Hydroisomerization catalyst, method for preparing same, and use thereof

Abstract

The application relates to the field of catalysis technology, and particularly discloses a hydroisomerization catalyst, a preparation method and application thereof. The hydroisomerization catalyst comprises the following components in parts by weight: 97.5-99.4 parts of a molecular sieve carrier, 0.5-1.5 parts of an oxide containing an active metal, and 0.1-1.0 parts of an oxide containing an auxiliary metal. The molecular sieve carrier is synthesized by using double templates. In the oxide containing the active metal, the active metal is selected from one or a combination of platinum-palladium combination, molybdenum-tungsten combination and nickel-cobalt combination. In the oxide containing the auxiliary metal, the auxiliary metal is cerium. The preparation method comprises the following steps: co-impregnating a salt solution containing the active metal and the auxiliary metal on the molecular sieve carrier, drying, and reducing by hydrogen to obtain the hydroisomerization catalyst. When the hydroisomerization catalyst is applied, the conversion rate, selectivity and water-oxygen resistance are synergistically considered and improved, and the overall application effect and service life are significantly enhanced.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of catalysis technology, more particularly, it relates to a hydroisomerization catalyst, a preparation method and application thereof. BACKGROUND

[0002] The hydroisomerization catalyst refers to a catalyst capable of catalyzing the hydroisomerization reaction of petroleum hydrocarbon molecules. Under high temperature and high pressure, the catalyst acts on the carbon-carbon double bond and carbon-carbon triple bond in the petroleum hydrocarbon raw material together with a hydrogenation agent (such as hydrogen) to break and recombine, forming relatively symmetrical and shorter chain isomerized hydrocarbons, thereby improving the octane rating of the fuel. At the same time, the hydroisomerization catalyst can also degrade toxic and harmful substances such as benzene, alcohol and ether in the reaction, reducing harmful substance emissions in vehicle exhaust.

[0003] The hydroisomerization catalyst is usually composed of a metal active component (such as platinum group metal) and an acidic carrier (such as molecular sieve), which realizes the conversion of straight-chain alkanes to branched-chain alkanes through synergistic effect. In the application process, the metal active site adsorbs hydrogen molecules and dissociates into hydrogen atoms to participate in the hydrogenation reaction, while the acidic carrier (such as molecular sieve) provides acid catalytic sites to promote carbon chain breaking and branch generation, and optimize the performance of the oil product.

[0004] At present, biodiesel is a long-chain fatty acid monoalkyl ester renewable fuel prepared by transesterification reaction with plant oil, animal fat or waste oil as raw material; biojet fuel is a clean aviation fuel prepared by hydrogenation deoxidization, isomerization and other processes with renewable resources such as catering waste oil and animal and plant oil; both have excellent environmental performance, fuel performance close to petrochemical diesel, and wide raw material sources and renewable, so they are widely used, and the hydroisomerization catalyst is also applied to biodiesel and biojet fuel.

[0005] The existing hydroisomerization catalysts generally have the problem of insufficient selectivity of active sites, which leads to a high amount of by-products, affects the hydrogen partial pressure stability and catalyst activity, and the water and oxygen tolerance is also not good, which easily causes the activity retention rate to decrease when the raw material contains water, so it is difficult to realize the conversion rate, selectivity and water and oxygen tolerance of biodiesel and biojet fuel, and at present, a scheme is urgently needed to solve the above technical problems. SUMMARY

[0006] In order to realize the conversion rate, selectivity and water and oxygen tolerance of the hydroisomerization catalyst, the present application provides a hydroisomerization catalyst.

[0007] In a first aspect, the present application provides a hydroisomerization catalyst, which adopts the following technical scheme:

[0008] A hydroisomerization catalyst, comprising the following components by weight:

[0009] Molecular sieve carrier 97.5-99.4 parts;

[0010] Active metal-containing oxide 0.5-1.5 parts;

[0011] Auxiliary metal-containing oxide 0.1-1.0 parts;

[0012] The molecular sieve carrier is synthesized by using a double template agent;

[0013] In the active metal-containing oxide, the active metal is selected from one or a combination of platinum-palladium combination, molybdenum-tungsten combination, and nickel-cobalt combination;

[0014] In the auxiliary metal-containing oxide, the auxiliary metal is cerium.

[0015] By using the above technical solution, the synthesis of the molecular sieve carrier by using a double template agent can accurately control the pore topological structure of the molecular sieve, forming a hierarchical meso-micropore system, in which the mesopore accelerates the diffusion of long-chain alkanes, the micropore provides isomerization active sites, and can promote the catalytic effect of the pore mouth and inhibit the cracking side reaction. In the active metal-containing oxide, the active metal is selected from platinum-palladium combination, which can enhance the dehydrogenation / hydrogenation ability and has high electron transfer efficiency; the active metal is selected from molybdenum-tungsten combination, which can form a sulfide active phase and has strong anti-carbon deposition ability; the active metal is selected from nickel-cobalt combination, which is a non-noble metal low-cost solution but can synergize with the acid center of the molecular sieve. In the auxiliary metal-containing oxide, the auxiliary metal is cerium, which can capture active metal electrons by using the oxygen vacancies of its oxide, improve the intrinsic hydrogenation activity of the metal site, buffer oxygen impact, and reduce acid center hydrolysis, and maintain the stability of the catalyst. In this way, the hydrogen isomerization catalyst containing the above components achieves a synergistic improvement in conversion rate, selectivity, and water-oxygen resistance when applied, and significantly enhances the overall application effect and service life.

[0016] Preferably, the active metal is composed of the following components by weight:

[0017] Platinum-palladium combination 0.4-0.8 parts;

[0018] Molybdenum-tungsten combination 0.3-0.6 parts;

[0019] Nickel-cobalt combination 0.1-0.4 parts.

[0020] By adopting the technical scheme, the platinum-palladium combination, the molybdenum-tungsten combination and the nickel-cobalt combination are used as active metals in the above weight proportions, in the process, platinum and palladium form an electron-rich structure to promote hydrogen molecular dissociation and adsorption; molybdenum and tungsten provide strong hydrogenation active sites and are bonded with the molecular sieve framework oxygen to bring about framework anchoring; nickel and cobalt reduce the isomerization activation energy, accelerate the hydrogenation stability of carbonium ions and reduce cracking by-products; through the ternary synergy of the platinum-palladium combination, the molybdenum-tungsten combination and the nickel-cobalt combination, a complex action system of "platinum-palladium activation-molybdenum-tungsten sulfur resistance-nickel-cobalt diffusion optimization" is formed, which brings about comprehensive improvement of conversion rate, selectivity and water-oxygen resistance, and a hydrogenation isomerization catalyst with better quality can be obtained.

[0021] Preferably, the platinum-palladium combination is composed of platinum and palladium in a weight ratio of (0.9-1.1):1;

[0022] The molybdenum-tungsten combination is composed of molybdenum and tungsten in a weight ratio of (2.8-3.2):1;

[0023] The nickel-cobalt combination is composed of nickel and cobalt in a weight ratio of (1.8-2.2):1.

[0024] By adopting the technical scheme, the platinum-palladium combination mainly drives rapid dehydrogenation, the molybdenum-tungsten combination mainly guarantees sulfur resistance stability, and the nickel-cobalt combination mainly inhibits cracking side reactions. In addition to the above excellent effects, the platinum-palladium combination, the molybdenum-tungsten combination and the nickel-cobalt combination composed of the above proportion of raw materials can also achieve conversion rate-selectivity balance, inhibit oxygen adsorption, capture free oxygen and reduce active site oxidation, thereby exhibiting a better water-oxygen resistance mechanism, so that the hydrogenation isomerization catalyst performs better in conversion rate, selectivity and water-oxygen resistance.

[0025] Preferably, the molecular sieve carrier is prepared by the following steps:

[0026] The silicon source, the aluminum source and the double template agent are dissolved in water, the pH is adjusted to 10-11, and then hydrothermal crystallization treatment is performed, followed by washing, drying and calcination to obtain the molecular sieve carrier.

[0027] By adopting the technical scheme, in the above preparation process, the double template agent produces mesopores or micropores in the crystallization process to construct pore structures and provide isomerization active sites; and adjusting the pH to 10-11 can promote the polycondensation of silicate and aluminate and stabilize the silicate-aluminate colloid, so that the double template agent is bonded with the framework in the subsequent hydrothermal crystallization process to form a network of through mesopores or micropores, realize precise design of the carrier pore structure and acid sites, and then obtain a molecular sieve carrier with better quality.

[0028] Preferably, the temperature of the hydrothermal crystallization treatment is 160-180℃, and the time is 68-76h; the calcination temperature is 540-560℃, and the calcination time is 5-6h.

[0029] By adopting the technical scheme, the condensation rate of silicate-aluminate is significantly slowed down at 160-180℃, and the generation of miscellaneous phases such as sodalite is avoided, the time is 68-76h, so that the double template agent fully penetrates the gel network and forms intercrystalline pores with concentrated pore size distribution; finally, the calcination temperature is 540-560℃, and the calcination time is 5-6h, which can realize the complete carbonization and removal of the double template agent, and avoid the collapse of the pore channel, and then obtain a stable molecular sieve carrier with excellent quality.

[0030] Preferably, the double template agent is composed of C6H 14 Br2 and TEAOH in a molar ratio of 1: (2-4).

[0031] By adopting the technical scheme, the above ratio can make TEAOH fully neutralize C6H 14 Br2 hydrolysis produces H + , maintains the alkaline environment of pH=10-11, guarantees the condensation rate of silicate-aluminate and the purity of the crystal, and can inhibit the excessive expansion of the pore channel, maintain the mechanical strength of the framework, and make the pore channel best, and then precisely control the pore structure and acid site distribution of the molecular sieve carrier through synergistic effect, and obtain a molecular sieve carrier with better quality.

[0032] Preferably, after the hydrothermal crystallization treatment is completed, it is converted into H type through NH4Cl ion exchange; wherein, the concentration of the used NH4Cl solution is 0.4-0.6 mol / L, the temperature is 55-65℃, and the time is 1.8-2.2h.

[0033] By adopting the technical scheme, NH4 + By ion exchange, Na + in the molecular sieve framework is replaced by NH4 + , which is decomposed into H 2 after calcination, forming B acid sites and directly improving the catalytic activity, and can inhibit the dealumination of the framework; and the selection of the concentration of the above NH4Cl solution and the temperature and time can realize the synergistic optimization of kinetics and stability, guarantee the exchange depth and acid stability control, and is beneficial to precisely control the proton replacement efficiency and the framework stability, realize the efficient construction of the molecular sieve acid site and the protection of the structural integrity.

[0034] Preferably, the molecular sieve carrier has three-dimensional ten-membered ring cross-pore channels, which are 0.54x0.56 nm straight channels and 0.52x0.58 nm Z-shaped channels, the specific surface area is 150-230 m 2 / g, and the total acid amount is 0.9-2.8 mmol / g.

[0035] By adopting the technical scheme, the straight channel reduces the diffusion resistance of linear molecules, improves the mass transfer efficiency of reactants, the Z-shaped channel screens isomer molecules through the curved hole, enhances the product selectivity, and the hole intersection forms a locally enlarged cavity, concentrates strong acid sites, and becomes a key catalytic active center; meanwhile, by controlling the specific surface area and total acid amount, the acid site exposure density can be increased, the acid strength and distribution are optimized, and then the excellent catalytic performance is ensured.

[0036] In a second aspect, the application provides a preparation method of a hydroisomerization catalyst, which adopts the following technical scheme:

[0037] A preparation method of a hydroisomerization catalyst, comprising the following steps:

[0038] (1) preparing raw materials including a molecular sieve carrier, a salt solution containing active metals and auxiliary metal according to the preparation requirements;

[0039] (2) co-impregnating the salt solution containing active metals and auxiliary metals in the molecular sieve carrier, drying, and then reducing by hydrogen to obtain a hydroisomerization catalyst.

[0040] In a third aspect, the application provides an application of a hydroisomerization catalyst in producing biodiesel and biojet fuel.

[0041] In summary, the application has the following beneficial effects:

[0042] The molecular sieve carrier prepared by the application, the combination of platinum and palladium, the combination of molybdenum and tungsten, and the combination of nickel and cobalt as active metals, and the auxiliary metal can make the obtained hydroisomerization catalyst realize the synergistic consideration and improvement of conversion rate, selectivity and water-oxygen resistance, and significantly enhance the overall application effect and service life. DETAILED DESCRIPTION

[0043] The application will be further described in detail below in combination with preparation examples, examples and comparative examples.

[0044] The raw materials used in each preparation example, example and comparative example of the application are commercially available, except for special instructions.

[0045] The silicon source is silica sol, and the SiO2 content is 40 wt%;

[0046] The aluminum source is sodium aluminate;

[0047] The salt solution containing platinum metal is H2PtCl6 solution;

[0048] The salt solution containing palladium metal is Pd(NO3)2 solution;

[0049] The salt solution containing molybdenum metal is (NH4)2MoO4 solution;

[0050] The salt solution containing tungsten metal is an ammonium metatungstate solution;

[0051] The salt solution containing nickel metal is a Ni(NO3)2 solution;

[0052] The salt solution containing cobalt metal is a Co(NO3)2 solution;

[0053] The salt solution containing cerium metal is a Ce(NO3)3 solution.

[0054] Preparation examples of raw materials and / or intermediates

[0055] Preparation example 1

[0056] A molecular sieve carrier is prepared by the following steps:

[0057] The silicon source, the aluminum source and the double template are dissolved in water, and the pH is adjusted to 10-11 with ammonia water, and then hydrothermal crystallization treatment is performed, and then the molecular sieve carrier is obtained after washing, drying and calcination.

[0058] Note: The molar ratio of SiO2 and Al2O3 in the molecular sieve carrier is 40. The amount of the double template is 12% of the total weight of the silicon source and the aluminum source. The hydrothermal crystallization treatment temperature is 170°C, and the time is 72h; the calcination temperature is 550°C, and the calcination time is 5.5h. The double template is composed of C6H 14 Br2 and TEAOH in a molar ratio of 1:3. The molecular sieve carrier has three-dimensional ten-membered ring intersecting channels, which are 0.54×0.56 nm straight channels and 0.52×0.58 nm Z-shaped channels, and the specific surface area is 190m 2 / g, and the total acid amount is 1.85mmol / g.

[0059] Preparation example 2

[0060] A molecular sieve carrier, which is different from preparation example 1 in that the hydrothermal crystallization treatment temperature is 160°C, and the time is 76h; the calcination temperature is 540°C, and the calcination time is 6h.

[0061] Preparation example 3

[0062] A molecular sieve carrier, which is different from preparation example 1 in that the hydrothermal crystallization treatment temperature is 180°C, and the time is 68h; the calcination temperature is 560°C, and the calcination time is 5h.

[0063] Preparation example 4

[0064] A molecular sieve carrier, which is different from preparation example 1 in that the double template is composed of C6H 14 Br2 and TEAOH in a molar ratio of 1:2.

[0065] Preparation Example 5

[0066] A molecular sieve carrier, different from Preparation Example 1, is that the double template is composed of C6H 14 Br2 and TEAOH are composed in a molar ratio of 1:4.

[0067] Preparation Example 6

[0068] A molecular sieve carrier, different from Preparation Example 1, is that the molecular sieve carrier has three-dimensional ten-membered ring crossed channels, which are 0.54×0.56 nm straight channels and 0.52×0.58 nm Z-shaped channels, and the specific surface area is 150 m 2 / g, and the total acid amount is 0.9 mmol / g.

[0069] Preparation Example 7

[0070] A molecular sieve carrier, different from Preparation Example 1, is that the molecular sieve carrier has three-dimensional ten-membered ring crossed channels, which are 0.54×0.56 nm straight channels and 0.52×0.58 nm Z-shaped channels, and the specific surface area is 230 m 2 / g, and the total acid amount is 2.8 mmol / g.

[0071] Preparation Example 8

[0072] A molecular sieve carrier, different from Preparation Example 1, is that after the hydrothermal crystallization treatment is completed, it is converted into H type through NH4Cl ion exchange; wherein the concentration of the NH4Cl solution used is 0.5 mol / L, the temperature is 60℃, and the time is 2h.

[0073] Preparation Example 9

[0074] A molecular sieve carrier, different from Preparation Example 1, is that after the hydrothermal crystallization treatment is completed, it is converted into H type through NH4Cl ion exchange; wherein the concentration of the NH4Cl solution used is 0.4 mol / L, the temperature is 55℃, and the time is 2.2h.

[0075] Preparation Example 10

[0076] A molecular sieve carrier, different from Preparation Example 1, is that after the hydrothermal crystallization treatment is completed, it is converted into H type through NH4Cl ion exchange; wherein the concentration of the NH4Cl solution used is 0.6 mol / L, the temperature is 65℃, and the time is 1.8h.

[0077] Example 1

[0078] A hydrogen isomerization catalyst, the components contained therein and the corresponding weight parts are shown in Table 1, and is prepared by the following steps:

[0079] (1) Preparing raw materials containing a molecular sieve carrier, a salt solution containing an active metal and an auxiliary metal agent as required for preparation;

[0080] (2) Co-impregnating the salt solution containing the active metal and the auxiliary metal agent into the molecular sieve carrier by equal volume impregnation, impregnating the single salt solution for 50 min, performing vacuum degassing treatment (-0.08 MPa, 30 min) between the steps of impregnation, then drying at 120°C for 6 h, and reducing by hydrogen at 400°C for 4 h to obtain a hydroisomerization catalyst.

[0081] Note: The molecular sieve carrier is obtained in Preparation Example 1; in the oxide containing the active metal, the active metal composition of the raw materials used and the corresponding weight parts are shown in Table 2, wherein the platinum-palladium combination is composed of platinum and palladium in a weight ratio of 1:1, the molybdenum-tungsten combination is composed of molybdenum and tungsten in a weight ratio of 3:1, and the nickel-cobalt combination is composed of nickel and cobalt in a weight ratio of 2:1. In the oxide containing the auxiliary metal, the auxiliary metal is cerium.

[0082] Example 2-3

[0083] A hydroisomerization catalyst, which differs from Example 1 in that the components contained and the corresponding weight parts are shown in Table 1.

[0084] Table 1 Components contained in Examples 1-3 and the corresponding weight parts (parts / kg)

[0085]

[0086] Example 4-5

[0087] A hydroisomerization catalyst, which differs from Example 1 in that the active metal composition of the raw materials used and the corresponding weight parts are shown in Table 2.

[0088] Table 2 Raw materials used for the active metal composition of Examples 1, 4-5 and the corresponding weight parts (parts / kg)

[0089]

[0090] Example 6

[0091] A hydroisomerization catalyst, which differs from Example 1 in that the platinum-palladium combination is composed of platinum and palladium in a weight ratio of.9:1, the molybdenum-tungsten combination is composed of molybdenum and tungsten in a weight ratio of 2.8:1, and the nickel-cobalt combination is composed of nickel and cobalt in a weight ratio of 2.2:1.

[0092] Example 7

[0093] A hydroisomerization catalyst, which differs from Example 1 in that the platinum palladium combination consists of platinum and palladium in a weight ratio of 1.1 : 1, the molybdenum tungsten combination consists of molybdenum and tungsten in a weight ratio of 3.2: 1, and the nickel cobalt combination consists of nickel and cobalt in a weight ratio of 2.2: 1.

[0094] Example 8

[0095] A hydroisomerization catalyst, which differs from Example 1 in that the molecular sieve support is obtained in Preparatory Example 2.

[0096] Example 9

[0097] A hydroisomerization catalyst, which differs from Example 1 in that the molecular sieve support is obtained in Preparatory Example 3.

[0098] Example 10

[0099] A hydroisomerization catalyst, which differs from Example 1 in that the molecular sieve support is obtained in Preparatory Example 4.

[0100] Example 11

[0101] A hydroisomerization catalyst, which differs from Example 1 in that the molecular sieve support is obtained in Preparatory Example 5.

[0102] Example 12

[0103] A hydroisomerization catalyst, which differs from Example 1 in that the molecular sieve support is obtained in Preparatory Example 6.

[0104] Example 13

[0105] A hydroisomerization catalyst, which differs from Example 1 in that the molecular sieve support is obtained in Preparatory Example 7.

[0106] Example 14

[0107] A hydroisomerization catalyst, which differs from Example 1 in that the molecular sieve support is obtained in Preparatory Example 8.

[0108] Example 15

[0109] A hydroisomerization catalyst, which differs from Example 1 in that the molecular sieve support is obtained in Preparatory Example 9.

[0110] Example 16

[0111] A hydroisomerization catalyst, which differs from Example 1 in that the molecular sieve support is obtained in Preparatory Example 10.

[0112] Example 17

[0113] A hydroisomerization catalyst, which differs from Example 1 in that a platinum-palladium combination is not used in the active metal.

[0114] Example 18

[0115] A hydroisomerization catalyst, which differs from Example 1 in that a molybdenum-tungsten combination is not used in the active metal.

[0116] Example 19

[0117] A hydroisomerization catalyst, which differs from Example 1 in that a nickel-cobalt combination is not used in the active metal.

[0118] Example 20

[0119] A hydroisomerization catalyst, which differs from Example 1 in that a platinum-palladium combination, a nickel-cobalt combination is not used in the active metal.

[0120] Example 21

[0121] A hydroisomerization catalyst, which differs from Example 1 in that a platinum-palladium combination, a molybdenum-tungsten combination is not used in the active metal.

[0122] Example 22

[0123] A hydroisomerization catalyst, which differs from Example 1 in that a molybdenum-tungsten combination, a nickel-cobalt combination is not used in the active metal.

[0124] Comparative Example 1

[0125] A hydroisomerization catalyst, which differs from Example 1 in that the component does not contain an oxide containing a promoter metal.

[0126] Comparative Example 2

[0127] A hydroisomerization catalyst, which differs from Example 1 in that the molecular sieve carrier uses ZSM-5 as the carrier.

[0128] Comparative Example 3

[0129] A hydroisomerization catalyst, which differs from Example 1 in that a commercial Ni / Al2O3 catalyst is selected, which is purchased from Shandong Dengzhuo Chemical Co., Ltd., and the product number is DC-2.

[0130] Performance detection test

[0131] Test samples: The hydroisomerization catalysts obtained in Examples 1-22 are selected as test samples 1-22, and the hydroisomerization catalysts obtained in Comparative Examples 1-3 are selected as control samples 1-3.

[0132] Test method: The hydroisomerization catalysts are tested for application, and the reaction conditions are as follows:

[0133] The raw oil was waste cooking oil (acid value 5.6 mgKOH / g, water content 2000 ppm, oxygen content 8.5 wt%);

[0134] The mass ratio of catalyst to raw oil was 1:120;

[0135] The reaction conditions were temperature 320℃, pressure 4.5 MPa, hydrogen to oil ratio 800:1, and space velocity 2 h⁻¹.

[0136] (1) Conversion rate test / selectivity test: GC-MS analysis (ASTM D7798);

[0137] (2) Water and oxygen resistance test: activity retention rate (%) after cyclic injection of water (5000 ppm) / oxygen (5 vol%);

[0138] (3) Life test: deactivation rate (%) after continuous operation at 340℃ for 1000 h;

[0139] After the above tests were performed on test samples 1-22 and control sample 1-3, the test results were recorded in Table 3.

[0140] Table 3 Test results of test samples 1-22 and control sample 1-3

[0141]

[0142] In combination with Example 1 and Comparative Examples 1-3 and in combination with Table 3, it can be seen that, by using the specially prepared molecular sieve carrier, the combination of platinum and palladium, the combination of molybdenum and tungsten, and the combination of nickel and cobalt as active metals, and in combination with the auxiliary metal, the obtained hydrogen isomerization catalyst can realize the synergistic improvement of conversion rate, selectivity, and water and oxygen resistance, and can significantly enhance the overall application effect and service life. If the auxiliary metal is not used or the molecular sieve carrier is replaced by ZSM-5, the conversion rate (%), selectivity (%), activity retention rate (%), and 1000 h deactivation rate (%) obtained by the above tests will all show a large loss. It is also found that the hydrogen isomerization catalyst obtained by the present application has a greater improvement in the above product performance compared with the commercially available catalyst.

[0143] In combination with Example 1 and Examples 14-16 and in combination with Table 3, it can be seen that, after the hydrothermal crystallization treatment is completed, the molecular sieve carrier is converted into H type by NH4Cl ion exchange, which can precisely control the proton replacement efficiency and the skeleton stability, realize the efficient construction of the molecular sieve acid site and the protection of the structural integrity, and thus the hydrogen isomerization catalyst prepared therefrom can have improved performance in conversion rate (%), selectivity (%), activity retention rate (%), and 1000 h deactivation rate (%).

[0144] As can be seen in combination of Embodiment 1 and Embodiments 17-22 and in combination of Table 3, the platinum-palladium combination, the molybdenum-tungsten combination and the nickel-cobalt combination are applied as active metals in the above-mentioned weight parts, a compounded action system of “platinum-palladium activation-molybdenum-tungsten sulfur resistance guarantee-nickel-cobalt diffusion optimization” is formed, and a hydrogen isomerization catalyst with better quality can be obtained; if any one or two of the platinum-palladium combination, the molybdenum-tungsten combination and the nickel-cobalt combination is applied as active metals, it is found that the corresponding effect brought by the same is far inferior to the corresponding effect brought by the synergy of the three; thus, it can be seen that the ternary synergy of the platinum-palladium combination, the molybdenum-tungsten combination and the nickel-cobalt combination can ensure that the hydrogen isomerization catalyst finally obtained realizes the synergistic consideration and promotion of conversion rate, selectivity and water oxygen resistance when applied, and brings significant enhancement in service life.

[0145] The specific embodiments are only an explanation of the present application, and are not a limitation of the present application, and those skilled in the art can make modifications to the embodiments without creative contribution after reading the present specification, but as long as the modifications are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A hydroisomerization catalyst characterized in that, The components include the following parts by weight: Molecular sieve carrier 97.5-99.4 parts; Active metal-containing oxide 0.5-1.5 parts; Auxiliary metal-containing oxide 0.1-1.0 parts; The molecular sieve carrier is synthesized by using double templates; The active metal in the active metal-containing oxide is composed of the following components by weight: Platinum-palladium combination 0.4-0.8 parts; ‌Molybdenum-tungsten combination 0.3-0.6 parts; Nickel-cobalt combination 0.1-0.4 parts; The auxiliary metal in the auxiliary metal-containing oxide is cerium; The platinum-palladium combination is composed of platinum and palladium in a weight ratio of (0.9-1.1):1; The molybdenum-tungsten combination is composed of molybdenum and tungsten in a weight ratio of (2.8-3.2):1; The nickel-cobalt combination is composed of nickel and cobalt in a weight ratio of (1.8-2.2):1; The molecular sieve carrier is prepared by the following steps: The silicon source, aluminum source, and double templates are dissolved in water, the pH is adjusted to 10-11, and then hydrothermal crystallization treatment is performed, followed by washing, drying, and calcination to obtain the molecular sieve carrier; The temperature of the hydrothermal crystallization treatment is 160-180℃, and the time is 68-76h; the calcination temperature is 540-560℃, and the calcination time is 5-6h; The ditemplate consists of C6H 14 Br2and TEAOH in a molar ratio of 1 : (2-4).

2. The hydroisomerization catalyst of claim 1, wherein: After completing the hydrothermal crystallization treatment, ion exchange conversion to H type is performed by using NH4Cl; the concentration of the NH4Cl solution used is 0.4-0.6 mol / L, the temperature is 55-65℃, and the time is 1.8-2.2h.

3. The hydroisomerization catalyst of claim 1, wherein: The molecular sieve carrier has three-dimensional ten-membered ring cross channels, is 0.54*0.56 nm straight channel and 0.52*0.58 nm Z-shaped channel, and has a specific surface area of 150-230 m 2 / g, and a total acid amount of 0.9-2.8 mmol / g.

4. Process for the preparation of a hydroisomerisation catalyst according to any one of claims 1 to 3, characterised in that: The steps include: (1) Preparing raw materials including a molecular sieve carrier, a salt solution containing active metal and auxiliary metal according to the preparation requirements; (2) Co-impregnating the salt solution containing active metal and auxiliary metal in the molecular sieve carrier, drying, and then hydrogen reduction to obtain a hydroisomerization catalyst.

5. The use of the hydroisomerization catalyst according to any one of claims 1-3 in the production of biodiesel and biojet fuel.

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