) Dissolve Ni soluble precursor and Cu soluble precursor in water, add oil phase, surfactant and co-surfactant, stir to form microemulsion, add the high-temperature calcined support to the prepared microemulsion and impregnate for 0.5 to 4 hours, filter out the residual liquid, dry and calcinate to obtain semi-finished catalyst A; the particle size of the microemulsion is greater than 20 nm and less than 250 nm; (2) Dissolve the soluble precursor of Pt in water to obtain a solution containing Pt. The amount of solution is 100-115% of the saturated water absorption capacity of the semi-finished catalyst A. Adjust the pH to 1-3. Then add the semi-finished catalyst A to the solution containing Pt. After impregnation and adsorption for 0.5-4 hours, dry and calcine to obtain the semi-finished catalyst B. (3) Dissolve the soluble precursors of Ce and Pt together in deionized water to obtain a solution containing Ce and Pt. The solution volume is 100-115% of the saturated water absorption capacity of the semi-finished catalyst B. Adjust the pH to 1-5. Immerse the semi-finished catalyst B in the solution containing Ce and Pt. After the solution is completely absorbed, dry and calcine to obtain the semi-finished catalyst C. (4) Dissolve the precursor salt of Ru in deionized water to obtain a solution containing Ru. The amount of solution is 100-115% of the saturated water absorption rate of the semi-finished catalyst C. Immerse the semi-finished catalyst C in the solution containing Ru. After the solution is completely absorbed, dry and calcine to obtain the final catalyst. The surfactant is either an ionic or nonionic surfactant, the oil phase is C6-C8 saturated alkanes, the co-surfactant is C4-C6 alcohols, the weight ratio of the aqueous phase to the oil phase is 1-2.2, the weight ratio of the surfactant to the oil phase is 0.25-0.8, and the weight ratio of the surfactant to the co-surfactant is 1-1.

2.

2. The preparation method according to claim 1, characterized in that, Step (2) is performed before or after step (1).

3. The preparation method according to claim 1, characterized in that, The specific surface area of ​​the carrier is 140–230 m². 2 / g.

4. The preparation method according to claim 1, characterized in that, The surfactant is a nonionic surfactant; the oil phase is cyclohexane or n-hexane; and the co-surfactant is n-butanol or n-pentanol.

5. The preparation method according to claim 4, characterized in that, The surfactant is polyethylene glycol octylphenyl ether or hexadecyltrimethylammonium bromide.

6. The preparation method according to claim 2, characterized in that, The carrier contains more than 80 wt% alumina.

7. The preparation method according to claim 1, characterized in that, In step (3), the catalyst contains 0.1 to 0.6 wt% Ce and the Pt content co-impregnated with Ce is 0.005 to 0.05 wt%.

8. The preparation method according to claim 1 or 2, characterized in that, The soluble precursor of Pt is chloroplatinic acid; the soluble precursor of Ni is selected from at least one of nickel nitrate hexahydrate, nickel sulfate, and nickel chloride; the soluble precursor of Cu is selected from at least one of copper sulfate, copper chloride, and copper nitrate; the soluble precursor of Ce is selected from at least one of cerium chloride and cerium nitrate; and the soluble precursor of Ru is selected from at least one of ruthenium trichloride and ammonium ruthenate.

9. The preparation method according to claim 1 or 2, characterized in that, In step (1), step (2), step (3) or step (4), the roasting conditions are roasting at 400-600℃ for 3-6 hours.

10. An aromatic raffinate hydrogenation catalyst obtained by the preparation method according to any one of claims 1 to 9, comprising a support and an active component, characterized in that: The support is mainly alumina with a bimodal pore structure. The active components include Pt, Ni, Cu, Ce, and Ru. Based on the mass of the catalyst (100%), the Pt content is 0.1-0.55%, the Ni content is 1-6%, the Cu content is 0.1-1%, the Ce content is 0.1-0.6%, and the Ru content is 0.01-3%. The active components Ni and Cu are loaded in a microemulsion manner. The particle size of the microemulsion is larger than the maximum pore size of the support and smaller than the maximum macropore size of the support. The remaining active components are loaded in solution form. The active component Pt is loaded in two steps: in the first step, Pt is loaded alone, and in the second step, Ce and Pt are loaded simultaneously.

11. The catalyst according to claim 10, characterized in that, Based on the mass of the catalyst (100%), the Pt content is 0.2–0.4%, the Ni content is 2–4%, the Cu content is 0.3–0.8%, the Ce content is 0.2–0.45%, and the Ru content is 0.8–2%.

12. The catalyst according to claim 10, characterized in that, The reduction temperature of the catalyst is 350–450°C.

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