A catalyst for selective hydrogenation of benzene ring and its preparation method and application

Abstract

The application discloses a benzene ring selective hydrogenation catalyst, which comprises a carrier and an active component loaded on the surface of the carrier. The carrier is a titanium dioxide carrier modified by one or more of iron, silver, copper, fluorine, sulfur and carbon; and the active component is ruthenium and / or cobalt. The application adopts the doped titanium dioxide to load ruthenium-cobalt, and the catalyst has good catalytic performance and stability. In the repeated use process, the performance is stable. Meanwhile, the catalyst is used for the preparation of 4,4-diamino dicyclohexyl methane, the selectivity of the catalyst for the required 4,4-diamino dicyclohexyl methane is higher, and the catalyst has higher practicability. In addition, the application limits the amount of each component in the catalyst and the temperature and time of aging, calcination and reduction, so that the ruthenium-cobalt active component is fully loaded on the doped titanium dioxide, and the prepared catalyst has good catalytic performance.

Description

TECHNICAL FIELD

[0001] The present application relates to a catalyst, in particular to a benzene ring selective hydrogenation catalyst and its preparation method and application, belonging to the field of chemical industry. BACKGROUND

[0002] 4,4-diaminodicyclohexyl methane, referred to as HMDA, is colorless or slightly yellow viscous or white waxy substance, easily soluble in toluene, petroleum ether, ethanol, tetrahydrofuran, etc., is an important organic intermediate in the production of polyurethane and polyamide, and is generally prepared by liquid phase catalytic hydrogenation of diamino diphenyl methane (MDA).

[0003] US patent US3856862 discloses a high-efficiency MDA hydrogenation process catalyzed by Rh. It uses Rh / Al2O3 supported catalyst to carry out MDA hydrogenation reaction at high temperature and high pressure. After the reaction, the Rh catalyst and the product are separated by filtration, and then 0.5-5% O2 and N2 gas flow is continuously introduced, and the catalyst is activated at 300-450℃ for 2-6h, and then the catalyst regeneration is completed.

[0004] Chinese patent CN101966456A discloses a hydrogenation catalyst and a method for preparing 4,4-diaminodicyclohexyl methane. It mentions that a MDA hydrogenation catalyst is a single metal ruthenium / mesoporous carbon catalyst with a ruthenium content of 0.5-10%, which needs high-temperature calcination for preparation, but ruthenium is easy to agglomerate, which affects the performance of the catalyst. Allen discloses a method for preparing PACM, which uses alumina-supported ruthenium as catalyst, and the loading amount of ruthenium is 5%. The catalyst is modified by nitrate, sulfate, alkali metal and alkaline earth metal compounds. Under the conditions of 100-300℃ and greater than 3.5 MPa, fatty alcohol or ammonia is added as an additive.

[0005] US patent US20060047173 uses MDA-85 as raw material, first pretreats it in a ruthenium-loaded fixed-bed catalyst, then cools it to 100-130℃, and carries out aromatic ring hydrogenation reaction in a rhodium / ruthenium mixed-loaded catalyst. The HMDA yield of this method is less than 90%.

[0006] In the prior art, there are the following problems: 1. The catalyst preparation process is complex, the catalyst dosage is large, and the investment cost is high. In addition, under the condition of batch process, the large catalyst dosage may cause long filtration time of the reaction mother liquor, etc., affecting the production efficiency; 2. The reaction substrate concentration is low, causing low production efficiency of the unit volume reactor, high solvent separation energy consumption, and increased production cost; 3. The reaction condition is harsh. In order to improve the yield of 4,4-diamino dicyclohexyl methane, the catalyst is modified by using inorganic alkali, and the hydrogenation reaction is carried out at high temperature and high pressure, which has high safety risk and is easy to cause material leakage and environmental pollution; 4. The catalyst reported in the patent has poor catalytic hydrogenation effect, poor selectivity, and low yield when applied to the preparation of HMDA from MDA. SUMMARY

[0007] In view of the problems of complex catalyst preparation process, poor catalytic hydrogenation effect, poor selectivity, and harsh reaction condition for preparing HMDA in the prior art, the present application provides a benzene ring selective hydrogenation catalyst. The titanium dioxide carrier is modified by doping with metal or non-metal ions, and ruthenium and / or cobalt are loaded on the carrier as active components. The modified titanium dioxide carrier has better loading effect, and the catalyst has more cycle times. The synergistic effect between ruthenium and cobalt has high selectivity for preparing 4,4-diamino dicyclohexyl methane from 4,4-diamino diphenyl methane, and the yield of 4,4-diamino dicyclohexyl methane is high.

[0008] According to a first embodiment of the present application, a benzene ring selective hydrogenation catalyst is provided.

[0009] A benzene ring selective hydrogenation catalyst, which comprises a carrier and an active component loaded on the surface of the carrier; wherein the carrier is a titanium dioxide carrier modified by one or more elements of iron, silver, copper, fluorine, sulfur, and carbon; and the active component is ruthenium and / or cobalt.

[0010] Preferably, the carrier is a titanium dioxide carrier doped with iron.

[0011] Preferably, the active component is a composite material of ruthenium doped with cobalt.

[0012] Preferably, the mass of the active component is 0.5% to 15% of the carrier, preferably 1% to 10%, further preferably 3% to 7%, and more preferably 4% to 6%. For example, 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, 10%, 10.5%, 11%, 11.5%, 12%, 12.5%, 13%, 13.5%, 14%, 14.5%, or 15%.

[0013] Preferably, the mass of the modifying element on the carrier is 0.5% to 10% of the carrier, preferably 1% to 8%, further preferably 2% to 7%, and more preferably 4% to 6%. For example, 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, 10%.

[0014] Preferably, the mass ratio of cobalt to ruthenium in the active component is 1:1 to 2, and preferably 1:1.5 to 1.8. For example, 1:1, 1:1.1, 1:1.2, 1:1.3, 1:1.4, 1:1.5, 1:1.6, 1:1.7, 1:1.8, 1:1.9, 1:2.

[0015] According to a second embodiment of the present application, a method for preparing a benzene ring selective hydrogenation catalyst is provided.

[0016] A method for preparing a benzene ring selective hydrogenation catalyst, the method comprising the following steps:

[0017] 1) mixing a precursor of a doping element with a titanium precursor, stirring, separating, drying and calcining the obtained solid to obtain a doped titanium dioxide carrier;

[0018] 2) placing the doped titanium dioxide carrier obtained in step 1) in a reaction container, adding a solution containing a ruthenium precursor, stirring and adding a cobalt precursor, after aging, centrifuging, separating by extraction, washing, drying and grinding to obtain a powdery solid;

[0019] 3) calcining the powdery solid obtained in step 2), reducing with a reducing gas under an oxygen-free condition, and after the reduction is completed, lowering to room temperature to obtain a benzene ring selective hydrogenation catalyst.

[0020] Preferably, the precursor of the doping element in step 1) is a precursor of any one of iron, silver, copper, fluorine, sulfur and carbon, and preferably a precursor of iron, and preferably ferric nitrate.

[0021] Preferably, the titanium precursor in step 1) is one or both of a tetrabutyl titanate n-butanol solution and a tetraethyl orthosilicate ethanol solution, and preferably a tetrabutyl titanate n-butanol solution; as a preference, the preparation method of the tetrabutyl titanate n-butanol solution is: mixing tetrabutyl titanate and n-butanol at a mass ratio of 10:0.5 to 1, stirring and mixing for 1 to 6 hours (preferably 3 to 5 hours) to obtain the tetrabutyl titanate n-butanol solution.

[0022] Preferably, the mass ratio of the precursor of the doping element to the tetrabutyl titanate n-butanol solution in step 1) is 1:3 to 8, and preferably 1:4 to 6.

[0023] Preferably, the stirring speed in step 1) is 300-1000 rpm, preferably 400-800 rpm.

[0024] Preferably, the stirring time in step 1) is 1-10 h, preferably 2-8 h.

[0025] Preferably, the drying temperature in step 1) is 60-120 °C, preferably 70-110 °C.

[0026] Preferably, the drying time in step 1) is 8-24 h, preferably 12-20 h.

[0027] Preferably, the calcination temperature in step 1) is 250-450 °C, preferably 300-400 °C.

[0028] Preferably, the calcination time in step 1) is 1-6 h, preferably 2-5 h.

[0029] Preferably, the cobalt precursor in step 2) is cobalt nitrate hexahydrate.

[0030] Preferably, the ruthenium precursor in step 2) is ruthenium trichloride in n-propanol solution.

[0031] Preferably, the solid-liquid ratio of the doped titanium dioxide carrier to the solution containing the ruthenium precursor in step 2) is 1:3-15, preferably 1:5-12.

[0032] Preferably, the mass ratio of the cobalt precursor to the ruthenium precursor in step 2) is 1:0.42-0.83, preferably 1:0.63-0.75.

[0033] Preferably, the stirring temperature in step 2) is 25-65 °C, preferably 35-55 °C.

[0034] Preferably, the stirring time in step 2) is 2-6 h, preferably 3-5 h.

[0035] Preferably, the aging time in step 2) is 6-20 h, preferably 10-16 h.

[0036] Preferably, the reagent used for extraction in step 2) is deionized water or anhydrous ethanol.

[0037] Preferably, the calcination temperature in step 3) is 300-500 °C, preferably 350-450 °C.

[0038] Preferably, the calcination time in step 3) is 2-8 h, preferably 4-6 h.

[0039] Preferably, the reducing gas in step 3) is hydrogen.

[0040] Preferably, the temperature of the reduction in step 3) is 200-600℃, preferably 400-550℃.

[0041] Preferably, the time of the reduction in step 3) is 2-6h, preferably 3-5h.

[0042] Preferably, the heating rate of the reduction in step 3) is 4-8℃ / min, preferably 4-6℃ / min.

[0043] Preferably, the preparation method of the solution containing the ruthenium precursor in step 2) is: dissolving a ruthenium-containing compound in solvent I, ultrasonic oscillation and then standing to obtain a solution containing a ruthenium precursor.

[0044] As a preference, the ruthenium-containing compound is one or more of anhydrous ruthenium trichloride, nitrosyl ruthenium nitrate and ruthenium acetate, preferably anhydrous ruthenium trichloride.

[0045] Preferably, the solvent I is n-propanol.

[0046] Preferably, the solid-liquid ratio of the ruthenium-containing compound to solvent I is 5-20g / L, preferably 7-15g / L.

[0047] Preferably, the ultrasonic oscillation time is 30-60min, preferably 40-55min.

[0048] Preferably, the standing time is 2-5h, preferably 3-4h.

[0049] Preferably, step 1) is specifically: mixing any doped element precursor with a titanium precursor, stirring at a speed of 300-1000rpm (preferably 400-800rpm) for 1-10h (preferably 2-8h), after separating the solution, drying the obtained solid at 60-120℃ (preferably 70-110℃) for 8-24h (preferably 12-20h), and then calcining at 250-450℃ (preferably 300-400℃) for 1-6h (preferably 2-5h) to obtain a doped titanium dioxide carrier.

[0050] Preferably, the step 2) is specifically: placing the doped titanium dioxide carrier obtained in step 1) into a reaction container, adding a solution containing a ruthenium precursor in an amount of solid-liquid ratio of 1:3-15 (preferably 1:5-12), adding a cobalt precursor while stirring at 25-65℃ (preferably 35-55℃) for 2-6h (preferably 3-5h), wherein the mass ratio of the cobalt precursor to the ruthenium precursor is 1:0.42-0.83 (preferably 1:0.63-0.75), and then aging the mixed solution at the temperature for 6-20h (preferably 10-16h), and obtaining the mixed solution after the aging, centrifuging, extracting, and washing the obtained mixed solution with deionized water and anhydrous ethanol in sequence, and finally drying the solution, grinding the obtained solid with a mortar to obtain a powdery solid.

[0051] Preferably, the step 3) is specifically: calcining the powdery solid obtained in step 2) at 300-500 (preferably 350-450℃) for 2-8h (preferably 4-6h), obtaining a powder material after the calcination, heating the powder material to 200-600℃ (preferably 400-550℃) under nitrogen protection, and reducing the powder material with hydrogen at the temperature for 2-6h (preferably 3-5h), and then cooling the powder material to room temperature under nitrogen protection, to obtain a benzene ring selective hydrogenation catalyst.

[0052] Preferably, the preparation method of the solution containing a ruthenium precursor in step 2) is: adding anhydrous ruthenium trichloride into n-propanol, with a liquid-solid ratio of 5-20g / L (preferably 7-15g / L), and ultrasonic oscillation for 30-60min (preferably 40-55min), and then transferring the solution to a volumetric flask, inverting the volumetric flask up and down for 3-6 times, and then standing for 2-5h (preferably 3-4h), and finally using solvent I to make up the volume, to obtain the solution containing a ruthenium precursor.

[0053] According to a third embodiment of the present application, a preparation method of 4,4-diamino-dicyclohexylmethane is provided.

[0054] A preparation method of 4,4-diamino-dicyclohexylmethane, comprising the following steps:

[0055] A) adding a benzene ring selective hydrogenation catalyst, solvent II, and 4,4-diamino-diphenylmethane into a reaction container, introducing hydrogen into the reaction container under air isolation, and heating and pressurizing, stirring the reaction, filtering the mixture after the reaction, and obtaining 4,4-diamino-dicyclohexylmethane.

[0056] In the present application, the introduction of hydrogen is specifically: replacing the air in the kettle with nitrogen for 3-6 times, vacuumizing the kettle by a vacuum pump, introducing hydrogen into the reaction kettle through a hydrogen pipeline and a hydrogen pressure reducing valve, heating to 60-140℃, and pressurizing to 0.5-4Mpa.

[0057] Preferably, the solvent II in step A) is one of tetrahydrofuran, 1,4-dioxane, dimethyl sulfoxide, preferably tetrahydrofuran.

[0058] Preferably, the temperature of the heating in step A) is 60-140℃, preferably 80-120℃.

[0059] Preferably, the pressure of the pressurization in step A) is 1-3 Mpa, preferably 1.5-2.5 Mpa.

[0060] Preferably, the time of the stirring reaction in step A) is 1-5 h, preferably 2-4 h.

[0061] Preferably, the stirring speed of the stirring reaction in step A) is 200-800 rpm, preferably 300-700 rpm.

[0062] Preferably, the amount of the benzene ring selective catalyst added in step A) is 2-25% of the mass of 4,4-diaminodiphenylmethane, preferably 6-15%.

[0063] Preferably, the step A) is specifically: the benzene ring selective hydrogenation catalyst, tetrahydrofuran and 4,4-diaminodiphenylmethane are added to a high-pressure reaction kettle, after putting in a magnetic stirrer, the reaction kettle is sealed, the air in the kettle is replaced with nitrogen for 3-6 times (preferably 4-5 times), then the reaction kettle is pumped to vacuum, then the reaction kettle is heated to 60-140℃ (preferably 80-120℃), and hydrogen is introduced to pressurize to 0.5-4 Mpa (preferably 1.5-2.5 Mpa), under the stirring speed of 200-800 rpm (preferably 300-700 rpm), the reaction is carried out for 1-5 h (preferably 2-4 h), after the reaction is completed, filtration is carried out, and 4,4-diaminodicyclohexylmethane is obtained.

[0064] In the present application, any one or more elements of iron, silver, copper, sulfur, fluorine, carbon are used to dope and modify titanium dioxide, compared with the undoped titanium dioxide carrier, the doped titanium dioxide carrier provided by the present application has larger specific surface area, and the loaded active components are more stable. At the same time, after the metal or non-metal doping, ruthenium and / or cobalt are loaded on the titanium dioxide carrier, preferably the modified cobalt oxide is loaded with ruthenium, after the modification of cobalt and ruthenium, the selectivity of the catalyst to HMDA in the hydrogenation reaction of 4,4-diaminodiphenylmethane is higher. Preferably, the present application uses iron-doped titanium dioxide, because the iron ions provide alkaline sites, so that it is not necessary to add an alkaline solution during the preparation of the catalyst, and the combination with the ruthenium-modified cobalt oxide is also more stable, so that the finished catalyst has better catalytic performance and stability, and does not affect its performance during repeated use, while improving the yield of the product and the selectivity to HMDA.

[0065] In the present application, the preparation process of the benzene ring selective hydrogenation catalyst is further limited. First, a ruthenium precursor is prepared with a ruthenium-containing compound, and a metal or non-metal is doped into the titanium dioxide. Then, the ruthenium precursor, the doped titanium dioxide, and a cobalt precursor are mixed to prepare the benzene ring selective hydrogenation catalyst. In the process of mixing the ruthenium precursor, the doped titanium dioxide carrier, and the cobalt precursor to prepare the catalyst, the steps of aging, calcination, and reduction are required, and the optimal aging temperature is set to 25-65°C (for example, 25°C, 26°C, 28°C, 30°C, 33°C, 36°C, 39°C, 42°C, 45°C, 48°C, 50°C, 52°C, 54°C, 56°C, 58°C, 60°C, 62°C, 63°C, 64°C, 65°C), the aging time is 6-20h (for example, 6h, 7h, 8h, 9h, 10h, 14h, 16h, 17h, 18h, 19h, 20h), the calcination temperature is 300-500°C (for example, 300°C, 310°C, 330°C, 350°C, 380°C, 420°C, 440°C, 450°C, 460°C, 470°C, 480°C, 490°C, 500°C), the calcination time is 2-8h (for example, 2h, 3h, 4h, 5h, 6h, 7h, 8h), the reduction temperature is 200-600°C (for example, 200°C, 220°C, 240°C, 260°C, 300°C, 340°C, 380°C, 420°C, 460°C, 500°C, 530°C, 550°C, 580°C, 600°C), and the reduction time is 2-6h (for example, 2h, 3h, 4h, 5h, 6h). In addition, the temperature rising speed during the reduction process is limited to 4-8°C / min. Under the above conditions, the benzene ring selective hydrogenation catalyst is prepared, which can fully combine the ruthenium-modified cobalt oxide on the doped titanium dioxide carrier, improve the loading rate, and further enhance the catalytic performance and stability of the catalyst.

[0066] In the present application, the amount of each compound used in the catalyst preparation process is strictly limited. The solid-liquid ratio of the doped titanium dioxide to the liquid (i.e., the solution containing the ruthenium precursor) is 1:3-15 (preferably 1:5-12), and the mass ratio of the cobalt precursor to the ruthenium precursor is 1:0.42-0.83 (preferably 1:0.63-0.75). Within the above range, the modification effect of ruthenium on cobalt is optimal, and the active component loaded on the titanium dioxide carrier has higher activity, higher loading success rate, and stronger stability.

[0067] In the present application, in the process of preparing 4,4-diamino-dicyclohexyl methane from 4,4-diamino-diphenyl methane, the benzene ring selective hydrogenation catalyst provided by the present application has high selectivity to HMDA, and the yield is improved. Preferably, during use, the amount of catalyst added is controlled to be 2-25% (for example 2%, 3%, 4%, 6%, 8%, 10%, 12%, 15%, 16%, 18%, 20%, 21%, 22%, 23%, 24%, 25%) of the mass of 4,4-diamino-diphenyl methane. In addition, the benzene ring selective hydrogenation catalyst prepared by the present application does not need to add a basic additive (such as lithium hydroxide, potassium hydroxide, etc.) to inhibit equipment wear compared with other catalysts, and at the same time, the conditions of the catalytic reaction are more mild, and the hydrogenation performance is better.

[0068] In the present application, cobalt-ruthenium is used as the active component and is supported on doped titanium dioxide, which is more inexpensive than existing ruthenium-rhodium, rhodium, ruthenium, etc. catalysts, and has higher selectivity to 4,4-diamino-dicyclohexyl methane during the reaction process.

[0069] Compared with the prior art, the present application has the following beneficial effects:

[0070] 1. The benzene ring selective hydrogenation catalyst provided by the present application uses doped titanium dioxide to support ruthenium-cobalt, and the catalyst has good catalytic performance and stability, and at the same time has higher selectivity to the required 4,4-diamino-dicyclohexyl methane, and has high practicability.

[0071] 2. The preparation method of the benzene ring selective hydrogenation catalyst provided by the present application is simple, and at the same time, the amount of each component and the temperature and time of aging, calcination and reduction are strictly limited, so that the ruthenium-cobalt active component is fully supported on the doped titanium dioxide, and the prepared catalyst has good catalytic performance.

[0072] 3. The preparation method of 4,4-diamino-dicyclohexyl methane provided by the present application, through the benzene ring selective hydrogenation catalyst and the limitation of the amount thereof and the suitable hydrogenation temperature and time, has great help for preparing high-purity 4,4-diamino-dicyclohexyl methane. BRIEF DESCRIPTION OF DRAWINGS

[0073] Figure 1 The TEM image of the benzene ring selective hydrogenation catalyst provided by the present application. DETAILED DESCRIPTION

[0074] The technical solutions of the present application are illustrated below, and the scope of protection requested by the present application includes but is not limited to the following embodiments.

[0075] According to a first embodiment of the present application, a benzene ring selective hydrogenation catalyst is provided.

[0076] A benzene ring selective hydrogenation catalyst, which comprises a carrier and an active component supported on the surface of the carrier; wherein the carrier is a titanium dioxide carrier modified by one or more elements of iron, silver, copper, fluorine, sulfur, and carbon; and the active component is ruthenium and / or cobalt.

[0077] Preferably, the carrier is a titanium dioxide carrier doped with iron.

[0078] Preferably, the active component is a composite of ruthenium modified by cobalt doping.

[0079] Preferably, the mass of the active component is 0.5% to 15% of the carrier, preferably 1% to 10%, further preferably 3% to 7%, and more preferably 4% to 6%.

[0080] Preferably, the mass of the modified element on the carrier is 0.5% to 10% of the carrier, preferably 1% to 8%, further preferably 2% to 7%, and more preferably 4% to 6%.

[0081] Preferably, the mass ratio of cobalt to ruthenium in the active component is 1:1 to 2, preferably 1:1.5 to 1.8.

[0082] According to a second embodiment of the present application, a preparation method of a benzene ring selective hydrogenation catalyst is provided.

[0083] A preparation method of a benzene ring selective hydrogenation catalyst, which comprises the following steps:

[0084] 1) mixing a precursor of a doping element with a titanium precursor, stirring, separating, drying and calcining the obtained solid to obtain a doped titanium dioxide carrier;

[0085] 2) placing the doped titanium dioxide carrier obtained in step 1) in a reaction container, adding a ruthenium precursor, stirring and adding a cobalt precursor, after aging, centrifuging, extracting and separating, washing, drying, and grinding to obtain a powdery solid;

[0086] 3) calcining the powdery solid obtained in step 2), reducing with a reducing gas under the condition of oxygen isolation, and after the reduction is completed, lowering to room temperature to obtain a benzene ring selective hydrogenation catalyst.

[0087] Preferably, the precursor of the doping element in step 1) is a precursor of any one of iron, silver, copper, fluorine, sulfur, and carbon, preferably a precursor of iron, and preferably ferric nitrate.

[0088] Preferably, the titanium precursor in step 1) is one or both of a tetrabutyl titanate n-butanol solution and a tetraethyl orthosilicate ethanol solution, preferably a tetrabutyl titanate n-butanol solution; preferably, the tetrabutyl titanate n-butanol solution is prepared by mixing tetrabutyl titanate and n-butanol at a mass ratio of 10:0.5-1, stirring and mixing for 1-6 h (preferably 3-5 h) to obtain the tetrabutyl titanate n-butanol solution.

[0089] Preferably, the mass ratio of the doped element precursor to the tetrabutyl titanate n-butanol solution in step 1) is 1:3-8, preferably 1:4-6.

[0090] Preferably, the stirring speed in step 1) is 300-1000 rpm, preferably 400-800 rpm.

[0091] Preferably, the stirring time in step 1) is 1-10 h, preferably 2-8 h.

[0092] Preferably, the drying temperature in step 1) is 60-120°C, preferably 70-110°C.

[0093] Preferably, the drying time in step 1) is 8-24 h, preferably 12-20 h.

[0094] Preferably, the calcination temperature in step 1) is 250-450°C, preferably 300-400°C.

[0095] Preferably, the calcination time in step 1) is 1-6 h, preferably 2-5 h.

[0096] Preferably, the cobalt precursor in step 2) is cobalt nitrate hexahydrate.

[0097] Preferably, the ruthenium precursor in step 2) is ruthenium trichloride n-propanol solution.

[0098] Preferably, the solid-liquid ratio of the doped titanium dioxide carrier to the ruthenium precursor in step 2) is 1:3-15, preferably 1:5-12.

[0099] Preferably, the mass ratio of the cobalt precursor to the ruthenium precursor in step 2) is 1:0.42-0.83, preferably 1:0.63-0.75.

[0100] Preferably, the stirring temperature in step 2) is 25-65°C, preferably 35-55°C.

[0101] Preferably, the stirring time in step 2) is 2-6 h, preferably 3-5 h.

[0102] Preferably, the aging time of step 2) is 6-20h, preferably 10-16h.

[0103] Preferably, the reagent used in the extraction of step 2) is deionized water or anhydrous ethanol.

[0104] Preferably, the roasting temperature of step 3) is 300-500℃, preferably 350-450℃.

[0105] Preferably, the roasting time of step 3) is 2-8h, preferably 4-6h.

[0106] Preferably, the reducing gas of step 3) is hydrogen.

[0107] Preferably, the reduction temperature of step 3) is 200-600℃, preferably 400-550℃.

[0108] Preferably, the reduction time of step 3) is 2-6h, preferably 3-5h.

[0109] Preferably, the heating rate of the reduction of step 3) is 4-8℃ / min, preferably 4-6℃ / min.

[0110] Preferably, the preparation method of the ruthenium precursor of step 2) is: dissolving a ruthenium-containing compound in solvent I, ultrasonic oscillation, and then standing to obtain the precursor of ruthenium;

[0111] As a preferred, the ruthenium-containing compound is one or more of anhydrous ruthenium trichloride, nitrosyl ruthenium nitrate and ruthenium acetate, preferably anhydrous ruthenium trichloride.

[0112] Preferably, the solvent I is n-propanol.

[0113] Preferably, the solid-liquid ratio of the ruthenium-containing compound to solvent I is 5-20g / L, preferably 7-15g / L.

[0114] Preferably, the ultrasonic oscillation time is 30-60min, preferably 40-55min.

[0115] Preferably, the standing time is 2-5h, preferably 3-4h.

[0116] Preferably, the step 1) is specifically mixing any one of the doped element precursor with the titanium precursor, stirring at a speed of 300-1000 rpm (preferably 400-800 rpm) for 1-10 h (preferably 2-8 h), drying the obtained solid at 60-120 °C (preferably 70-110 °C) for 8-24 h (preferably 12-20 h) after separating the solution, and calcining at 250-450 °C (preferably 300-400 °C) for 1-6 h (preferably 2-5 h) to obtain the doped titanium dioxide carrier.

[0117] Preferably, the step 2) is specifically placing the doped titanium dioxide carrier obtained in step 1) into a reaction container, adding the ruthenium precursor prepared in step 1) in an amount of solid-liquid ratio of 1:3-15 (preferably 1:5-12), adding the cobalt precursor while stirring at 25-65 °C (preferably 35-55 °C) for 2-6 h (preferably 3-5 h), wherein the mass ratio of the cobalt precursor to the ruthenium precursor is 1:0.42-0.83 (preferably 1:0.63-0.75), and then aging the mixed solution at the temperature for 6-20 h (preferably 10-16 h) to obtain a mixed solution, centrifuging, extracting, and washing the obtained mixed solution with deionized water and anhydrous ethanol in sequence, and finally drying the solution to obtain a solid, which is ground with a mortar to obtain a powdery solid.

[0118] Preferably, the step 3) is specifically calcining the powdery solid obtained in step 2) at 300-500 °C (preferably 350-450 °C) for 2-8 h (preferably 4-6 h) to obtain a powder material, heating the powder material to 200-600 °C (preferably 400-550 °C) under nitrogen protection, and reducing the powder material with hydrogen at the temperature for 2-6 h (preferably 3-5 h), and then cooling the powder material to room temperature under nitrogen protection to obtain a benzene ring selective hydrogenation catalyst.

[0119] Preferably, the preparation method of the ruthenium precursor in step 2) is specifically adding anhydrous ruthenium trichloride into n-propanol at a liquid-solid ratio of 5-20 g / L (preferably 7-15 g / L), ultrasonic oscillation for 30-60 min (preferably 40-55 min), transferring the solution to a volumetric flask after the oscillation, inverting the volumetric flask up and down for 3-6 times, and then standing for 2-5 h (preferably 3-4 h), and finally constant volume with n-propanol to obtain the ruthenium precursor.

[0120] According to a third embodiment of the present application, a preparation method of 4,4-diaminodicyclohexyl methane is provided.

[0121] A preparation method of 4,4-diaminodicyclohexyl methane, the method comprising the following steps:

[0122] A) adding a selective hydrogenation catalyst for benzene ring, a solvent II and 4, 4-diaminodiphenylmethane into a reaction container, introducing hydrogen into the reaction container under air isolation conditions and heating and pressurizing, stirring the reaction, filtering the mixture after the reaction is completed, and obtaining 4, 4-diaminodicyclohexylmethane.

[0123] Preferably, the solvent II in step A) is one of tetrahydrofuran, 1, 4-dioxane, dimethyl sulfoxide, preferably tetrahydrofuran.

[0124] Preferably, the temperature of the heating in step A) is 60-140℃, preferably 80-120℃.

[0125] Preferably, the pressure of the pressurizing in step A) is 1-3 Mpa, preferably 1.5-2.5 Mpa.

[0126] Preferably, the time of the stirring reaction in step A) is 1-5 h, preferably 2-4 h.

[0127] Preferably, the stirring speed of the stirring reaction in step A) is 200-800 rpm, preferably 300-700 rpm.

[0128] Preferably, the amount of the selective catalyst added in step A) is 2-25% of the mass of 4, 4-diaminodiphenylmethane, preferably 6-15%.

[0129] Preferably, step A) is specifically: adding a selective hydrogenation catalyst for benzene ring, tetrahydrofuran and 4, 4-diaminodiphenylmethane into a high-pressure reaction kettle, placing a magnetic stirrer into the kettle, sealing the kettle, replacing the air in the kettle with nitrogen for 3-6 times (preferably 4-5 times), then vacuumizing the kettle, heating the kettle to 60-140℃ (preferably 80-120℃), introducing hydrogen to pressurize to 0.5-4 Mpa (preferably 1.5-2.5 Mpa), stirring at a speed of 200-800 rpm (preferably 300-700 rpm) for 1-5 h (preferably 2-4 h), and filtering after the reaction is completed to obtain 4, 4-diaminodicyclohexylmethane.

[0130] Preparation Example 1

[0131] 1) Mixing 8 g of ferric nitrate with 40 g of tetrabutyl titanate n-butanol solution and stirring at a speed of 500 rpm for 5 h, separating the solution, drying the obtained solid at 90℃ for 15 h, calcining the dried solid at 350℃ for 3 h, and obtaining 6 g of Fe-TiO2.

[0132] Preferably, the preparation method of the tetrabutyl titanate n-butanol solution is: mixing 37.2 g of tetrabutyl titanate and 2.8 g of n-butanol to obtain 40 g of tetrabutyl titanate n-butanol solution.

[0133] 2) Take 1 g of Fe-TiO2 body obtained in step 1) and place it in a round bottom flask, add 8 mL of ruthenium trichloride n-propanol solution, stir at 45°C for 4h while adding 0.11 g of cobalt nitrate hexahydrate, after stirring, age at 45°C for 12h, after aging, obtain a mixed solution, centrifuge, extract and separate the obtained mixed solution, then wash it with 10 mL of deionized water and 10 mL of anhydrous ethanol for 3 times respectively, finally, place the solution in a vacuum drying oven, vacuum dry at 110°C for 10h, and grind the obtained solid after drying into powder, to obtain 0.93 g of powdery solid.

[0134] The preparation method of the ruthenium trichloride n-propanol solution is as follows: add 1 g of anhydrous ruthenium trichloride and 50 mL of n-propanol in a beaker, ultrasonic oscillation for 50 min, then transfer the solution to a 100 mL volumetric flask, invert the volumetric flask up and down for 5 times, and then stand for 3h, and then use n-propanol to constant volume to 100 mL to obtain the ruthenium trichloride n-propanol solution.

[0135] 3) Calcine the 0.93 g of powdery solid obtained in step 2) at 400°C for 5h, after calcination, place the powdery solid in a quartz boat and put it into a vacuum tube furnace, pass pure nitrogen with a purity of >99.99% at a flow rate of 35 mL / min, increase the temperature to 500°C at a rate of 5°C / min, and reduce it with hydrogen at this temperature for 4h, after reduction, cool it to room temperature under the protection of nitrogen, to obtain 0.75 g of Ru-Co / Fe-TiO2 benzene ring selective hydrogenation catalyst.

[0136] The Ru-Co / Fe-TiO2 benzene ring selective hydrogenation catalyst obtained in step 3) is detected, the mass of the active component is 5.02% of the carrier, the mass ratio of cobalt to ruthenium is 1:1.71, and the mass of Fe on the carrier is 5.01% of the carrier.

[0137] Preparation Example 2

[0138] 1) Mix 7 g of iron nitrate with 38 g of tetrabutyl titanate n-butanol solution, and stir at a speed of 500 rpm for 5h, separate the solution, dry the obtained solid at 80°C for 15h, then calcine the dried solid at 350°C for 3h, to obtain 5.5 g of Fe-TiO2.

[0139] The preparation method of the tetrabutyl titanate n-butanol solution is as follows: mix 35.3 g of tetrabutyl titanate and 2.7 g of n-butanol to obtain 38 g of tetrabutyl titanate n-butanol solution.

[0140] 2) Take 1 g of Fe-TiO2 body obtained in step 1) and place it in a round bottom flask, add 9 mL of ruthenium trichloride n-propanol solution, while stirring at 45°C for 4 h, add 0.13 g of cobalt nitrate hexahydrate, after stirring, age at 45°C for 12 h, after aging, obtain a mixed solution, centrifuge, extract and separate the obtained mixed solution, then wash it with 5 mL of deionized water and 5 mL of anhydrous ethanol for 3 times respectively, finally, place the solution in a vacuum drying oven, vacuum dry at 110°C for 10 h, and grind the obtained solid after drying into powder, to obtain 0.96 g of powdery solid.

[0141] The preparation method of the ruthenium trichloride n-propanol solution is as follows: add 1 g of anhydrous ruthenium trichloride and 50 mL of n-propanol in a beaker, ultrasonic oscillation for 50 min, then transfer the solution to a 100 mL volumetric flask, invert the volumetric flask up and down for 5 times, and then stand for 3 h, and then use n-propanol to constant volume to 100 mL, to obtain the ruthenium trichloride n-propanol solution.

[0142] 3) Calcine the 0.96 g of powdery solid obtained in step 2) at 400°C for 5 h, after calcination, place the powdery solid in a quartz boat, and place it in a vacuum tube furnace, pass pure nitrogen with a purity of >99.99% at a flow rate of 35 mL / min, increase the temperature to 500°C at a temperature increasing rate of 5°C / min, and reduce it with hydrogen at this temperature for 4 h, after reduction, cool it to room temperature under the protection of nitrogen, to obtain 0.77 g of Ru-Co / Fe-TiO2 benzene ring selective hydrogenation catalyst.

[0143] The Ru-Co / Fe-TiO2 benzene ring selective hydrogenation catalyst obtained in step 3) is detected, the mass of the active component is 4.82% of the carrier, the mass ratio of cobalt to ruthenium is 1:1.62, and the mass of Fe on the carrier is 5.13% of the carrier.

[0144] Preparation Example 3

[0145] 1) Mix 7 g of iron nitrate with 36 g of tetrabutyl titanate n-butanol solution, and stir at a rotation speed of 500 rpm for 5 h, separate the solution, dry the obtained solid at 90°C for 15 h, then calcine the dried solid at 350°C for 3 h, to obtain 5.2 g of Fe-TiO2.

[0146] The preparation method of the tetrabutyl titanate n-butanol solution is as follows: mix 33.5 g of tetrabutyl titanate and 2.5 g of n-butanol, to obtain 36 g of tetrabutyl titanate n-butanol solution.

[0147] 2) Take 1 g of Fe-TiO2 body obtained in step 1) and place it in a round bottom flask, add 10 mL of ruthenium trichloride n-propanol solution, while stirring at 45℃ for 4 h, add 0.13 g of cobalt nitrate hexahydrate, after stirring, age at 50℃ for 13 h, after aging, obtain a mixed solution, centrifuge, extract and separate the obtained mixed solution, then wash it with 15 mL of deionized water and 15 mL of anhydrous ethanol for 2 times respectively, finally, place the solution in a vacuum drying oven, vacuum dry at 110℃ for 10 h, and grind the obtained solid after drying into powder, to obtain 0.91 g of powdery solid.

[0148] The preparation method of the ruthenium trichloride n-propanol solution is as follows: add 1 g of anhydrous ruthenium trichloride and 50 mL of n-propanol in a beaker, ultrasonic oscillation for 50 min, then transfer the solution to a 100 mL volumetric flask, invert the volumetric flask up and down for 5 times, then stand for 3 h, and then dilute to 100 mL with n-propanol to obtain the ruthenium trichloride n-propanol solution.

[0149] 3) Calcine the 0.91 g of powdery solid obtained in step 2) at 400℃ for 5 h, after calcination, place the powdery solid in a quartz boat, and place it in a vacuum tube furnace, pass pure nitrogen with a purity of >99.99% at a flow rate of 35 mL / min, increase the temperature to 500℃ at a temperature increasing rate of 5℃ / min, and reduce it with hydrogen at this temperature for 4 h, after reduction, cool it to room temperature under the protection of nitrogen, to obtain 0.72 g of Ru-Co / Fe-TiO2 benzene ring selective hydrogenation catalyst.

[0150] The Ru-Co / Fe-TiO2 benzene ring selective hydrogenation catalyst obtained in step 3) is detected, the mass of the active component is 5.11% of the carrier, the mass ratio of cobalt to ruthenium is 1:1.69, and the mass of Fe on the carrier is 5.20% of the carrier.

[0151] Using the same method as in Preparation Example 1, adjust the amount of iron nitrate added in step 1) or the amount of ruthenium trichloride n-propanol solution and cobalt nitrate hexahydrate added in step 2), and perform parallel experiments, to obtain catalysts with different amounts of iron modification, different loadings of active components, and different proportions of active components.

[0152]

[0153]

[0154] Preparation Example 22

[0155] Example 1 was repeated except that the ruthenium-containing compound added in the preparation of the ruthenium trichloride n-propanol solution was ruthenium nitrosyl nitrate and the amount added was 1.53 g. The mass of the active component and the mass ratio of cobalt to ruthenium in the Ru-Co / Fe-TiO2 selective hydrogenation catalyst obtained in step 3) were 1:1.72 and the mass of the active component was 5.01% of the support.

[0156] Example 23

[0157] Example 1 was repeated except that the ruthenium-containing compound added in the preparation of the ruthenium trichloride n-propanol solution was ruthenium nitrosyl nitrate and the amount added was 1.53 g. The mass of the active component and the mass ratio of cobalt to ruthenium in the Ru-Co / Fe-TiO2 selective hydrogenation catalyst obtained in step 3) were 1:1.72 and the mass of the active component was 5.01% of the support.

[0158] Example 24

[0159] Example 1 was repeated except that no cobalt nitrate hexahydrate was added in step 2) and the amount of ruthenium trichloride added was 15 mL. The mass of ruthenium in the Ru / Fe-TiO2 selective hydrogenation catalyst obtained in step 3) was 5.00% of the support.

[0160] Example 25

[0161] Example 1 was repeated except that no ruthenium trichloride n-propanol solution was added in step 2) and the amount of cobalt nitrate hexahydrate added was 0.26 g. The mass of cobalt in the Co / Fe-TiO2 selective hydrogenation catalyst obtained in step 3) was 4.97% of the support.

[0162] Example 26

[0163] Example 1 was repeated except that the iron nitrate was replaced by silver nitrate and the amount of silver nitrate added was 5.6 g. The mass of silver in the Ru-Co / Ag-TiO2 selective hydrogenation catalyst obtained in step 3) was 5.03% of the mass of the support.

[0164] Example 27

[0165] Example 1 was repeated except that the iron nitrate was replaced by copper nitrate and the amount of copper nitrate added was 6.2 g. The mass of copper in the Ru-Co / Cu-TiO2 selective hydrogenation catalyst obtained in step 3) was 5.01% of the mass of the support.

[0166] Comparative Example 1

[0167] 1) Mix 11.1 g of platinum chloride with 40 g of tetrabutyl titanate n-butanol solution, and stir at a rotation speed of 500 rpm for 5 h, separate the solution, dry the obtained solid at 90 °C for 15 h, and then calcine the dried solid at 350 °C for 3 h to obtain 5.96 g of Fe-TiO2.

[0168] The tetrabutyl titanate n-butanol solution is prepared by mixing 37.2 g of tetrabutyl titanate and 2.8 g of n-butanol to obtain 40 g of tetrabutyl titanate n-butanol solution.

[0169] 2) Put 1 g of the Fe-TiO2 obtained in step 1) into a round-bottom flask, add 8 mL of ruthenium trichloride n-propanol solution, and stir at 45 °C for 4 h while adding 0.11 g of cobalt nitrate hexahydrate, and then age at 45 °C for 12 h after the stirring is completed, and obtain a mixed solution after the aging is completed, separate the mixed solution by centrifugation and extraction, and then wash the obtained mixed solution with 10 mL of deionized water and 10 mL of anhydrous ethanol for 3 times, respectively, and finally place the solution in a vacuum drying oven, and vacuum dry at 110 °C for 10 h, and then grind the obtained dried solid into a powder to obtain 0.92 g of a powdery solid.

[0170] The ruthenium trichloride n-propanol solution is prepared by adding 1 g of anhydrous ruthenium trichloride and 50 mL of n-propanol into a beaker, and then ultrasonic oscillation for 50 min, and then transfer the solution into a 100 mL volumetric flask, and then invert the volumetric flask up and down for 5 times, and then stand still for 3 h, and then dilute to 100 mL with n-propanol to obtain the ruthenium trichloride n-propanol solution.

[0171] 3) Calcine the 0.92 g of the powdery solid obtained in step 2) at 400 °C for 5 h, and then place the calcined powdery solid into a quartz boat, and then place the quartz boat into a vacuum tube furnace, and then pass pure nitrogen with a purity of > 99.99% at a flow rate of 35 mL / min, and then increase the temperature to 500 °C at a temperature increasing rate of 5 °C / min, and then reduce the powdery solid with hydrogen at the temperature for 4 h, and then cool the powdery solid to room temperature under the protection of nitrogen to obtain 0.71 g of Ru-Co / Pt-TiO2 hydrogenation catalyst.

[0172] The Ru-Co / Pt-TiO2 hydrogenation catalyst obtained in step 3) is detected, and the mass of the active component is 5.00% of the mass of the carrier, and the mass ratio of cobalt to ruthenium is 1:1.71, and the mass of Pt on the carrier is 5.02% of the mass of the carrier.

[0173] Comparative Example 2

[0174] Repeat the comparative example 1, except that the platinum chloride is replaced by magnesium nitrate, and the amount of the magnesium nitrate added is 4.9 g, and the mass of magnesium in the catalyst obtained in step 3) is 4.98% of the mass of the carrier.

[0175] Comparative Example 3

[0176] Example 1 was repeated except that the platinum chloride was replaced by molybdenum nitrate pentahydrate, and the amount of anhydrous molybdenum nitrate added was 10.5 g, and the mass of molybdenum in the catalyst obtained in step 3) was 5.04% of the mass of the carrier.

[0177] Comparative Example 4

[0178] Example 1 was repeated except that no platinum chloride was added in step 1).

[0179] Comparative Example 5

[0180] 1) 8 g of iron nitrate, 0.15 g of ammonium fluoride and 40 g of tetrabutyl titanate n-butanol solution were mixed and stirred at a speed of 500 rpm for 5 h, the solution was separated, the obtained solid was dried at 90°C for 15 h, and then the dried solid was calcined at 350°C for 3 h to obtain 6.08 g of Fe-F-TiO2.

[0181] The preparation method of the tetrabutyl titanate n-butanol solution was as follows: 37.2 g of tetrabutyl titanate and 2.8 g of n-butanol were mixed to obtain 40 g of tetrabutyl titanate n-butanol solution.

[0182] 2) 1 g of Fe-F-TiO2 obtained in step 1) was placed in a round-bottom flask, 8 mL of ruthenium trichloride n-propyl alcohol solution was added, 0.11 g of cobalt nitrate hexahydrate was added while stirring at 45°C for 4 h, and then the mixture was aged at 45°C for 12 h after completion of stirring. The obtained mixed solution was centrifuged, extracted and separated, and then washed with 10 mL of deionized water and 10 mL of anhydrous ethanol for 3 times, respectively. Finally, the solution was placed in a vacuum drying oven and dried at 110°C for 10 h, and the obtained solid after drying was ground into powder to obtain 0.88 g of powder.

[0183] The preparation method of the ruthenium trichloride n-propyl alcohol solution was as follows: 1 g of anhydrous ruthenium trichloride and 50 mL of n-propyl alcohol were added in a beaker, and the solution was transferred to a 100 mL volumetric flask after ultrasonic oscillation for 50 min. The volumetric flask was inverted up and down for 5 times and then stood for 3 h, and then the volume was adjusted to 100 mL with n-propyl alcohol to obtain the ruthenium trichloride n-propyl alcohol solution.

[0184] 3) The 0.88 g of powder obtained in step 2) was calcined at 400°C for 5 h, and then the powder was placed in a quartz boat and put into a vacuum tube furnace. High-purity nitrogen with a purity of >99.99% was introduced at a flow rate of 35 mL / min, the temperature was raised to 500°C at a rate of 5°C / min, and then the powder was reduced with hydrogen for 4 h at the temperature. After the reduction was completed, the powder was cooled to room temperature under the protection of nitrogen to obtain 0.79 g of Ru-Co / Fe-F-TiO2 hydrogenation catalyst.

[0185] The Ru-Co / Fe-F-TiO2 hydrogenation catalyst obtained in the detection step 3) has 5.04% of the active component by mass of the carrier, the mass ratio of cobalt to ruthenium is 1:1.68, the mass of Fe on the carrier is 4.99% of the mass of the carrier, and the mass of fluorine is 1.04% of the mass of the carrier.

[0186] Comparative Example 6

[0187] 1 g of activated carbon was placed in a round-bottom flask, 8 mL of an aqueous ruthenium trichloride solution was added, 0.11 g of cobalt nitrate hexahydrate was added while stirring at 45°C for 4 h, after stirring was completed, aging was performed at 45°C for 12 h, after aging was completed, a mixed solution was obtained, the pH of the mixed solution was adjusted to 9.0 with an alkaline potassium hydroxide solution, stirring was performed for 3 h, filtration was performed, the filter cake was washed with 10 mL of deionized water and 10 mL of anhydrous ethanol three times, respectively, the filter cake was slurried with water, the pH was adjusted to 14 with potassium hydroxide, reduction was performed by adding a hydrated trap solution, washing was performed, and the filter cake was placed in a vacuum drying oven, vacuum drying was performed at 110°C for 5 h, thereby obtaining 0.53 g of a Ru-Co activated carbon catalyst.

[0188] The preparation method of the aqueous ruthenium trichloride solution is as follows: 1 g of anhydrous ruthenium trichloride and 50 mL of water were added to a beaker, ultrasonic oscillation was performed for 50 min, the solution was then transferred to a 100 mL volumetric flask, the volumetric flask was inverted up and down five times, and then left to stand for 3 h, water was added to make the volume 100 mL, thereby obtaining the aqueous ruthenium trichloride solution.

[0189] The obtained Ru-Co activated carbon catalyst has 5.01% of the active component by mass of the carrier, and the mass ratio of cobalt to ruthenium is 1:1.66.

[0190] Comparative Example 7

[0191] 1) 8 g of iron nitrate was mixed with 40 g of tetrabutyl titanate n-butanol solution, and stirring was performed at a rotation speed of 500 rpm for 5 h, the solution was separated, the obtained solid was dried at 90°C for 15 h, and then the dried solid was calcined at 350°C for 3 h, thereby obtaining 6.04 g of Fe-TiO2.

[0192] The preparation method of the tetrabutyl titanate n-butanol solution is as follows: 37.2 g of tetrabutyl titanate and 2.8 g of n-butanol were mixed, thereby obtaining 40 g of tetrabutyl titanate n-butanol solution.

[0193] 2) Take 1 g of Fe-TiO2 body obtained in step 1) and place it in a round bottom flask, add 8 mL of ruthenium trichloride n-propanol solution, add 0.1 g of rhodium trichloride hydrate while stirring at 45℃ for 4 h, after stirring, age at 45℃ for 12 h, after aging, obtain a mixed solution, separate the obtained mixed solution by centrifugation and extraction, then wash it with 10 mL of deionized water and 10 mL of anhydrous ethanol for 3 times respectively, finally, place the solution in a vacuum drying oven, vacuum dry at 110℃ for 10 h, and grind the obtained solid after drying into powder to obtain 0.87 g of powdery solid.

[0194] The preparation method of the ruthenium trichloride n-propanol solution is as follows: add 1 g of anhydrous ruthenium trichloride and 50 mL of n-propanol in a beaker, ultrasonic oscillation for 50 min, then transfer the solution to a 100 mL volumetric flask, invert the volumetric flask up and down for 5 times, then stand for 3 h, and then dilute to 100 mL with n-propanol to obtain the ruthenium trichloride n-propanol solution.

[0195] 3) Calcine 0.87 g of powdery solid obtained in step 2) at 400℃ for 5 h, after calcination, place the powdery solid in a quartz boat and put it into a vacuum tube furnace, pass pure nitrogen with a purity of >99.99% at a flow rate of 35 mL / min, increase the temperature to 500℃ at a rate of 5℃ / min, and reduce it with hydrogen at this temperature for 4 h, after reduction, cool it to room temperature under the protection of nitrogen to obtain 0.69 g of Ru-Rh / Fe-TiO2 hydrogenation catalyst.

[0196] The Ru-Rh / Fe-TiO2 hydrogenation catalyst obtained in step 3) is detected, the mass of active components is 5.02% of the carrier, the mass ratio of rhodium to ruthenium is 1:1.68, and the mass of Fe on the carrier is 5.00% of the carrier.

[0197] Comparative Example 8

[0198] Repeat Comparative Example 7, except that the rhodium trichloride hydrate in step 2) is replaced by platinum chloride, and the addition amount of platinum chloride is 0.13 g, and the mass of active components in the catalyst obtained in step 3) is 4.97%, and the mass ratio of platinum to ruthenium is 1:1.71.

[0199] Comparative Example 9

[0200] 1) Mix 8 g of iron nitrate with 40 g of tetrabutyl titanate n-butanol solution and stir at a speed of 500 rpm for 5 h, separate the solution, dry the obtained solid at 90℃ for 15 h, then calcine the dried solid at 350℃ for 3 h to obtain 5.97 g of Fe-TiO2.

[0201] The preparation method of the tetrabutyl titanate n-butanol solution is as follows: mix 37.2 g of tetrabutyl titanate and 2.8 g of n-butanol to obtain 40 g of tetrabutyl titanate n-butanol solution.

[0202] 2) Put 1 g of Fe-TiO2 body obtained in step 1) into a round bottom flask, add 8 mL of aqueous solution of platinum chloride, add 0.11 g of cobalt nitrate hexahydrate while stirring at 45°C for 4 h, after completion of stirring, age at 45°C for 12 h, after completion of aging, obtain a mixed solution, separate the obtained mixed solution by centrifugation and extraction, then wash with 10 mL of deionized water and 10 mL of anhydrous ethanol for 3 times respectively, finally, put the solution into a vacuum drying oven, vacuum dry at 110°C for 10 h, and grind the obtained solid after drying into powder to obtain 0.88 g of powdery solid.

[0203] The preparation method of the aqueous solution of platinum chloride is as follows: add 1.6 g of platinum chloride and 50 mL of water into a beaker, ultrasonically shake for 50 min, then transfer the solution to a 100 mL volumetric flask, invert the volumetric flask up and down for 5 times, then stand for 3 h, and dilute to 100 mL with water to obtain the aqueous solution of platinum chloride.

[0204] 3) Calcine 0.88 g of the powdery solid obtained in step 2) at 400°C for 5 h, after completion of calcination, put the powdery solid into a quartz boat, put into a vacuum tube furnace, pass pure nitrogen with a purity of >99.99% at a flow rate of 35 mL / min, increase the temperature to 500°C at a temperature increasing rate of 5°C / min, and reduce with hydrogen at the temperature for 4 h, after completion of reduction, cool to room temperature under the protection of nitrogen to obtain 0.67 g of Pt-Co / Fe-TiO2 hydrogenation catalyst.

[0205] The Pt-Co / Fe-TiO2 hydrogenation catalyst obtained in step 3) is detected, the mass of active component is 5.04% of the carrier, the mass ratio of cobalt to platinum is 1:1.69, and the mass of Fe on the carrier is 5.01% of the carrier.

[0206] Comparative Example 10

[0207] Repeat Comparative Example 9, except that the aqueous solution of platinum chloride in step 2) is replaced by an aqueous solution of ammonium metatungstate, the amount of the aqueous solution of ammonium metatungstate added is 8 mL, and the concentration of the aqueous solution of ammonium metatungstate is 12 g / L, in the catalyst obtained in step 3), the mass of active component is 5.00%, and the mass ratio of cobalt to tungsten is 1:1.73.

[0208] The catalysts obtained in Preparation Examples 1-27 and Comparative Examples 1-10 are used for the preparation of HMDA, and the method is as follows:

[0209] A) Into a high-pressure reactor, 0.1 g of the prepared catalyst, 15 mL of tetrahydrofuran and 1 g of 4,4-diaminodiphenylmethane were added, a magnetic bar was put in and the reactor was sealed, then the air in the reactor was replaced with nitrogen for 4 times, the reactor was vacuumized, heating was started, when the temperature reached 100℃, hydrogen was introduced and the pressure was increased to 2 MPa, the reaction was carried out at a stirring speed of 500 rpm for 3 h, after the reaction was completed, filtration was carried out, and 4,4-diaminodicyclohexylmethane was obtained.

[0210] The catalysts obtained in Preparation Examples 1-27 and Comparative Examples 1-10 were respectively detected for the preparation of HMDA, the yield of the product was obtained, and the content of HMDA in the product was further calculated, and the selectivity of HMDA was calculated, and the results are shown in Table 1.

[0211] Table 1

[0212]

[0213]

[0214] According to the application of the catalysts prepared in Preparation Examples 1-27 and Comparative Examples 1-10 in the reaction, it can be inferred that the selective hydrogenation catalyst for benzene ring provided by the present application has good catalytic performance by using doped titanium dioxide to load ruthenium-cobalt, and compared with catalysts using other carriers or active components, the selectivity of the required 4,4-diaminodicyclohexylmethane is higher, and the catalyst has high practicability.

Claims

1. A method for applying a selective hydrogenation catalyst for benzene rings, characterized in that: The method includes the following steps: A) Adding a benzene ring selective hydrogenation catalyst, solvent II and 4,4-diaminodiphenylmethane to a reaction vessel, passing hydrogen gas through the reaction vessel under air-isolated conditions and heating and pressurizing, stirring the reaction, filtering the mixture after the reaction is completed to obtain 4,4-diaminodicyclohexylmethane; In step A), solvent II is one of tetrahydrofuran, 1,4-dioxane, and dimethyl sulfoxide; the heating temperature is 60-140°C; the pressurization pressure is 1-3 MPa; the stirring reaction time is 1-5 h; the stirring reaction speed is 200-800 rpm; and the amount of catalyst added is 2-25% of the mass of 4,4-diaminodiphenylmethane. The catalyst includes a support and an active component loaded on the surface of the support; wherein the support is a titanium dioxide support modified by one or more elements selected from iron, silver, and copper; the active component is ruthenium and cobalt; the mass of the active component is 0.5% to 15% of the support; and the mass of the modifying element on the support is 0.5% to 10% of the support.

2. The application method according to claim 1, characterized in that: The carrier is an iron-modified titanium dioxide carrier.

3. The application method according to claim 1, characterized in that: The active component is 3% to 7% of the carrier by mass; and / or The mass of the modifying element on the carrier is 2% to 7% of the carrier; and / or The mass ratio of cobalt to ruthenium in the active component is 1:1~2.

4. The application method according to claim 3, characterized in that: The mass ratio of cobalt to ruthenium in the active component is 1:1.5~1.

8.

5. The application method according to any one of claims 1-4, characterized in that: The preparation of the catalyst includes the following steps: 1) Mix the precursor of the modified element with the titanium precursor, stir and separate, and dry and calcine the resulting solid to obtain the modified titanium dioxide support. 2) Place the modified titanium dioxide support obtained in step 1) into a reaction vessel, add a solution containing ruthenium precursor, stir and add cobalt precursor, after aging, centrifuge, extract and separate, wash, dry and grind to obtain powdered solid; 3) After calcining the powdered solid obtained in step 2), it is reduced with a reducing gas under oxygen-free conditions. After the reduction is completed, it is cooled to room temperature to obtain a benzene ring selective hydrogenation catalyst.

6. The application method according to claim 5, characterized in that: Step 1) The precursor of the modified element is a precursor of any one of the elements selected from iron, silver, and copper; and / or The titanium precursor mentioned in step 1) is a tetrabutyl titanate n-butanol solution; and / or In step 1), the mass ratio of the precursor of the modified element to the tetrabutyl titanate n-butanol solution is 1:3~8; and / or Step 1) The stirring speed is 300~1000 rpm; and / or The stirring time in step 1) is 1~10 hours; and / or The drying temperature in step 1) is 60~120℃; and / or The drying time in step 1) is 8-24 hours; and / or Step 1) The calcination temperature is 250~450℃; and / or Step 1) The calcination time is 1-6 hours; and / or The cobalt precursor mentioned in step 2) is cobalt nitrate hexahydrate; and / or The ruthenium precursor mentioned in step 2) is a ruthenium trichloride n-propanol solution; and / or Step 2) The solid-liquid ratio of the modified titanium dioxide support to the solution containing the ruthenium precursor is 1:3~15; and / or Step 2) The mass ratio of the cobalt precursor to the ruthenium precursor is 1:0.42~0.83; and / or The stirring temperature in step 2) is 25~65℃; and / or The stirring time in step 2) is 2-6 hours; and / or Step 2) The aging time is 6-20 hours; and / or Step 2) The extraction reagent used is deionized water or anhydrous ethanol; and / or Step 3) The roasting temperature is 300~500℃; and / or Step 3) The roasting time is 2-8 hours; and / or Step 3) The reducing gas is hydrogen; and / or Step 3) The reduction temperature is 200~600℃; and / or Step 3) The reduction time is 2-6 hours; and / or The heating rate for the reduction in step 3) is 4~8℃ / min.

7. The application method according to claim 6, characterized in that: The precursor of the modified element in step 1) is ferric nitrate; and / or The preparation method of the tetrabutyl titanate-n-butanol solution is as follows: tetrabutyl titanate and n-butanol are mixed at a mass ratio of 10:0.5~1 and stirred for 1~6 hours to obtain the tetrabutyl titanate-n-butanol solution. and / or In step 1), the mass ratio of the precursor of the modified element to the tetrabutyl titanate n-butanol solution is 1:4~6; and / or Step 1) The stirring speed is 400~800 rpm; and / or The stirring time in step 1) is 2-8 hours; and / or The drying temperature in step 1) is 70~110℃; and / or The drying time in step 1) is 12-20 hours; and / or Step 1) The calcination temperature is 300~400℃; and / or Step 1) The calcination time is 2-5 hours; and / or Step 2) The solid-liquid ratio of the modified titanium dioxide support to the solution containing the ruthenium precursor is 1:5~12; and / or Step 2) The mass ratio of the cobalt precursor to the ruthenium precursor is 1:0.63~0.75; and / or The stirring temperature in step 2) is 35~55℃; and / or The stirring time in step 2) is 3-5 hours; and / or Step 2) The aging time is 10-16 hours; and / or Step 3) The roasting temperature is 350~450℃; and / or Step 3) The roasting time is 4-6 hours; and / or Step 3) The reduction temperature is 400~550℃; and / or Step 3) The reduction time is 3-5 hours; and / or The heating rate for the reduction in step 3) is 4~6℃ / min.

8. The application method according to claim 5, characterized in that: The method for preparing the solution containing the ruthenium precursor in step 2) is as follows: dissolve the ruthenium-containing compound in solvent I, sonicate and let stand to obtain the solution containing the ruthenium precursor.

9. The application method according to claim 8, characterized in that: The ruthenium-containing compound is one or more of anhydrous ruthenium trichloride, nitrosyl ruthenium nitrate, and ruthenium acetate; and / or Solvent I is n-propanol; and / or The solid-liquid ratio of the ruthenium-containing compound to solvent I is 5-20 g / L; and / or The duration of the ultrasonic oscillation is 30-60 minutes; and / or The settling time is 2-5 hours.

10. The application method according to claim 9, characterized in that: The ruthenium-containing compound is anhydrous ruthenium trichloride; and / or The solid-liquid ratio of the ruthenium-containing compound to solvent I is 7-15 g / L; and / or The duration of the ultrasonic oscillation is 40-55 minutes; and / or The settling time is 3-4 hours.

11. The application method according to claim 1, characterized in that: Solvent II mentioned in step A) is tetrahydrofuran; and / or The heating temperature described in step A) is 80~120℃; and / or The pressure applied in step A) is 1.5~2.5 MPa; and / or The stirring reaction time described in step A) is 2-4 hours; and / or The stirring speed in step A) is 300~700 rpm; and / or The amount of catalyst added in step A) is 6 to 15% of the mass of 4,4-diaminodiphenylmethane.

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