Catalyst, preparation method thereof and application of catalyst in cyclohexene preparation

Abstract

The invention discloses a catalyst, a preparation method thereof and application of the catalyst in cyclohexene preparation. The catalyst takes porous polyamide as a carrier, takes ruthenium metal as a main active component, and comprises one or more auxiliary components selected from boron, zinc, aluminum, iron, molybdenum, platinum, nickel, lanthanum, cerium, copper and cobalt. The method comprises the following steps: mixing a diamine monomer and a pore-foaming agent, dissolving in an organic solvent, then adding into a binary acyl chloride solution dissolved in the organic solvent, and carrying out polymerization reaction to form polyamide; removing the pore-foaming agent by using a non-solvent, washing with water, and drying to obtain a porous polyamide carrier; the preparation method comprises the following steps: putting a porous polyamide carrier, a main active component ruthenium metal salt and an auxiliary compound into water, stirring at room temperature, and slowly heating to remove water, so as to obtain a solid; heating and reducing the solid in a hydrogen atmosphere; and washing, drying and roasting in an inert atmosphere. The catalyst is used for preparing cyclohexene through partial hydrogenation of benzene and has high activity, high selectivity and good stability.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of fine chemical industry, in particular to a catalyst for partial hydrogenation of benzene to cyclohexene, a preparation method thereof and an application thereof in catalyzing partial hydrogenation of benzene to prepare cyclohexene. BACKGROUND

[0002] The partial hydrogenation of benzene reaction is a very important organic synthesis process in the field of chemical industry, which is mainly used for producing high value-added products such as cyclohexene. As an important chemical intermediate, cyclohexene has been widely used in the fields of synthetic fibers, plastics, rubbers, medicines and spices. Traditional partial hydrogenation catalysts of benzene are mostly based on metal catalysts such as nickel, platinum and palladium. These catalysts have problems such as low selectivity, insufficient activity and easy poisoning. In recent years, noble metal catalysts such as ruthenium have attracted widespread attention due to their excellent catalytic performance, but their high cost has greatly limited their large-scale application.

[0003] The selection of catalyst carrier plays a crucial role in the performance of the catalyst. Traditional catalyst carriers mainly include inorganic materials such as silica gel, alumina, zirconia and activated carbon. Although these materials have certain specific surface area and void structure, they still have problems such as low activity due to insufficient dispersion, poor stability leading to easy deactivation of the catalyst, and weak interaction between the carrier and the active component, leading to easy loss of the active component. In recent years, organic polymer carriers have gradually attracted more and more attention due to their unique pore structure, high specific surface area and good chemical stability.

[0004] In order to reduce the cost of the catalyst, overcome the problems of low activity, poor stability and easy loss of the active component of the existing partial hydrogenation catalyst of benzene, it is necessary to provide a partial hydrogenation catalyst of benzene which is simple and easy to prepare, has high catalytic activity, high stability, strong interaction between the catalyst carrier and the active component, and reduces the loss of the active component of the catalyst, as well as a preparation method and application thereof. SUMMARY

[0005] The present application uses porous polyamide as a catalyst carrier, ruthenium as a main catalyst, and additives, and realizes high selectivity, high activity and high stability of the partial hydrogenation of benzene to cyclohexene by optimizing the preparation process and composition of the catalyst, thereby solving the problems of low activity, low selectivity, large amount of use and poor stability of the existing catalyst.

[0006] According to one aspect of the present application, a partial hydrogenation catalyst of benzene is provided, wherein the catalyst uses porous polyamide as a carrier, ruthenium metal as a main active component, and one or more additive components selected from boron, zinc, aluminum, iron, molybdenum, platinum, nickel, lanthanum, cerium, copper and cobalt.

[0007] According to the present application, in some embodiments, the mass ratio of ruthenium to the porous polyamide support in the catalyst is 1%-50%, preferably 15%.

[0008] According to the present application, in some embodiments, the promoter component is selected from boron, zinc, cerium.

[0009] According to the present application, in some embodiments, the mass ratio of ruthenium, boron, zinc and cerium in the catalyst is 1:0.1-20:0.1-50:0.1-20, preferably 1:0.5:25:5.

[0010] According to the present application, in some embodiments, the porous polyamide has a BET specific surface area of 25-35 m 2 / g, an average pore size of 25-35 nm, and a total pore volume of 0.15-0.25 cm 3 / g according to nitrogen adsorption-desorption test.

[0011] According to the present application, in some embodiments, the particle size D50 of the catalyst is 15-25 μm.

[0012] According to another aspect of the present application, there is provided a method for preparing a catalyst for partial hydrogenation of benzene, the method comprising:

[0013] S1, preparation of a porous polyamide support

[0014] After mixing the diamine monomer and the porogen, the mixture is dissolved in an organic solvent, and then a solution of diacyl chloride dissolved in an organic solvent is added for mixing, so that the reaction solution undergoes a polymerization reaction to form a polyamide; subsequently, the porogen is removed by a non-solvent, and the porous polyamide support is obtained after water washing and drying.

[0015] S2, preparation of a catalyst

[0016] The porous polyamide support prepared in S1 is placed in water together with a main active component, i.e. a ruthenium metal salt, and a promoter compound (e.g. a salt), and then stirred at room temperature, followed by slow heating to remove water to obtain a solid; the solid is heated and reduced in a hydrogen atmosphere; and the catalyst is obtained after water washing, drying and calcination in an inert atmosphere.

[0017] According to the present application, in some embodiments, in S1, the diacyl chloride is prepared by the following step S0:

[0018] S0, a diacid is dissolved in an organic solvent, and then an acyl halide reagent is added at room temperature; after the addition of the acyl halide reagent is completed, the reaction solution is heated to start the reaction until the reaction is complete, to obtain a diacyl chloride solution.

[0019] According to the present application, in some embodiments, in S0, the acyl halide reagent is one or more selected from the group consisting of sulfurous chloride, phosphorus trichloride, phosphorus pentachloride, oxalyl chloride, carbon tetrachloride, phosphorus tribromide, preferably oxalyl chloride; in specific embodiments, the acyl halide reagent can be used in a solvent, for example, oxalyl chloride is used in the above organic solvents.

[0020] According to the present application, in some embodiments, in S0, the diacid is selected from aliphatic diacid or aromatic diacid, in particular, the aliphatic diacid is one or more selected from the group consisting of oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, maleic acid and fumaric acid; the aromatic diacid is one or more selected from the group consisting of phthalic acid, isophthalic acid, terephthalic acid, 2,6-naphthalene dicarboxylic acid and 4,4'-biphenyl dicarboxylic acid; more particularly, the aliphatic diacid is selected from adipic acid, and the aromatic diamine is selected from terephthalic acid.

[0021] According to the present application, in some embodiments, in S0, the molar ratio of diacid to acyl halide reagent is 1:0.5-1:10, preferably 1:2-1:4.

[0022] According to the present application, in some embodiments, in S0, the reaction heating temperature is 30-60°C, preferably 40-50°C, more preferably 45°C.

[0023] According to the present application, in some embodiments, in S0, the reaction time is 0.5-12h, preferably 3-5h.

[0024] According to the present application, in some embodiments, each organic solvent is independently one or more selected from the group consisting of toluene, xylene, dichloromethane, trichloromethane, acetone, cyclohexanone, N,N-dimethylformamide, N,N-dimethylacetamide, dioxane and tetrahydrofuran, preferably N,N-dimethylformamide.

[0025] According to the present application, in some embodiments, in S1, the diamine monomer is selected from aliphatic diamine or aromatic diamine, in particular, the aliphatic diamine is one or more selected from the group consisting of ethylenediamine, butanediamine, pentanediamine, hexanediamine, diaminopropane; the aromatic diamine is one or more selected from the group consisting of diphenylethylenediamine, xylylenediamine, o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 4,4'-diaminobiphenyl, 1,8-diaminonaphthalene; more particularly, the aliphatic diamine is selected from hexanediamine, and the aromatic diamine is selected from p-phenylenediamine.

[0026] Preferably, the diamine monomer and the above-mentioned reaction-prepared diacyl chloride monomer are reacted in an organic solvent selected from the group consisting of N,N-dimethylformamide, N,N-dimethylacetamide, tetrahydrofuran and N-methylpyrrolidone, preferably N,N-dimethylformamide.

[0027] According to the present application, in some embodiments, the molar ratio of the diamine monomer in S1 to the diacid used to prepare the diacyl chloride in S0 is 1:0.1-1:10, preferably 1:1.

[0028] According to the present application, in some embodiments, in S1, the porogen is one or more selected from polyethylene glycol (PEG, molecular weight 400-6000), polyvinylpyrrolidone, lithium chloride, calcium chloride, preferably PEG-1000.

[0029] According to the present application, in some embodiments, in S1, the porogen accounts for 5%-40% of the mass of the diamine, preferably 10%.

[0030] According to the present application, in some embodiments, in S1, the diamine is first mixed uniformly with the porogen in an organic solvent, and then slowly mixed with the prepared diacyl chloride solution at -10°C-10°C, preferably 0°C-5°C.

[0031] According to the present application, in some embodiments, in S1, the polymerization temperature is 40°C-100°C, preferably 70°C.

[0032] According to the present application, in some embodiments, in S1, the polymerization time is 1h-12h, preferably 6h.

[0033] According to the present application, in some embodiments, in S1, after the polymerization is completed, the polymerization solution is cast into a film, and then immersed in a non-solvent bath to completely exchange the solvent and the porogen with the non-solvent, forming a porous structure.

[0034] According to the present application, in some embodiments, in S1, the porous polyamide is obtained by washing 3-5 times with water and freeze-drying.

[0035] According to the present application, in some embodiments, in S1, the non-solvent is selected from water / ethanol mixture, water / methanol mixture, water / ethylene glycol mixture, and water / acetic acid mixture, preferably water / ethanol mixture.

[0036] According to the present application, in some embodiments, in S1, the volume ratio of water to ethanol in the water / ethanol mixture is 1:0.1-1:10, preferably 1:1.

[0037] According to the present application, in some embodiments, in S1, the immersion time in the non-solvent bath, such as water / ethanol mixture, is 10h-72h, preferably 48h.

[0038] According to the present application, in some embodiments, in S1, the freeze-drying temperature is -100°C--20°C, preferably -50°C.

[0039] According to the present application, in some embodiments, in S1, the freeze-drying time is 12-48h, preferably 24h.

[0040] According to the present application, in some embodiments, in S2, the ruthenium metal salt is one or two selected from the group consisting of ruthenium trichloride trihydrate, ruthenium nitrate, ruthenium acetate, potassium hexachlororuthenate, potassium hexacyanoruthenate, potassium ruthenate, ruthenium tribromide, ruthenium nitrosyl nitrate and ruthenium acetylacetonate, preferably ruthenium trichloride trihydrate.

[0041] According to the present application, in some embodiments, in S2, the mass ratio of ruthenium in the above-mentioned ruthenium metal salt to the carrier porous polyamide is 1%-50%, preferably 15%.

[0042] According to the present application, in some embodiments, in S2, the above-mentioned auxiliary agent is one or several selected from the group consisting of boron, zinc, aluminum, iron, molybdenum, platinum, nickel, lanthanum, cerium, copper, cobalt, preferably selected from the group consisting of boron, zinc, cerium.

[0043] According to the present application, in some embodiments, in S2, the boron in the auxiliary agent is from boric acid, borax, preferably from boric acid.

[0044] According to the present application, in some embodiments, in S2, the zinc in the auxiliary agent is from one or two of zinc sulfate heptahydrate, zinc chloride, zinc bromide, zinc iodide, zinc acetate, zinc nitrate, preferably zinc sulfate heptahydrate.

[0045] According to the present application, in some embodiments, in S2, the cerium in the auxiliary agent is from one or two of cerium trichloride, cerium sulfate, cerium nitrate, cerium acetate, cerium oxalate, preferably cerium sulfate.

[0046] According to the present application, in some embodiments, in S2, the mass ratio of the above-mentioned ruthenium, boron, zinc and cerium is 1:0.1-20:0.1-50:0.1-20, preferably 1:0.5:25:5.

[0047] According to the present application, in some embodiments, in S2, ultrasonic stirring is used, and the time of ultrasonic stirring is 5h-24h, preferably 12h.

[0048] According to the present application, in some embodiments, in S2, the heating rate is 0.1-5℃ / min, preferably 0.5℃ / min.

[0049] According to the present application, in some embodiments, in S2, the target temperature for removing water is 60℃-110℃, preferably 80℃.

[0050] According to the present application, in some embodiments, in S2, the heating temperature in the hydrogen atmosphere is 100℃-300℃, for example 150℃, 200℃, 250℃.

[0051] According to the present application, in some embodiments, in S2, the heating reduction time in hydrogen atmosphere is 5-48h, preferably 24h.

[0052] According to the present application, in some embodiments, in S2, the drying is vacuum drying, and the drying temperature is 50-100°C, preferably 80°C.

[0053] According to the present application, in some embodiments, in S2, the drying is vacuum drying, and the drying time is 5-24h, preferably 12h.

[0054] According to the present application, in some embodiments, in S2, the inert atmosphere is argon atmosphere, and the calcination temperature is 100-300°C, for example, 150°C, 200°C, 250°C.

[0055] According to the present application, in some embodiments, in S2, the inert atmosphere is argon atmosphere, and the calcination time is 1-12h, preferably 4h.

[0056] According to another aspect of the present application, the present application provides a method for preparing cyclohexene using the catalyst or the catalyst prepared by the method, which comprises the following steps:

[0057] mixing the catalyst for hydrogenation of benzene moiety described above with benzene, and reacting in hydrogen atmosphere to obtain cyclohexene.

[0058] According to the present application, in some embodiments, the catalyst for hydrogenation of benzene moiety accounts for 1-40% of the mass of benzene, preferably 15%.

[0059] According to the present application, in some embodiments, the volume ratio of the benzene and water is 1:1-1:5, preferably 1:2;

[0060] According to the present application, in some embodiments, the molar ratio of the benzene and hydrogen is 1:1-1:6, preferably 1:2.2.

[0061] According to the present application, in some embodiments, the reaction pressure is 2-6 MPa, preferably 3.75 MPa.

[0062] According to the present application, in some embodiments, the reaction temperature is 120-180°C, preferably 135°C.

[0063] According to the present application, in some embodiments, the reaction time is 10-90min, preferably 20min.

[0064] Beneficial effects

[0065] 1) The porous polyamide is used as the catalyst carrier in the present application, which improves the specific surface area of the catalyst and the dispersity of the active component, and can effectively inhibit the catalyst agglomeration, and improve the activity and selectivity of the catalyst;

[0066] 2) The porous polyamide is used as the carrier in the present application, and the amide bond on the surface of the porous polyamide can enhance the interaction between the carrier and the active component, improve the stability and service life of the catalyst, and greatly reduce the problem of active component loss;

[0067] 3) The catalyst with the porous polyamide as the carrier provided in the present application has simple preparation method, mild reaction condition, easy control, simple operation, and not only has high conversion rate for benzene, but also has high selectivity for cyclohexene, and thus is suitable for the industrial catalytic partial hydrogenation of benzene to prepare cyclohexene.

[0068] In summary, the preparation method of the benzene partial hydrogenation catalyst with the porous polyamide as the carrier provided in the present application is simple and easy to control, and the catalyst also has high activity, high selectivity and good stability, which can greatly reduce the production cost of the industrial partial hydrogenation of benzene to prepare cyclohexene, and has very important economic significance for the industrial production of cyclohexene. BRIEF DESCRIPTION OF DRAWINGS

[0069] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the drawings needed in the specific embodiments or the prior art description will be briefly introduced as follows. Obviously, the drawings in the following description are some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without creative labor.

[0070] Figures 1-4 The particle size distribution diagrams of the catalyst 1-catalyst 4 prepared in the example 1-the example 4 are shown respectively. DETAILED DESCRIPTION

[0071] The present application has been described in detail in the foregoing, but the above embodiments are only illustrative in nature and are not intended to limit the present application. In addition, this document is not limited by any theory described in the foregoing prior art or summary or the following examples.

[0072] Unless otherwise expressly stated, ranges of values included within the application file are inclusive of any sub-ranges within the range and any values within the minimum and maximum units of the given range. Unless otherwise expressly stated, values within the application file are indicated to the nearest 0.001, 0.0001, or 0.00001 of the unit in which the value is expressed, unless exact values are stated. Except in the operating and comparative examples, or where otherwise explicitly indicated, all numbers in this application file are to be understood as modified in all instances by the term "about." The use of "about" indicates that the described value allows some slight imprecision, with a suitable degree of accuracy in light of the overall proximity of the indicated value to the value it describes, in which values are understood to be close enough to the stated value that not using the term "about" would suggest a finding of inaccuracy that would otherwise not be appreciated. "About" can indicate values that are near the theoretical or theoretical "ideal" value. For example, "about" can include a range of less than 10%, less than 5%, less than 4%, less than 3%, less than 2%, less than 1%, or less than 0.5% of the stated value.

[0073] The application will be further described with reference to the following examples. It should be appreciated that these examples are provided for purposes of illustration only, and are not intended to limit the scope of the application.

[0074] Except in the operating and comparative examples, or where otherwise explicitly indicated, all materials, reagents, methods, etc. employed in the application file are of a type as customarily used by those in the field.

[0075] Hexanediamine and adipic acid are produced from Xuyang Group's own factory;

[0076] p-Phenylenediamine and terephthalic acid are purchased from Merck.

[0077] Example 1:

[0078] Step 1: Preparation of adipoyl chloride

[0079] In a 250 mL two-necked flask, 11.3 mmol of adipic acid was added, followed by 40 mL of N,N-dimethylformamide, which was completely dissolved. Then 33.9 mmol of oxalyl chloride was dissolved in 20 mL of N,N-dimethylformamide and added dropwise to the above reaction solution. The temperature of the reaction solution was then heated to 45°C, and the reaction was carried out for 4 h. No gas bubbles were precipitated in the reaction solution, and TLC detection showed that the reaction was complete. Then the heating was stopped, and the adipoyl chloride reaction solution was obtained and stored at room temperature.

[0080] Step 2: Preparation of porous polyamide carrier 1:

[0081] Weigh (1.31 g) 11.3 mmol of ethylenediamine and 0.13 g of PEG-1000 into a 250 mL two-necked flask, then measure 30 mL of solvent N,N-dimethylformamide to completely dissolve it, cool it to 0°C in an ice water bath, then take the reaction solution of adipoyl chloride prepared in step 1 with a syringe and slowly add it to the above solution, after the addition is completed, remove the ice water bath, and after warming to room temperature, heat the mixture to 70°C, and react for 6 h. After the reaction is completed, the reaction polymerization solution is cast into a film, and immersed in a mixed solution of water and ethanol (V 水 :V 乙醇 = 1:1) for 48 h to completely exchange the solvents, pore-forming agents and non-solvents, form a porous structure, and finally washed with water for 3-5 times, freeze-dried to -50°C, and dried for 24 h to obtain a porous polyamide 1 used as a catalyst carrier. According to nitrogen adsorption-desorption test, its BET specific surface area: 33.4622 m 2 / g, BJH adsorption average pore size: 26.2143 nm, total pore volume (BJH adsorption): 0.194619 cm 3 / g.

[0082] Step 3: Preparation of benzene part hydrogenation catalyst 1:

[0083] Weigh 2 g of the porous polyamide 1 prepared in step 2, 0.8 g of ruthenium trichloride trihydrate, 0.86 g of boric acid, 32.8 g of zinc sulfate heptahydrate, and 6.1 g of cerium sulfate into a 500 mL two-necked flask, then measure 150 mL of water to mix it evenly, and then stir under ultrasonic conditions for 12 h. Then slowly warm the reaction solution to 80°C at a rate of 0.5°C / min, and after the water is completely evaporated, a solid is obtained. The solid is heated to 250°C under a hydrogen atmosphere for 24 h. After washing the solid with water for 3 times, it is placed under vacuum conditions, and the temperature is increased to 80°C for drying for 12 h. Finally, the solid is placed in an argon atmosphere, heated to 200°C, and calcined for 4 h to obtain the desired target catalyst, which is recorded as catalyst 1. The particle size D50 of the catalyst 1 is 17.905 μm by laser particle size analyzer test. Figure 1 The particle size distribution diagram of catalyst 1 is shown.

[0084] Example 2:

[0085] Step 1, prepare adipoyl chloride as in example 1.

[0086] Step 2, refer to example 1 to measure the corresponding p-phenylenediamine, PEG-1000, and adipoyl chloride, and react according to the method of step 2 in example 1 to obtain a porous polyamide 2 used as a catalyst carrier; according to nitrogen adsorption-desorption test, its BET specific surface area: 30.3352 m 2 / g, BJH adsorption average pore diameter: 29.5791 nm, total pore volume (BJH adsorption) 0.215708 cm 3 / g.

[0087] Step 3, then according to the method of step 3 in example 1, porous polyamide 2, ruthenium trichloride trihydrate, boric acid, zinc sulfate heptahydrate and cerium sulfate were weighed and treated to obtain the desired target catalyst, recorded as catalyst 2, which was tested by laser particle size instrument and the particle size D50 was 21.241 μm. Figure 2 The particle size distribution diagram of catalyst 2 is shown.

[0088] Example 3:

[0089] Step 1, according to the method of step 1 in example 1, terephthalic acid, oxalyl chloride were weighed and reacted to obtain terephthaloyl chloride.

[0090] Step 2, according to the method of step 2 in example 1, hexamethylene diamine, PEG-1000, terephthaloyl chloride were weighed and reacted to obtain porous polyamide 3 which can be used as a catalyst carrier; according to nitrogen adsorption-desorption test, its BET specific surface area: 30.1415 m 2 / g, BJH adsorption average pore diameter: 31.6806 nm, total pore volume (BJH adsorption) 0.223570 cm 3 / g.

[0091] Step 3, then according to the method of step 3 in example 1, porous polyamide 3, ruthenium trichloride trihydrate, boric acid, zinc sulfate heptahydrate and cerium sulfate were weighed and treated to obtain the desired target catalyst, recorded as catalyst 3, which was tested by laser particle size instrument and the particle size D50 was 20.613 μm. Figure 3 The particle size distribution diagram of catalyst 3 is shown.

[0092] Example 4:

[0093] Step 1, terephthaloyl chloride was prepared according to example 3.

[0094] Step 2, according to the method of step 2 in example 1, p-phenylenediamine, PEG-1000, terephthaloyl chloride were weighed and reacted to obtain porous polyamide 4 which can be used as a catalyst carrier; according to nitrogen adsorption-desorption test, its BET specific surface area: 29.5314 m 2 / g, BJH adsorption average pore diameter: 31.2380 nm, total pore volume (BJH adsorption) 0.215381 cm 3 / g.

[0095] Step 3. Then, the porous polyamide 4, ruthenium trichloride trihydrate, boric acid, zinc sulfate heptahydrate and cerium sulfate were weighed and treated according to the method of Step 3 in Example 1, to obtain the desired target catalyst, which is recorded as catalyst 4. The particle size D50 of catalyst 4 was 20.924 μm as tested by a laser particle size analyzer. Figure 4 The particle size distribution diagram of catalyst 4 is shown.

[0096] Experimental Examples 1-4:

[0097] The porous polyamide supported benzene partial hydrogenation catalysts 1-4 prepared in Examples 1-4 were respectively used in the reaction of benzene partial hydrogenation to cyclohexene, and the specific reaction conditions were as follows: the reaction temperature was 135℃, the reaction pressure was 3.75 MPa, the reaction time was 20 min, the molar ratio of benzene to hydrogen was 1:2.2, the volume of water was 2 times the volume of benzene, and the mass ratio of the porous polyamide supported benzene partial hydrogenation catalyst to benzene was 15%. The specific reaction results are shown in Table 1:

[0098] Table 1: Reaction results of catalysts 1-4 in the reaction of benzene partial hydrogenation to cyclohexene

[0099]

[0100]

[0101] Experimental Examples 5-8:

[0102] The porous polyamide supported benzene partial hydrogenation catalysts 1-4 prepared in Examples 1-4 were used in the reaction of benzene partial hydrogenation to cyclohexene in a continuous hydrogenation reactor, and the reaction conditions were as follows: in a 2L reactor, the reaction temperature was 135℃, the catalyst dosage was 198g, the benzene flow rate was 75 mL / min, the water flow rate was 150 mL / min, the molar ratio of benzene to hydrogen was 1:2.2, the residence time of benzene in the reactor was 20 min, and the continuous reaction time was 100 h. The specific reaction results are shown in Table 2:

[0103] Table 2: Reaction results of catalysts 1-4 in the reaction of benzene partial hydrogenation to cyclohexene after 100 h of continuous reaction in the reactor

[0104] Catalyst Benzene conversion (%) Cyclohexene selectivity (%) Cyclohexene yield (%) Catalyst 1 54.69 83.47 45.65 Catalyst 2 53.86 84.35 45.43 Catalyst 3 54.12 84.01 45.47 Catalyst 4 53.82 84.20 45.32

[0105] As can be seen from Table 1 and Table 2, the porous polyamide carrier catalysts 1-4 prepared in the application have high activity and high cyclohexene selectivity, and have good stability in the reaction of partial hydrogenation of benzene to prepare cyclohexene, whether in a batch reaction or in a continuous reaction, which makes the porous polyamide carrier catalysts 1-4 prepared in the application have very broad application prospects and economic value in the industrial production of partial hydrogenation of benzene to prepare cyclohexene.

[0106] Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing examples, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A benzene partial hydrogenation catalyst, wherein The catalyst uses porous polyamide as a carrier, ruthenium metal as a main active component, and includes one or more auxiliary components selected from boron, zinc, aluminum, iron, molybdenum, platinum, nickel, lanthanum, cerium, copper, and cobalt.

2. The catalyst according to claim 1, wherein The mass ratio of ruthenium to the porous polyamide carrier in the catalyst is 1%-50%, preferably 15%; and / or The auxiliary agent component is selected from boron, zinc, cerium; and / or The mass ratio of ruthenium, boron, zinc and cerium in the catalyst is 1:0.1-20:0.1-50:0.1-20, preferably 1:0.5:25:5; and / or The BET specific surface area of ​​the porous polyamide is 25-35 m 2 / g, average pore diameter of 25-35nm, total pore volume of 0.15-0.25cm 3 / g; and / or The particle size D50 of the catalyst is 15-25 μm.

3. A method for preparing a benzene partial hydrogenation catalyst, the method comprising: S1, Preparation of porous polyamide support The diamine monomer and the porogen are mixed and dissolved in an organic solvent, and then a dibasic acid chloride solution dissolved in the organic solvent is added and mixed to cause the reaction solution to undergo a polymerization reaction to form a polyamide; the porogen is then removed with a non-solvent, and the porous polyamide support is washed with water and dried; S2, Preparation of Catalyst The porous polyamide support prepared in S1, the main active ingredient ruthenium metal salt, and the auxiliary compound (such as salt) are placed in water, stirred at room temperature, and then slowly heated to remove water to obtain a solid; the solid is placed in a hydrogen atmosphere for heating and reduction; washed with water, dried, and calcined in an inert atmosphere to obtain the catalyst.

4. The method according to claim 3, wherein: The dibasic acid chloride in S1 is prepared by the following steps S0: S0, dissolving the dibasic acid in an organic solvent, then adding an acyl halide reagent at room temperature, and after the addition of the acyl halide reagent is complete, heating the reaction solution to start the reaction until the reaction is complete to obtain a dibasic acid chloride solution; In particular, in S0, The acyl halide reagent is one or more selected from thionyl chloride, phosphorus trichloride, phosphorus pentachloride, oxalyl chloride, carbon tetrachloride, phosphorus tribromide, preferably oxalyl chloride; and / or The dibasic acid is selected from an aliphatic dibasic acid or an aromatic dibasic acid, in particular, the aliphatic dibasic acid is one or more selected from oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, maleic acid and fumaric acid; the aromatic dibasic acid is one or more selected from phthalic acid, isophthalic acid, terephthalic acid, 2,6-naphthalene dicarboxylic acid and 4,4'-biphenyl dicarboxylic acid; more particularly, the aliphatic dibasic acid is selected from adipic acid, and the aromatic diamine is selected from terephthalic acid; and / or The molar ratio of the dibasic acid to the acyl halide reagent is 1:0.5-1:10, preferably 1:2-1:4; and / or The reaction heating temperature is 30°C-60°C, preferably 40°C-50°C, more preferably 45°C; and / or The reaction time is 0.5h-12h, preferably 3h-5h.

5. The method according to claim 3 or 4, wherein: In S1, The diamine monomer is selected from aliphatic diamines or aromatic diamines, in particular, the aliphatic diamine is selected from one or more of ethylenediamine, butanediamine, pentamethylenediamine, hexamethylenediamine, and diaminopropane; the aromatic diamine is selected from one or more of diphenylethylenediamine, xylenediamine, o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 4,4'-diaminobiphenyl, and 1,8-diaminonaphthalene; more particularly, the aliphatic diamine is selected from hexamethylenediamine, and the aromatic diamine is selected from p-phenylenediamine; and / or The porogen is one or more selected from polyethylene glycol (PEG, molecular weight 400-6000), polyvinyl pyrrolidone, lithium chloride, calcium chloride, preferably PEG-1000; and / or The porogen accounts for 5% to 40% by mass of the diamine, preferably 10%; and / or The polymerization temperature is 40°C to 100°C, preferably 70°C; and / or The polymerization reaction time is 1 h to 12 h, preferably 6 h; and / or After the polymerization reaction is completed, the polymer solution is cast into a membrane and then immersed in a non-solvent bath to completely exchange the solvent, porogen and non-solvent to form a porous structure; and / or Wash with water 3-5 times and freeze-dry; and / or The non-solvent is selected from a water / ethanol mixture, a water / methanol mixture, a water / ethylene glycol mixture and a water / acetic acid mixture, preferably a water / ethanol mixture; and / or The immersion time in the non-solvent bath is 10 h to 72 h, preferably 48 h.

6. The method according to claim 5, wherein: The molar ratio of the diamine monomer in S1 to the dibasic acid used to prepare the dibasic acid chloride in S0 is 1:0.1-1:10, preferably 1:1; and / or In S1, first, the diamine and the porogen are uniformly mixed in an organic solvent, and then the organic solvent is slowly mixed with the prepared dibasic acid chloride solution at -10°C to 10°C, preferably 0°C to 5°C; and / or In S1, the volume ratio of water to ethanol in the water / ethanol mixture is 1:0.1-1:10, preferably 1:1; and / or In S1, the freeze-drying temperature is -100°C to -20°C, preferably -50°C; and / or In S1, the freeze-drying time is 12-48 hours, preferably 24 hours.

7. The method according to any one of claims 3 to 6, wherein: In S2, The ruthenium metal salt is one or two selected from ruthenium trichloride trihydrate, ruthenium nitrate, ruthenium acetate, potassium hexachlororuthenate, potassium hexacyanoruthenate, potassium ruthenate, ruthenium tribromide, ruthenium nitrosyl nitrate and ruthenium acetylacetonate, preferably ruthenium trichloride trihydrate; and / or The mass ratio of the ruthenium content in the ruthenium metal salt to the porous polyamide carrier is 1%-50%, preferably 15%; and / or The auxiliary agent is one or more selected from boron, zinc, aluminum, iron, molybdenum, platinum, nickel, lanthanum, cerium, copper, and cobalt, preferably selected from boron, zinc, and cerium; and / or Ultrasonic stirring is used, and the ultrasonic stirring time is 5h-24h; and / or Heating rate of 0.1-5°C / min; and / or Raising the temperature to remove water to a target temperature of 60°C to 110°C; and / or Heating in a hydrogen atmosphere at a temperature of 100°C to 300°C; and / or The heating reduction time in hydrogen atmosphere is 5-48h; and / or Drying is vacuum drying at a temperature of 50°C-100°C; and / or Drying is vacuum drying, and the drying time is 5h-24h; and / or The inert atmosphere is argon atmosphere, and the calcination temperature is 100°C-300°C; and / or The inert atmosphere is argon atmosphere, and the calcination time is 1h-12h.

8. The method according to claim 7, wherein: Boron in the additive comes from boric acid, borax; and / or The zinc in the additive is from one or two of zinc sulfate heptahydrate, zinc chloride, zinc bromide, zinc iodide, zinc acetate, and zinc nitrate; and / or The cerium in the additive is one or two of cerium trichloride, cerium sulfate, cerium nitrate, cerium acetate, and cerium oxalate; and / or The mass ratio of ruthenium, boron, zinc and cerium is 1:0.1-20:0.1-50:0.1-20, preferably 1:0.5:25:

5.

9. A method for preparing cyclohexene using the catalyst according to claim 1 or 2 or a catalyst prepared by the method according to any one of claims 3 to 7, comprising the following steps: The catalyst is mixed with benzene and reacted in a hydrogen atmosphere to obtain cyclohexene.

10. The method according to claim 9, wherein: The catalyst accounts for 1% to 40% by mass of benzene; and / or The volume ratio of benzene to water is 1:1-1:5; and / or The molar ratio of benzene to hydrogen is 1:1 to 1:6; and / or The reaction pressure is 2 MPa-6 MPa; and / or The reaction temperature is 120°C-180°C; and / or The reaction time is 10 min-90 min.

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