Catalytic gasoline hydrofining catalyst and method for preparing the same

Abstract

The application discloses a catalytic gasoline hydrofining catalyst and a preparation method thereof. The catalyst comprises a carrier of molybdenum, cobalt, phosphorus and a cobalt-manganese solid solution, and the amount of the phosphorus in the form of its oxide is 0.3-7 parts by weight based on 100 parts of the hydrofining catalyst. The carrier is a meso-macroporous alumina carrier, the total specific surface area of the carrier is 150-300 m 2 / g, and the total pore volume is 0.8-1.4 mL / g. The amount of the cobalt-manganese solid solution in the carrier is 0.5-15 parts by weight based on 100 parts of the carrier, and the balance is meso-macroporous alumina. The catalytic gasoline hydrofining catalyst is particularly suitable for selective hydrodesulfurization and denitrification of catalytic cracking (FCC) gasoline, and the hydrofining catalyst has the characteristics of high reaction activity and good selectivity.

Description

TECHNICAL FIELD

[0001] The present application relates to a hydrogenation catalyst, in particular to a catalytic gasoline hydrofining catalyst and a preparation method thereof. BACKGROUND

[0002] With the increasing requirements of environmental protection in the world, many domestic refineries use different methods to treat oil products for desulfurization, denitrification and other treatments, among which the hydrofining process is the most representative. Although the sulfur and nitrogen contents in the products after hydroprocessing can basically meet the requirements of the continuous upgrading standards of oil product quality, with the continuous deterioration of the quality of light oil products, the problems of excessive sulfur and nitrogen contents in light oil products and poor stability caused by them are increasingly prominent. Therefore, it is very urgent and necessary to deepen the systematic research on oil product desulfurization and denitrification processes and supporting catalysts, so as to further improve the quality of oil products to better meet the use requirements.

[0003] US 5441630 discloses a catalyst in which a Hydrotalcite-like (HTIC) is added as a support component to γ-Al2O3, and the calcined HTIC has a large surface area and is alkaline. The catalyst obtained by impregnating Co-Mo on the support shows high hydrodesulfurization (HDS) activity, but the octane loss of gasoline is also large.

[0004] US 5459118 discloses a new catalyst by introducing IA alkali metal based on the above catalyst components. The catalyst can make the degree of poisoning of the selective hydrogenation lattice on the surface of the catalyst much greater than that of the desulfurization lattice. The HDS activity of the catalyst is slightly lower than that of the selective hydrodesulfurization catalyst without adding such a poisoning agent, but the main problem of the catalyst is poor stability, especially the rapid decrease of the selectivity of the catalyst with the increase of the running time.

[0005] US 5525211A and US 5423976A use MgAl2O4 or activated carbon as a support, and add alkali metal, alkaline earth metal, lanthanide rare earth metal, IIIB metal or compounds thereof as an additive to the catalyst, which can effectively improve the selectivity of the catalyst for hydrodesulfurization. However, the stability of the catalyst is poor, and the selectivity decreases rapidly with the extension of the reaction time, which will greatly limit the industrial application of the catalyst.

[0006] US 5423976 and US 5538930 disclose the use of activated carbon as a support, which has a large surface area and is beneficial to the loading and dispersion of metal components. In addition, the activated carbon usually contains a certain amount of K, which can improve the selectivity of the catalyst. If the C support used does not contain the above-mentioned metals, the metals can be added at any step of the preparation of the catalyst. The disadvantage of the activated carbon support is that the loaded metal components and additives are easy to be lost.

[0007] WO 2005037959 discloses a method for improving the selectivity of a selective hydrodesulfurization catalyst for catalytically cracked gasoline. The specific steps are: first, adsorption denitrification of catalytically cracked gasoline to obtain an intermediate product; second, hydrodesulfurization treatment of the intermediate product. The denitrification adsorbent used is mainly exchange resin, alumina, silica, clay, organic or inorganic acid, polar solvent, etc.

[0008] US 4149965 discloses a method for improving the selectivity of a selective hydrodesulfurization catalyst for catalytically cracked gasoline. The method is mainly to adjust the reaction temperature and pressure, and to carry out a speed-up deactivation treatment on the fresh or regenerated catalyst, thereby improving the hydrogenation selectivity of the catalyst. The method disclosed in the patent can improve the selectivity of the catalyst, but the treatment process takes a long time, which is inconvenient for the start-up of the device, and in addition, the treatment process also reduces the desulfurization activity and service life of the catalyst.

[0009] CN 102151582A discloses a high-nitrogen poor-quality gasoline and diesel oil hydrodesulfurization catalyst, which uses Al2O3-TiO2-SiO2 ternary oxide as a composite carrier; the catalyst composition includes a carrier, an additive, and active metals. The active metals include oxides of nickel, molybdenum, and tungsten; the additive is phosphorus. The weight percentage content of each component based on the catalyst is: 1-15wt% of nickel oxide, 2-12wt% of molybdenum oxide; 12-35wt% of tungsten oxide, 2-5wt% of phosphorus pentoxide; 2-15wt% of titanium oxide; 2-20wt% of silicon oxide, and the rest is alumina. The preparation process first uses a room temperature complex method to configure a W-Mo-Ni-P co-impregnation solution with stable dissolution performance; then uses a step-by-step saturation impregnation technology to load the active metal components W-Mo-Ni and the additive P on the above carrier. The hydrodesulfurization and denitrogenation activity of the catalyst can be further improved.

[0010] CN 1040610A discloses a hydrofining catalyst with γ-Al2O3 containing TiO2 as a carrier, the content of titanium oxide in the carrier γ-Al2O3 is 5-30%, and W, Mo, Ni are used as active components. The performance of the hydrofining catalyst with TiO2 modified Al2O3 as a carrier can be further improved, but the carrier has a low acid amount, especially a small amount of strong acid centers, which is not conducive to the ring-opening and breaking of nitrogen heterocycles, and the denitrogenation effect is not obvious.

[0011] CN107583659A discloses a selective hydrodesulfurization catalyst, the composition of the catalyst is calculated by mass of oxide: active component CoO 3-5%, MoO3 10-13%, modifier of the carrier, the content of boron, phosphorus and potassium is respectively B2O3 2-3%, P2O5 1-2%, K2O 1-1.5%, composite oxide carrier 75.5-83%, the carrier of the catalyst is zinc aluminate-containing zinc oxide and alumina composite oxide prepared by non-constant pH alternating titration. The hydrodesulfurization catalyst provided by the patent has good desulfurization selectivity and stability, but the zinc aluminate contained in the carrier of the catalyst needs to be obtained by non-constant pH alternating titration, which brings certain difficulty to the industrialization of the catalyst.

[0012] CN 102626635B proposes a coal tar hydrodenitrogenation catalyst and its preparation and application, which takes Mo-W as the hydrogenation active component and mesoporous alumina as the carrier and is prepared by the equal-volume impregnation method. The catalyst is mainly suitable for coal tar with high nitrogen content, has a larger specific surface area and pore size, and therefore has high hydrodenitrogenation activity, and the hydrodenitrogenation rate is as high as 97% or more, but the desulfurization effect is general.

[0013] CN 102614909B discloses a catalyst for removing nitrogen-containing compounds in coal tar and its preparation and application, which has good mechanical strength, wear resistance and water resistance, takes tungsten trioxide, nickel monoxide and chromium sesquioxide as the active component, fluorine and phosphorus as the auxiliary agent, and alumina, zirconia, Hβ molecular sieve, binder and extrusion aid as the carrier, and can deeply remove nitrogen-containing and sulfur-containing compounds in low-temperature coal tar, but the catalyst has harsh reaction conditions.

[0014] Through extensive and in-depth research on oil hydrofining catalysts, it is shown that the methods proposed by the prior art can improve the selectivity of the hydrogenation catalyst, but at the same time, the activity and stability of the catalyst are also affected to some extent. Therefore, further in-depth research on oil hydrofining catalysts is carried out to improve the selectivity as much as possible while ensuring that the catalytic properties such as activity and stability are not affected, and it is hoped that it can show good application prospects in the field of petroleum chemical industry. SUMMARY

[0015] The purpose of the present application is to provide a catalytic gasoline hydrofining catalyst and its preparation method, especially for selective hydrodesulfurization and denitrification reactions of catalytic cracking (FCC) gasoline, which has the characteristics of high reaction activity and good selectivity.

[0016] To achieve the above object, the present application provides a catalytic gasoline hydrofining catalyst, which comprises molybdenum, cobalt, phosphorus, a carrier containing cobalt-manganese solid solution, and the amount of the phosphorus is 0.3-7 parts by weight of the hydrofining catalyst; the carrier is meso-macroporous alumina carrier, the total specific surface area of the carrier is 150-300 m 2 / g, the total pore volume is 0.8-1.4 mL / g; the amount of the cobalt-manganese solid solution in the carrier is 0.5-15 parts by weight of the carrier, and the meso-macroporous alumina is the remainder.

[0017] The catalytic gasoline hydrofining catalyst of the present application, the meso-macroporous alumina carrier has through pores and does not contain micropores from the perspective of mass transfer of materials. The pore size of the meso-macroporous alumina carrier is bimodal distribution, and each of the mesopore region and the macropore region has a concentrated distribution of pore size. The micropore referred to in the present application refers to a pore with a pore size of ≤2 nm.

[0018] The catalytic gasoline hydrofining catalyst of the present application, the carrier preferably has a total specific surface area of 170-240 m 2 / g, and a total pore volume of 0.9-1.2 mL / g.

[0019] As a preference, the mesopore pore volume accounts for 30-70% in the carrier of the present application, and the rest is macropore pore volume; the mesopore of the present application refers to a pore with a pore size of 2-50 nm, and the macropore refers to a pore with a pore size of ≥50 nm; further preferably, the average pore size of the mesopore is distributed in the range of 8-20 nm, and the average pore size of the macropore is distributed in the range of 80-150 nm. The mesopore pore volume ratio of the present application refers to the proportion of the mesopore pore volume in the total pore volume of the carrier. The pore volume and the average pore size are obtained by N2 physical adsorption-desorption.

[0020] The catalytic gasoline hydrofining catalyst of the present application, the cobalt-manganese solid solution is (Co x Mn y O4) n , wherein n is an integer of 1-10, 0

[0021] The catalytic gasoline hydrofining catalyst of the present application, the cobalt-manganese solid solution preferably contains cubic crystal system Co2MnO4, the crystal lattice type of Co2MnO4 belongs to cubic crystal system, and has characteristic diffraction peaks at 2θ=18.6°, 30.7°, 36.2°, 44.1°, 54.6°, 58.4°, 64.2° and 92.1°.

[0022] The catalytic gasoline hydrofining catalyst of the present application, the content of the cobalt-manganese solid solution should be controlled within the protection scope of the present application, and should not be too low, otherwise the effect cannot be achieved; nor should be too high, which will affect the overall pore distribution of the carrier, and will also increase the metal consumption of the hydrofining catalyst, and further increase the production cost of the catalyst, which is not economic and reasonable.

[0023] Preferably, the catalytic gasoline hydrofining catalyst of the present application, the content of the molybdenum calculated as its oxide is 2-18 parts, preferably 5-14 parts, based on 100 parts of the weight of the hydrofining catalyst.

[0024] Preferably, the catalytic gasoline hydrofining catalyst of the present application, the content of the cobalt calculated as its oxide is 0.5-7 parts, preferably 1-4 parts, based on 100 parts of the weight of the hydrofining catalyst.

[0025] Preferably, the catalytic gasoline hydrofining catalyst of the present application, the content of the phosphorus calculated as its oxide is 0.8-4.5 parts, based on 100 parts of the weight of the hydrofining catalyst.

[0026] Preferably, the catalytic gasoline hydrofining catalyst of the present application, the content of the cobalt-manganese solid solution is 1-10 parts, based on 100 parts of the weight of the carrier.

[0027] The catalytic gasoline hydrofining catalyst of the present application can also simultaneously optimize the content of molybdenum, cobalt, phosphorus and cobalt-manganese solid solution, i.e., the content of molybdenum calculated as its oxide is 5-14 parts, the content of cobalt calculated as its oxide is 1-4 parts, the content of phosphorus calculated as its oxide is 0.8-4.5 parts, and the content of cobalt-manganese solid solution is 1-10 parts.

[0028] The present application also provides a preparation method of the catalytic gasoline hydrofining catalyst, which specifically comprises the following steps:

[0029] The carrier is immersed in a solution containing phosphorus, molybdenum and cobalt, and then dried and calcined to obtain the hydrofining catalyst.

[0030] The preparation method of the catalytic gasoline hydrofining catalyst of the present application, the process conditions of the drying and calcining in the preparation process of the catalyst are for example but not limited to: drying at 100-150℃ for 2-8 hours, and calcining at 450-650℃ for 3-8 hours.

[0031] The preparation method of the catalytic gasoline hydrofining catalyst of the present application can have phosphorus, molybdenum and cobalt in any decomposable form such as oxide, halide or salt.

[0032] The preparation method of the catalytic gasoline hydrofining catalyst of the present application can have the impregnation method such as but not limited to at least one of isometric impregnation, spraying and excess impregnation.

[0033] The preparation method of the catalytic gasoline hydrofining catalyst of the present application can have the isometric impregnation method such as but not limited to specifically comprising the following steps: dissolving the precursor salts of phosphorus, molybdenum and cobalt in ammonia water in sequence according to the saturated water absorption rate of the carrier, preparing a system-stable mixed impregnation solution, isometric impregnation on the carrier, aging, drying, calcination, and preparing the catalytic gasoline hydrofining catalyst. The spraying method such as but not limited to specifically comprising the following steps: first, according to the catalyst formula, weighing an appropriate amount of precursor salts of phosphorus, molybdenum and cobalt, and testing the saturated water absorption rate of the alumina carrier used for the catalyst to determine the amount of water for dissolving the metal precursor salts; then, adding the metal precursor salts in sequence into deionized water, and adjusting the pH value by adding concentrated ammonia water, such as 25% by mass, to make the active metal precursor salts all dissolve into a system-stable mixed solution; using the spraying method to spray the precursor salt impregnation solution in a mist form on the carrier in a rotating drum environment, to obtain a catalyst precursor; finally, aging and high-temperature treatment are performed on the catalyst precursor, including drying treatment at 120-150℃ for 4-8 hours, and calcination treatment at 550-650℃ for 4-8 hours, to obtain the catalyst product.

[0034] The preparation method of the catalytic gasoline hydrofining catalyst of the present application can have the carrier prepared by one of the following methods:

[0035] Method (1): grinding alumina, cobalt-manganese solid solution and pore-expanding agent, dry mixing, adding a plasticizer and water, kneading, extruding into strips, drying and calcination to obtain the carrier.

[0036] Method (2): grinding alumina and pore-expanding agent, dry mixing, calcination to obtain meso-macroporous alumina powder; grinding and dry mixing meso-macroporous alumina powder, cobalt-manganese solid solution and extrusion aid, kneading with a plasticizer and water, extruding into strips, drying and calcination to obtain the carrier.

[0037] In the preparation of the carrier of the preparation method of the catalytic gasoline hydrofining catalyst of the present application, the alumina is selected from one or more of sodium metaaluminate, pseudoboehmite and aluminum sol, and pseudoboehmite is preferred. The present application does not particularly limit the source of alumina, which can be obtained by conventional preparation method or purchase.

[0038] The preparation method of the catalytic gasoline hydrofining catalyst of the present application, in the preparation of the carrier, the extrusion aid includes but is not limited to at least one of the following: pearl millet powder, starch, methyl cellulose, preferably pearl millet powder, and the addition amount is 3-12% of the carrier weight, preferably 5-10%.

[0039] The preparation method of the catalytic gasoline hydrofining catalyst of the present application, in the preparation of the carrier, the colloidal solvent is an acid, which can be an organic acid or an inorganic acid or a combination of the two, preferably at least one of the following: oxalic acid, citric acid, nitric acid, hydrochloric acid. The amount of the colloidal solvent is 1-10% of the carrier weight, preferably 2-6%.

[0040] The preparation method of the catalytic gasoline hydrofining catalyst of the present application, in the preparation process of the carrier, the process conditions of drying and calcination are as follows: drying at 80-120℃ for 3-10 hours, and calcination at 450-750℃ for 2-6 hours.

[0041] The preparation method of the catalytic gasoline hydrofining catalyst of the present application, the pore expander includes but is not limited to at least one of the following: carbon black, alkyl cellulose, starch, and bamboo powder, preferably green and low-cost bamboo powder. The amount of the pore expander is 1-20% of the weight of alumina, preferably 5-13%.

[0042] The preparation method of the catalytic gasoline hydrofining catalyst of the present application, the crystal phase composition of the cobalt-manganese solid solution is mainly controlled by the synthesis process, including the composition ratio, high-temperature heat treatment and other conditions.

[0043] For example, the preparation method of the cobalt-manganese solid solution can use: cobalt nitrate and manganese nitrate as raw materials to prepare a solution, and then add citric acid and mix uniformly. The mixed solution is placed in a water bath to evaporate water slowly, and a sol is gradually formed, and then converted into a gel. The gel is dried in air, and then heat treated at different temperatures to obtain cobalt-manganese solid solutions with different particle sizes.

[0044] The cobalt-manganese solid solution can also be prepared by: adding citric acid or a mixture of citric acid and acetylacetone organic ligand to the cobalt nitrate and manganese nitrate aqueous solution, adjusting the pH to 0-1.5, forming a gel at 50-70℃, and then drying and calcining to obtain a nano-sized cobalt-manganese solid solution.

[0045] Most preferably, the preparation method of the cobalt-manganese solid solution uses: adding ammonia water dropwise to the mixed solution of cobalt and manganese precursor salts, stirring while adding, adjusting the pH value of the solution to 8-11, and obtaining a precipitate; filtering, washing with water, and then drying at 80-150℃ for 2-10 hours and calcining at 500-1100℃ for 2-6 hours to obtain the cobalt-manganese solid solution.

[0046] In the preparation of the cobalt-manganese solid solution, the cobalt and manganese can be added in the form of at least one of nitrate, halide, etc., but the present application is not particularly limited thereto.

[0047] Compared with the prior art, the present application has at least the following beneficial effects:

[0048] The catalytic gasoline hydrofining catalyst of the present application, due to the cobalt-manganese solid solution contained in the carrier, solves the problem that when cobalt is introduced at one time during catalyst impregnation, the crystal grains grow and the dispersion becomes poor, thereby affecting the synergistic effect of the main active components during use. Meanwhile, the catalyst carrier has a meso-macro bimodal pore distribution, which reduces the diffusion resistance of macromolecular sulfur and nitrogen-containing compounds such as thiophene, alkylbenzothiophene, pyridine and other sulfur and nitrogen-containing substances in the catalyst pores, and accordingly improves the mass transfer efficiency of the reactants, so that the catalyst exhibits good hydrogenation activity and higher hydrogenation selectivity. The catalytic gasoline hydrofining catalyst of the present application can improve the desulfurization and denitrification activity, reduce the olefin hydrogenation saturation activity, and thereby reduce the RON loss. BRIEF DESCRIPTION OF DRAWINGS

[0049] Figure 1 XRD spectrum of the cobalt-manganese solid solution-containing carrier sample prepared in Example 1. It can be seen from the spectrum that the XRD spectrum of the sample contains the characteristic peaks of the cobalt-manganese solid solution and γ-Al2O3, which indicates that the sample is an alumina carrier containing a cobalt-manganese solid solution. DETAILED DESCRIPTION

[0050] The present application will be described in detail below by way of examples. It is necessary to point out here that the following examples are only used to further illustrate the present application and cannot be understood as limiting the scope of protection of the present application, and those skilled in the art can make some non-essential improvements and adjustments to the present application according to the above content of the present application.

[0051] In order to further illustrate the method adopted by the present application and the performance of the catalyst, examples are used to illustrate the hydrofining catalyst containing a cobalt-manganese solid solution prepared by the present application and the corresponding FCC gasoline hydrofining reaction, but the present application is not limited to the following examples.

[0052] Sources of raw materials for carrier and catalyst preparation:

[0053] The raw materials and reagents used in the present application are all commercially available products.

[0054] Detection method of total specific surface area, total pore volume, mesopore diameter and macropore diameter of the carrier:

[0055] N2 physical adsorption-desorption is used.

[0056] Sources of raw materials for hydrofining reaction:

[0057] The present application adopts Daqing petrochemical FCC full-range gasoline as raw material, the sulfur content is 295.4 mg / kg, the nitrogen content is 35.2 mg / kg, the olefin is 29.01 v%, and the RON is 92.7.

[0058] The product desulfurization rate, denitrogenation rate, olefin saturation rate and research octane number (RON) loss are calculated according to the following formula:

[0059]

[0060]

[0061]

[0062] Research octane number (RON) loss = research octane number of reaction raw material - research octane number of reaction product

[0063] Catalyst, reactant and product analysis method:

[0064] The sulfur content of the oil product is analyzed by TSN-2000 type sulfur and nitrogen tester. The oil product composition is analyzed by Agilent 7890B type gas chromatograph, and the data processing is completed by HW-2000PONA analysis special chromatographic workstation. The research octane number RON of the oil product is tested by octane number machine.

[0065] Example 1

[0066] Co2MnO4 preparation: Dissolve cobalt nitrate and manganese nitrate in deionized water to prepare a mixed solution containing cobalt and manganese, add ammonia water dropwise to the solution, add dropwise while stirring, adjust the pH value of the solution to 9.6, and obtain a precipitate. The precipitate is filtered, washed with water, dried at 135℃ for 4h, and calcined at 840℃ for 4h to obtain a cobalt-manganese solid solution Co2MnO4.

[0067] Preparation of the carrier: Co2MnO4, sodium aluminate and bamboo powder are ground and mixed to obtain a powder containing Co2MnO4. The powder containing Co2MnO4 and the sesbania powder are added to a mixer and mixed, and then an aqueous solution of nitric acid and citric acid is introduced into the mixer and kneaded to obtain a lump material, which is extruded into a strip, dried at 90℃ for 3h, and calcined at 750℃ for 3h to obtain a carrier A-1 containing Co2MnO4. The total specific surface area of the carrier A-1 is 183.3 m 2 / g, the total pore volume is 0.93 mL / g, the carrier A-1 has mesopores and macropores, the mesopore pore volume accounts for 61%, and the average mesopore diameter is 7.6 nm, and the average macropore diameter is 166.1 nm. The components and contents in the carrier A-1 are shown in Table 1.

[0068] Ammonium heptamolybdate, cobalt acetate and phosphoric acid were dissolved in an aqueous ammonia solution to prepare an impregnation solution of active components completely dissolved. The impregnation solution of active components was sprayed in a mist form on the carrier A-1 in a rotating drum at room temperature to obtain a catalyst precursor, which was aged at room temperature for 4 h, dried at 130 °C for 7.5 h and calcined at 600 °C for 3 h to prepare a hydrofining catalyst C-1. The components and contents in the hydrofining catalyst C-1 are shown in Table 2.

[0069] Example 2

[0070] Co2MnO4 / CoMnO3 preparation: Cobalt nitrate and manganese nitrate were dissolved in deionized water to prepare a mixed solution containing cobalt and manganese. Ammonia water was added dropwise to the solution while stirring, and the pH value of the solution was adjusted to 10.4. The process resulted in a precipitate, which was filtered, washed with water, dried at 120 °C for 7 h and calcined at 780 °C for 6 h to obtain a cobalt-manganese solid solution Co2MnO4 / CoMnO3.

[0071] Carrier preparation: Pseudo-boehmite and bamboo powder were ground and dry-mixed, and then calcined at 650 °C for 8 h to obtain a mesoporous and macroporous alumina powder. The powder was ground and dry-mixed with the Co2MnO4 / CoMnO3 solid solution powder and the sesbania powder. An aqueous nitric acid solution was then introduced into the mixture and kneaded to obtain a lumped material, which was extruded into a strip, dried at 120 °C for 5 h and calcined at 700 °C for 5 h to finally obtain a carrier A-2 containing Co2MnO4 / CoMnO3. The total specific surface area of the carrier A-2 was 295.6 m2 / g, and the total pore volume was 1.22 mL / g. The carrier A-2 had mesopores and macropores, and the mesopore volume accounted for 35%. The average mesopore diameter was 10.1 nm, and the average macropore diameter was 89.8 nm. The components and contents in the carrier A-2 are shown in Table 1. 2

[0072] Ammonium heptamolybdate, cobalt acetate and ammonium dihydrogen phosphate were dissolved in an aqueous ammonia solution to prepare an impregnation solution of active components completely dissolved. The impregnation solution of active components was impregnated in an equal volume of the carrier A-2 at room temperature to obtain a catalyst precursor, which was aged at room temperature for 7 h, dried at 115 °C for 4.5 h and calcined at 540 °C for 6 h to prepare a hydrofining catalyst C-2. The components and contents in the hydrofining catalyst C-2 are shown in Table 2.

[0073] Example 3

[0074] Co2Mn3O8 preparation: Cobalt acetate and manganese dichloride were dissolved in deionized water to prepare a mixed solution containing cobalt and manganese. Ammonia water was added dropwise to the solution while stirring, and the pH value of the solution was adjusted to 8.1. The process resulted in a precipitate, which was filtered, washed with water, dried at 95 °C for 9 h and calcined at 1100 °C for 3 h to obtain a cobalt-manganese solid solution Co2Mn3O8.​

[0075] Preparation of the carrier: Co2Mn3O8, sodium aluminate and carbon black were dry-mixed to obtain a Co2Mn3O8-containing powder. The Co2Mn3O8-containing powder and methyl cellulose were mixed in a mixer, and then an aqueous oxalic acid solution was introduced into the mixture to knead, to obtain a lumped material, which was extruded into a strip, dried at 110°C for 6h, and calcined at 650°C for 4h, to finally obtain the Co2Mn3O8-containing carrier A-3. It was detected that the total specific surface area of the carrier A-3 was 174.1m2 / g, the total pore volume was 1.35mL / g, the carrier A-3 had mesopores and macropores, the mesopore pore volume accounted for 42%, the average mesopore diameter was 15.4nm, and the average macropore diameter was 101.7nm. The components and contents in the carrier A-3 are shown in Table 1. 2

[0076] An ammonium heptamolybdate, cobalt chloride and phosphoric acid solution was dissolved in an aqueous ammonia solution to prepare an active component impregnation solution completely dissolved. The active component impregnation solution was excess-impregnated in the carrier A-3 at room temperature to obtain a catalyst precursor, which was aged at room temperature for 7h, dried at 150°C for 2h, and calcined at 480°C for 8h, to prepare a hydrofining catalyst C-3. The components and contents in the hydrofining catalyst C-3 are shown in Table 2.

[0077] Example 4

[0078] Preparation of CoMnO3: Cobalt chloride and manganese acetate were dissolved in deionized water to prepare a mixed solution containing cobalt and manganese, and then ammonia water was added dropwise to the solution while stirring, and the pH value of the solution was adjusted to 8.8. A precipitate was obtained in the process, which was filtered, washed with water, dried at 110°C for 3h, and calcined at 730°C for 5h, to obtain a cobalt-manganese solid solution CoMnO3.

[0079] Preparation of the carrier: Pseudo-boehmite and starch were ground and then dry-mixed, and then the mixture was calcined at 570°C for 4h to obtain a meso-macroporous alumina powder. The above powder, CoMnO3 solid solution powder and methyl cellulose were respectively ground and dry-mixed, and then an aqueous nitric acid solution was introduced into the mixture to knead, to obtain a lumped material, which was extruded into a strip, dried at 100°C for 4h, and calcined at 570°C for 6h, to finally obtain a CoMnO3-containing carrier A-4. It was detected that the total specific surface area of the carrier A-4 was 232.8m2 / g, the total pore volume was 0.84mL / g, the carrier A-4 had mesopores and macropores, the mesopore pore volume accounted for 68%, the average mesopore diameter was 19.2nm, and the average macropore diameter was 123.5nm. The components and contents in the carrier A-4 are shown in Table 1. 2

[0080] ​​Ammonium heptamolybdate, cobalt nitrate, ammonium dihydrogen phosphate were dissolved in aqueous ammonia solution to prepare an impregnation solution of active components completely dissolved. The impregnation solution was impregnated into carrier A-4 at room temperature to obtain a catalyst precursor, which was aged at room temperature for 5 h, dried at 120 °C for 6 h, and calcined at 570 °C for 4 h to prepare a hydrofining catalyst C-4. The components and contents in the hydrofining catalyst C-4 are shown in Table 2.

[0081] Example 5

[0082] Preparation of CoMn2O4: Cobalt nitrate and manganese acetate were dissolved in deionized water to prepare a mixed solution containing cobalt and manganese. Ammonia water was added dropwise to the solution while stirring, and the pH value of the solution was adjusted to 10.9. The precipitate was obtained, filtered, washed with water, dried at 150 °C for 6 h, and calcined at 960 °C for 4 h to obtain a cobalt-manganese solid solution CoMn2O4.

[0083] Preparation of the carrier: Pseudo-boehmite and carbon black were ground and dry-mixed, and then calcined at 700 °C for 3 h to obtain a mesoporous-alumina powder. The powder was ground and dry-mixed with CoMn2O4 solid solution powder and sesbania powder. After mixing, an aqueous solution of nitric acid and oxalic acid was introduced into the mixture to obtain a kneaded material, which was extruded into a strip, dried at 80 °C for 8 h, and calcined at 490 °C for 5 h to obtain a carrier A-5 containing CoMn2O4. The total specific surface area of the carrier A-5 was 153.2 m 2 / g, and the total pore volume was 1.08 mL / g. The carrier A-5 had mesopores and macropores, and the mesopore volume accounted for 53%, with an average mesopore diameter of 5.3 nm and an average macropore diameter of 148.6 nm. The components and contents in the carrier A-5 are shown in Table 1.

[0084] Ammonium heptamolybdate, cobalt nitrate, and phosphoric acid were dissolved in aqueous ammonia solution to prepare an impregnation solution of active components completely dissolved. The impregnation solution was sprayed in a mist form on the carrier A-5 in a rotating drum environment to obtain a catalyst precursor, which was aged at room temperature for 3 h, dried at 105 °C for 3 h, and calcined at 640 °C for 3 h to prepare a hydrofining catalyst C-5. The components and contents in the hydrofining catalyst C-5 are shown in Table 2.

[0085] Comparative Example 1

[0086] The difference from Example 1 is that Co2MnO4 is not prepared, and Co2MnO4 is not added in the preparation of the carrier. The total specific surface area of the obtained carrier B-1 was 190.2 m 2 / g, the total pore volume was 0.95 mL / g, the support B-1 had mesopores and macropores, the mesopore volume accounted for 66%, the average mesopore diameter was 7.4 nm, and the average macropore diameter was 166.9 nm. The components and contents in the obtained support B-1 are shown in Table 1, and the components and contents in the hydrofining catalyst C-D1 are shown in Table 2.

[0087] Comparative Example 2

[0088] The difference from Example 1 is that Co2MnO4 and the support are not prepared, and a commercially available alumina support B-2 is used in the preparation of the catalyst. It is detected that the total specific surface area of the support B-2 is 327.6 m 2 / g, the total pore volume was 0.69 mL / g, the support B-2 had mesopores, the mesopore volume accounted for 92%, and the average mesopore diameter was 10.7 nm. The components and contents in the obtained alumina support B-2 are shown in Table 1, and the components and contents in the hydrofining catalyst C-D2 are shown in Table 2.

[0089] Table 1 Composition and content of the support

[0090]

[0091] Table 2 Composition and content of the hydrofining catalyst

[0092]

[0093]

[0094] Hydrofining performance reaction evaluation

[0095] The catalysts obtained in the examples and comparative examples are used for hydrofining reaction performance evaluation, and the hydrofining reaction process conditions are as follows:

[0096] The hydrofining catalyst is loaded in a 30 mL fixed bed isothermal reactor for reaction performance evaluation. Before the evaluation, the hydrofining catalyst needs to be pre-sulfurized using sulfurized oil. The treatment is carried out in a hydrogen atmosphere, using straight-run gasoline as the sulfurized oil and CS2 as the sulfurizing agent, under the conditions of a pressure of 3.0 MPa, a volume space velocity of 3.0 h -1 , and a hydrogen / oil volume ratio of 350:1. During the sulfurization, the temperature of the catalyst bed is increased at a rate of 20 ℃ / h, and is kept constant at two temperature sections of 230 ℃ and 280 ℃, with a constant temperature time of 5 h. After the pre-sulfurization process is completed, the reaction operation process conditions are adjusted to the operating conditions, and the sulfurized oil is switched to FCC full-range gasoline, entering the reaction stage. The reaction operation process conditions are an inlet temperature of 260 ℃, a pressure of 2.2 MPa, a volume space velocity of 1.5 h -1 , and a hydrogen / oil volume ratio of 450:1.

[0097] The results of the evaluation of the hydrofining reaction performance of the catalysts obtained in the examples and comparative examples are shown in Table 3.

[0098] Table 3 Evaluation results of the hydrofining reaction performance of the catalysts of examples and comparative examples

[0099] Catalyst name Desulfurization rate, % Denitrogenation rate, % Olefin saturation rate, % RON loss C-1 92.04 27.35 15.99 1.5 C-2 95.41 31.92 17.67 1.4 C-3 94.86 28.15 17.98 1.4 C-4 92.55 27.47 16.54 1.6 C-5 91.70 25.88 17.52 1.5 C-D1 90.53 22.13 15.26 1.6 C-D2 91.01 21.52 17.48 1.6

[0100] From the results of the examples and comparative examples, it can be seen that the catalytic gasoline hydrofining catalyst of the present application exhibits better hydrogenation activity and higher hydrogenation selectivity, and can improve the desulfurization and denitrification activity, reduce the olefin hydrogenation saturation activity, and thus reduce the RON loss.

[0101] Of course, the present application can have other various embodiments and modifications, 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, but these corresponding changes and modifications should all belong to the protection scope of the claims of the present application.

Claims

1. A catalytic gasoline hydrofining catalyst characterized in that, The catalyst comprises molybdenum, cobalt, phosphorus, a carrier containing cobalt-manganese solid solution, the amount of the phosphorus in the form of its oxide is 0.3-7 parts by weight based on 100 parts of the hydrofining catalyst; the carrier is meso-macroporous alumina carrier, the total specific surface area of the carrier is 150-300 m 2 / g, the total pore volume is 0.8-1.4 mL / g; the amount of the cobalt-manganese solid solution in the carrier is 0.5-15 parts by weight based on 100 parts of the carrier, and the rest is meso-macroporous alumina.

2. The hydrofinishing catalyst of claim 1, wherein, The total specific surface area of the carrier is 170-240 m 2 / g, and the total pore volume is 0.9-1.2 mL / g.

3. The hydrofinishing catalyst of claim 1, wherein, The pore of the carrier is a through hole, has mesopores and macropores, the mesopore volume ratio is 30-70%, the mesopore size distribution is 8-20 nm, and the macropore size distribution is 60-100 nm.

4. The hydrofinishing catalyst of claim 1, wherein, The cobalt-manganese solid solution is (Co x Mn y O4) n wherein n is an integer of 1 to 10, 0 < x < 5, and 0 < y < 5.

5. The hydrofinishing catalyst of claim 4, wherein, n is an integer of 1-5, 0.5 6. The hydrofinishing catalyst of claim 1, wherein, The cobalt-manganese solid solution includes at least one of CoMn2O4, Co2MnO4, CoMnO3 and Co2Mn3O8.

7. The hydrofmishing catalyst according to any one of claims 4 to 6, characterized in that, The cobalt-manganese solid solution contains Co2MnO4 in a cubic crystal system.

8. The hydrofinishing catalyst of claim 1, wherein, The amount of the molybdenum, as its oxide, is 2-18 parts based on 100 parts of the weight of the hydrofining catalyst.

9. The hydrofinishing catalyst of claim 1, wherein, The amount of the molybdenum, as its oxide, is 5-14 parts based on 100 parts of the weight of the hydrofining catalyst.

10. The hydrofinishing catalyst of claim 1, wherein, The amount of the cobalt, as its oxide, is 0.5-9 parts based on 100 parts of the weight of the hydrofining catalyst.

11. The hydrofinishing catalyst of claim 1, wherein, The amount of the cobalt, as its oxide, is 1-4 parts based on 100 parts of the weight of the hydrofining catalyst.

12. The hydrofmishing catalyst of claim 1, wherein, The amount of the phosphorus, as its oxide, is 0.8-4.5 parts based on 100 parts of the weight of the hydrofining catalyst.

13. The hydrofinishing catalyst of claim 1, wherein, The amount of the cobalt-manganese solid solution is 1-10 parts based on 100 parts of the weight of the carrier.

14. A process for preparing the catalytic gasoline hydrofining catalyst according to any one of claims 1 to 13, characterized in that, The method includes the following steps: The carrier is immersed in a solution containing phosphorus, molybdenum and cobalt, and then dried and calcined to obtain the hydrofining catalyst.

15. The preparation method according to claim 14, characterized in that, The preparation process of the carrier specifically includes the following steps: The alumina, the cobalt-manganese solid solution and the pore-expanding agent are ground, dry-mixed, and then the extrusion aid is added for further dry-mixing; after the powder mixture is uniformly mixed, the peptizing agent and water are added for kneading; and then the extruded strip is formed, dried and calcined to obtain the carrier.

16. The method of claim 14, wherein, The preparation process of the carrier specifically includes the following steps: The alumina and the pore-expanding agent are ground and dry-mixed, and then calcined to obtain the meso-macroporous alumina powder; the meso-macroporous alumina powder, the cobalt-manganese solid solution and the extrusion aid are ground and dry-mixed respectively, and then kneaded with the peptizing agent and water; and then the extruded strip is formed, dried and calcined to obtain the carrier.

17. The method of manufacturing according to claim 15 or 16, characterized in that, The extrusion aid is at least one of pearl millet powder, starch and methyl cellulose.

18. The production method according to claim 15 or 16, characterized by, The peptizing agent is at least one of an organic acid and an inorganic acid.

19. The production method according to claim 15 or 16, characterized by, The peptizing agent is at least one of oxalic acid, citric acid, nitric acid and hydrochloric acid.

20. The method of manufacturing according to claim 15 or 16, wherein, The pore-expanding agent is at least one of carbon black, alkyl cellulose, starch and bamboo powder.

21. The method of manufacturing according to claim 15 or 16, wherein, The pore-expanding agent is bamboo powder.

22. The method of claim 14, wherein, The impregnation method is at least one of the equal-volume impregnation carrier method, the spraying method and the excess impregnation method.

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