A catalyst for dehydrogenation of 1,4-butanediol to gamma-butyrolactone and a preparation method thereof

Abstract

The application provides a catalyst for preparing gamma-butyrolactone by dehydrogenation of 1,4-butanediol and a preparation method thereof. The method comprises the following steps: adding a copper-containing compound into ammonia water to obtain a copper-ammonia solution; impregnating a silicon dioxide powder carrier with the copper-ammonia solution, hydrothermally treating the powder carrier, drying and calcining to obtain a powder; mixing the crushed powder with alpha, beta-aluminum oxide powder, lithium carboxymethyl cellulose and sesbania powder to obtain mixed powder 1; adding an amino silane oligomer into a silica sol to obtain a binder 1, adding the binder 1 into the mixed powder 1, shaping, drying and calcining to obtain a modified carrier; impregnating the modified carrier with an aqueous solution containing Cr and Pd compounds, drying and calcining to obtain the target catalyst. The catalyst has high strength, weak acidity, high dispersion of active components and good mass transfer performance, and has excellent activity and selectivity when used for preparing gamma-butyrolactone by dehydrogenation of 1,4-butanediol.

Description

TECHNICAL FIELD

[0001] The present application relates to a catalyst for preparing gamma-butyrolactone by dehydrogenation of 1,4-butanediol and a preparation method thereof, and belongs to the field of catalysis technology. BACKGROUND

[0002] Gamma-butyrolactone is an important fine chemical intermediate, mainly used for producing NMP (N-methyl pyrrolidone), other pyrrolidone compounds (NVP, PVP, etc.) and acetyl butyrolactone, etc. In addition, it is also an excellent high-boiling organic solvent with strong solubility, good conductivity and good stability.

[0003] The production methods of gamma-butyrolactone mainly include furfural method, direct hydrogenation of maleic anhydride method, esterification hydrogenation of maleic anhydride method and dehydrogenation of 1,4-butanediol method, etc. The process route of preparing gamma-butyrolactone by oxidation-hydrogenation of furfural is complex, and the raw material price is relatively high, so the economic efficiency is poor, and it has been eliminated. The direct hydrogenation of maleic anhydride method has relatively high acidity in the crude product, which causes great corrosion to the equipment and makes it difficult to separate the by-products. The esterification hydrogenation of maleic anhydride method has a complex process route and high investment cost. The dehydrogenation of 1,4-butanediol to prepare gamma-butyrolactone has low raw material cost, simple process flow and easy separation of products, so it is the preferred production route of gamma-butyrolactone.

[0004] Currently, 1,4-butanediol is usually used to prepare gamma-butyrolactone by atmospheric pressure dehydrogenation in industry. However, the reactor volume and the diameter of the material conveying pipeline are relatively large during atmospheric pressure dehydrogenation, so it is difficult to build a larger scale device. The conventional atmospheric pressure dehydrogenation catalyst has problems such as poor selectivity and stability when used for pressurized dehydrogenation, so it is of great significance to develop a dehydrogenation catalyst suitable for pressurized process.

[0005] Currently, the catalysts for preparing gamma-butyrolactone by dehydrogenation of 1,4-butanediol have been reported in many patents, mainly including Cu-based catalysts.

[0006] Patent CN102580756B discloses a catalyst for preparing gamma-butyrolactone by dehydrogenation of 1,4-butanediol and a preparation method thereof. The catalyst is a Cu-Cr-Ti catalyst prepared by co-precipitation method. The molar ratio of hydrogen to alcohol used in the evaluation of the catalyst is high, and the selectivity of gamma-butyrolactone (about 97%) is low.

[0007] Patent CN102886263A discloses a catalyst for preparing gamma-butyrolactone by dehydrogenation and a preparation method thereof. The patent uses a conventional impregnation method to prepare a Cu-Si-Ca / Sr / Ba catalyst, and the selectivity of gamma-butyrolactone is about 99% under atmospheric pressure.

[0008] Patent CN1045174 discloses a catalyst for preparing gamma-butyrolactone by dehydrogenation of 1,4-butanediol. The catalyst is a Cu-Zn-Al-Pt / Pd system, and the selectivity of gamma-butyrolactone is about 97% under atmospheric pressure.

[0009] CN1094789C discloses a catalyst for preparing gamma-butyrolactone by dehydrogenation of 1,4-butanediol and its use. The catalyst is Cu-Zn-Al-Ba / Pd prepared by coprecipitation method. The conversion rate is close to 100% and the selectivity is >96% when used for dehydrogenation of 1,4-butanediol under normal pressure.

[0010] European patent EP507023 reports a catalyst for preparing gamma-butyrolactone by gas phase dehydrogenation of 1,4-butanediol, which is Cu-Cr-Mn-Ba system. The conversion rate of 1,4-butanediol is 98.1% and the selectivity of gamma-butyrolactone is 99.1% when the reaction is carried out under normal pressure at 230℃.

[0011] Japanese patent JP3232874 reports a Cu-Cr-Ba catalyst, which has a 1,4-butanediol conversion rate of 98.1% and a gamma-butyrolactone selectivity of 99.1% under normal pressure at 230℃.

[0012] None of the above patents mentions the dehydrogenation performance of the catalyst under pressure. Pressurized reaction can greatly promote the occurrence of side reactions such as hydrogenolysis of 1,4-butanediol to produce n-butanol, resulting in a significant decrease in the yield of gamma-butyrolactone.

[0013] Currently, the catalysts for preparing gamma-butyrolactone by dehydrogenation of 1,4-butanediol prepared by existing technologies are mostly used for normal pressure reaction. When used for pressurized dehydrogenation reaction, there are problems such as many side reactions, low yield of gamma-butyrolactone, and easy pulverization of the catalyst under abnormal process conditions. Therefore, it is of great significance to develop a catalyst suitable for pressurized dehydrogenation for preparing gamma-butyrolactone, which has excellent reaction performance. SUMMARY

[0014] One of the purposes of the present application is to provide a preparation method of a catalyst for preparing gamma-butyrolactone by dehydrogenation of 1,4-butanediol. The catalyst prepared by the method has excellent activity and selectivity.

[0015] To achieve the above purpose, the present application adopts the following technical solutions:

[0016] A method for preparing a catalyst for preparing gamma-butyrolactone by dehydrogenation of 1,4-butanediol, the method comprising the following steps:

[0017] S1: adding a copper-containing compound into ammonia water to obtain a copper-ammonia solution;

[0018] S2: impregnating a silica powder carrier with the copper-ammonia solution, hydrothermally treating the powder carrier, drying and calcining to obtain a powder;

[0019] S3: mixing the crushed powder with α,β-alumina powder, lithium carboxymethyl cellulose and sesbania powder to obtain a mixed powder 1;

[0020] S4: adding the amino silane oligomer into the silica sol to obtain a binder 1, adding the binder 1 into the mixed powder 1, shaping, drying, and calcining to obtain a modified carrier;

[0021] S5: immersing the modified carrier into an aqueous solution containing Cr and Pd compounds, drying, and calcining to obtain the target catalyst.

[0022] In the present application, in the preparation method of the catalyst, the silica carrier is first immersed with a copper compound solution and subjected to hydrothermal treatment, which improves the interaction between the carrier and the active component and plays a pore-expanding role; the addition of the α,β-aluminum oxide during shaping is conducive to the diffusion of raw materials and products; the addition of lithium carboxymethyl cellulose during shaping is conducive to inhibiting the acidity of the catalyst, improving the diffusion performance, and improving the selectivity; the addition of the amino silane oligomer weakens the acidity of the carrier and is conducive to inhibiting the occurrence of dehydration side reactions; the Cr and Na assistants for impregnation can reduce the acidity of the carrier and improve the stability of the catalyst; the introduction of Pd significantly improves the activity of the catalyst and can inhibit the generation of heavy components. The prepared catalyst has high dispersion of the active component, strong interaction between the active component and the carrier, and excellent activity, selectivity, and stability when used for preparing γ-butyrolactone from 1,4-butanediol.

[0023] In an embodiment of the present application, the copper compound in S1 is one or more of copper salts and / or copper bases, preferably one or more of copper nitrate, copper chloride, copper hydroxide, and basic copper carbonate.

[0024] In an embodiment of the present application, the concentration of the ammonia water in S1 is 15-25wt%.

[0025] In an embodiment of the present application, the molar ratio of the copper compound to NH3 in the ammonia water in S1 is 1:(4-6).

[0026] In an embodiment of the present application, the specific surface area of the silica powder in S2 is 100-400m 2 / g, the pore volume is 0.5-1.2g / ml, and the average pore size is 6-15nm.

[0027] In an embodiment of the present application, the mass ratio of Cu in the copper ammonia solution to the silica powder carrier in S2 is 1:(4-6).

[0028] In an embodiment of the present application, the temperature of the hydrothermal treatment in S2 is 110-160℃, and the hydrothermal treatment time is 4-12h.

[0029] In an embodiment of the present application, the drying temperature in S2 is 100-120℃, and the drying time is 4-12h.

[0030] In one embodiment of the present application, the calcination temperature of S2 is 300-450℃, and the calcination time is 2-8h.

[0031] In one embodiment of the present application, the mass ratio of the powder, the α,β-alumina powder, the lithium carboxymethyl cellulose, and the sesbania powder of S3 is 1:(0.1-0.3):(0.03-0.15):(0.03-0.05).

[0032] In one embodiment of the present application, the particle size of the α,β-alumina powder of S3 is 80-150 mesh.

[0033] In one embodiment of the present application, the particle size of the lithium carboxymethyl cellulose of S3 is >200 mesh.

[0034] In one embodiment of the present application, the amino silane oligomer of S4 is an aqueous amino silane oligomer, preferably comprising one or more of the commercially available products 8150, QX-1250 amino silane oligomer, KRN8025, and 1146 amino silane oligomer of Ganzhou Silica Industry Co., Ltd.; preferably, the amino silane oligomer is added in an amount of 0.5-5.0wt% of the mass of the silica sol.

[0035] In one embodiment of the present application, the silica sol of S4 is an alkaline silica sol; preferably, the silica sol has a concentration of 30-40wt% and a particle size of 20-40nm.

[0036] In one embodiment of the present application, the mass ratio of the mixed powder 1 and the binder 1 of S4 is 1:(0.5-0.8).

[0037] In one embodiment of the present application, the drying temperature of S4 is 100-120℃, and the drying time is 4-12h.

[0038] In one embodiment of the present application, the calcination temperature of S4 is 400-550℃, and the calcination time is 2-8h.

[0039] In one embodiment of the present application, the modified carrier prepared by S4 has a diameter of 3.0-5.0mm and a length of 3.0-5.0mm.

[0040] In one embodiment of the present application, the Cr-containing compound of S5 is chromium oxide and / or a chromate, preferably one or more of CrO3, sodium chromate, and sodium dichromate.

[0041] In one embodiment of the present application, the Pd-containing compound of S5 is a water-soluble palladium salt and / or a chromium salt, preferably one or more of palladium chloride, palladium nitrate, and dichlorotetraammine palladium.

[0042] In one embodiment of the present application, preferably, the concentration of Cr in the aqueous solution of Cr and Pd compound is 0.6-3.0 wt%, and the concentration of Pd is 0.05-0.3 wt%.

[0043] In one embodiment of the present application, the mass ratio of the modified carrier to the aqueous solution in S5 is 1:(0.83-0.90).

[0044] In one embodiment of the present application, the drying temperature in S5 is 100-120℃, and the drying time is 4-12h.

[0045] In one embodiment of the present application, the calcination temperature in S5 is 450-600℃, and the calcination time is 2-8h.

[0046] Another object of the present application is to provide a catalyst for preparing γ-butyrolactone by dehydrogenation of 1,4-butanediol.

[0047] A catalyst for preparing γ-butyrolactone by dehydrogenation of 1,4-butanediol, which is prepared by the above method, and contains the following components in the total mass of 100 wt%:

[0048]

[0049] Still another object of the present application is to provide a use of the dehydrogenation catalyst.

[0050] A use of the dehydrogenation catalyst, which is prepared by the above method, or is the above catalyst, for the dehydrogenation reaction of alcohol, preferably for the reaction of preparing γ-butyrolactone by dehydrogenation of 1,4-butanediol, more preferably for the reaction of preparing γ-butyrolactone by dehydrogenation of 1,4-butanediol under the reaction pressure of 0.3-0.5 atm.

[0051] For example, the catalyst of the present application is used in the process of preparing γ-butyrolactone by pressurized dehydrogenation of 1,4-butanediol: the catalyst evaluation is carried out by using a fixed bed device, the inner diameter of the reaction tube is 25-40mm, the loading amount of the whole-sized catalyst is 30-200ml, and the set temperature is 200-250℃; the molar ratio of hydrogen to alcohol is 10-30:1; the reaction pressure is 0.5atm; the mass space velocity of 1,4-butanediol is 0.1-0.6h -1 .

[0052] Compared with the prior art, the present application has the following advantages:

[0053] The catalyst prepared by the method has weak acidity, good diffusion performance, high dispersion of active components and good stability, effectively inhibits the occurrence of side reactions when used for preparing gamma-butyrolactone from 1,4-butanediol under pressurized conditions, and the conversion rate of BDO and the selectivity of gamma-butyrolactone are both >99.0%. DETAILED DESCRIPTION

[0054] In order to enable a detailed understanding of the technical features and content of the present application, the preferred embodiments of the present application will be described in more detail below. Although the preferred embodiments of the present application are described in the examples, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments described herein.

[0055] <Raw material source>

[0056] 1,4-butanediol, analytical pure, purchased from Shanghai Aldrin Biochemical Technology Co., Ltd.;

[0057] Silicon dioxide, analytical pure, purchased from Shanghai Aldrin Biochemical Technology Co., Ltd.;

[0058] Copper nitrate, analytical pure, purchased from Shanghai Aldrin Biochemical Technology Co., Ltd.;

[0059] Sodium chromate, analytical pure, purchased from Shanghai Aldrin Biochemical Technology Co., Ltd.;

[0060] Quartz powder, >98%, purchased from Beijing Inokai Technology Co., Ltd., particle size 80-150 mesh;

[0061] Carboxymethyl cellulose lithium, >98%, purchased from Beijing Inokai Technology Co., Ltd.;

[0062] Alpha-beta alumina, Al2O3 94.4%, Na2O 3.7%, purchased from Beijing Inokai Technology Co., Ltd.;

[0063] Aminosilane oligomer, SiO2 content 40-45%, purchased from Beijing Inokai Technology Co., Ltd.;

[0064] Alkaline silica sol, concentration 30-40 wt%, purchased from Linyi Kohan Silicon Products Co., Ltd.;

[0065] Sodium chloropalladate, analytical pure, purchased from Shanghai Aldrin Biochemical Technology Co., Ltd.

[0066] <Testing method>

[0067] The conversion rate of 1,4-butanediol and the selectivity of γ-butyrolactone were calculated after analysis using an Agilent 7820A gas chromatograph. The test conditions included: DB-5 column, FID detector, vaporization chamber temperature of 260℃, detector temperature of 260℃, carrier gas of high-purity N2, and flow rate of 30 ml / min.

[0068] Example 1

[0069] (1) Add 79.0g of copper nitrate to 167.0g of 15wt% ammonia water and stir thoroughly to obtain a copper ammonia solution;

[0070] (2) Mix the copper ammonia solution obtained in step (1) with 120.0g of silica powder carrier (specific surface area 150m²). 2 Mix the above mixture (0.65 g / ml pore volume, 12 nm average pore size) and stir thoroughly; then place the mixture into a hydrothermal reactor for closed hydrothermal treatment, during which the hydrothermal reactor is rotated at 120 r / min and treated at 120℃ for 12 h; then transfer the material in the hydrothermal reactor to a 100℃ oven for drying for 12 h, and then calcine at 350℃ for 4 h.

[0071] (3) The powder after calcination in step (2) is pulverized to the 100-mesh sieve and then thoroughly mixed with 40.0g of α-β alumina (particle size between 110-150 mesh sieve), 20g of lithium carboxymethyl cellulose (220 mesh), and 6.0g of guar gum powder to obtain a mixed powder.

[0072] (4) Add 2.66g of aqueous aminosilane oligomer to 133.3g of 30wt% silica sol (20nm). 8150, stir thoroughly to obtain binder; add binder to the mixed powder in step (3), knead thoroughly for 30 minutes, extrude into strips and cut into pellets, dry at 100℃ for 12 hours, and calcine at 400℃ for 4 hours to obtain a carrier with a diameter of 3.0 mm and a length of 3.0 mm;

[0073] (5) Dissolve 1.3g sodium chloropalladium and 6.5g sodium chromate in 160g water to obtain an impregnation solution. Then spray the impregnation solution onto the carrier obtained in step (4), dry at 100℃ for 12h, and calcine at 450℃ for 4h to obtain catalyst A.

[0074] Catalyst reduction: Catalyst A was loaded into a fixed-bed hydrogenation reactor with an inner diameter of 30 mm and a catalyst loading of 100 ml. Before use, the catalyst was reduced under a nitrogen and hydrogen mixture, maintaining a mixed gas hourly space velocity (VHSV) of 300 h⁻¹ during the reduction process. -1The reactor temperature was first raised to 160°C and held for 2 h to remove the physical water adsorbed by the catalyst, then a mixture of hydrogen and nitrogen with a hydrogen volume fraction of 5% was introduced for pre-reduction for 1 h, after which the hydrogen fraction in the hydrogen and nitrogen mixture was gradually increased to 10%, 20%, 50%, and 100%, and the hot spot temperature of the catalyst bed was controlled to be no more than 250°C, and finally the temperature was raised to 250°C and reduced in a pure hydrogen atmosphere for 4 h.

[0075] Catalyst performance evaluation:

[0076] The catalyst evaluation was performed using a fixed bed device, the reaction tube had a diameter of 35 mm, the whole size catalyst loading was 100 ml, the set temperature was 220°C; the hydrogen / alcohol molar ratio was 10:1; the reaction pressure was 0.5 atm; the 1,4-butanediol mass space velocity was 0.3 h -1 , and the reaction feed was sampled and analyzed after being stabilized for 4 h. The reaction results are shown in Table 1.

[0077] Example 2

[0078] (1) 85.0 g of copper nitrate was added to 149.9 g of 20 wt% ammonia water and stirred to obtain a copper ammonia solution;

[0079] (2) The copper ammonia solution obtained in step (1) was mixed with 124.0 g of a silica powder carrier (specific surface area 350 m 2 / g, pore volume 0.9 g / ml, average pore diameter 7 nm) and stirred uniformly; then the mixture was placed in a hydrothermal kettle for sealed hydrothermal treatment, the hydrothermal kettle was kept rotating at 120 r / min during the treatment, and the temperature was kept at 130°C for 6 h; after that, the material in the hydrothermal kettle was transferred to a 110°C oven for drying for 8 h, and then calcined at 300°C for 8 h;

[0080] (3) The powder after calcination in step (2) was crushed to 100 mesh and mixed with 36.0 g of α-β alumina (particle size 80-100 mesh), 16.7 g of lithium carboxymethyl cellulose (300 mesh), and 6.0 g of sesbania powder to obtain a mixed powder;

[0081] (4) 1.0 g of an aqueous aminosilane oligomer QX-1250 was added to 100.0 g of a 40 wt% silica sol (20 nm) and stirred to obtain a binder; the binder was added to the mixed powder in step (3) and kneaded for 30 minutes, extruded and cut into particles, dried at 110°C for 5 h, and calcined at 550°C for 2 h to obtain a carrier with a diameter of 4.0 mm and a length of 4.0 mm;

[0082] (5) 1.2 g of sodium chloropalladate and 3.2 g of sodium chromate were dissolved in 160 g of water to obtain an impregnation solution, which was then sprayed onto the carrier obtained in step (4) and dried at 110°C for 6 h and calcined at 450°C for 6 h to obtain catalyst B.

[0083] The catalyst evaluation process conditions and operation process refer to Example 1.

[0084] Example 3

[0085] (1) 97.2 g of copper nitrate was added to 228.4 g of 15wt% ammonia water and stirred to obtain a copper ammonia solution;

[0086] (2) The copper ammonia solution obtained in step (1) was mixed with 128.0 g of silica powder carrier (specific surface area 150 m 2 / g, pore volume 0.65 g / ml, average pore size 12 nm) and stirred uniformly; then the mixture was placed in an autoclave for closed hydrothermal treatment, during which the autoclave was kept rotating at 120 r / min, and treated at 140°C for 6 h; then the material in the autoclave was transferred to a 120°C oven for drying for 6 h, and then calcined at 450°C for 2 h;

[0087] (3) The powder after calcination in step (2) was crushed to 100 mesh and mixed with 32.0 g of α-β alumina (particle size 110-150 mesh), 13.3 g of lithium carboxymethyl cellulose (220 mesh), and 6.0 g of sesbania powder to obtain a mixed powder;

[0088] (4) 4.0 g of aqueous aminosilane oligomer KRN8025 was added to 133.3 g of 30wt% silica sol (25 nm) and stirred to obtain a binder; the binder was added to the mixed powder in step (3) and kneaded for 30 min, extruded and cut into particles, dried at 110°C for 4 h, and calcined at 400°C for 6 h to obtain a carrier with a diameter of 5.0 mm and a length of 5.0 mm;

[0089] (5) 1.0 g of sodium chloropalladate and 9.7 g of sodium chromate were dissolved in 160 g of water to obtain an impregnation solution, which was then sprayed onto the carrier obtained in step (4) and dried at 120°C for 6 h and calcined at 600°C for 2 h to obtain catalyst C.

[0090] The catalyst evaluation process conditions and operation process refer to Example 1.

[0091] Example 4

[0092] (1) 109.3 g of copper nitrate was added to 214.1 g of 18wt% ammonia water and stirred to obtain a copper ammonia solution;

[0093] (2) The copper ammonia solution obtained in step (1) was mixed with 132.0 g of silica powder support (specific surface area 350 m 2 / g, pore volume 0.9 g / ml, average pore diameter 7 nm) and stirred thoroughly; then the mixture was placed in an autoclave for closed hydrothermal treatment, during which the autoclave was kept rotating at 120 r / min, treated at 150 °C for 4 h; after that, the material in the autoclave was transferred to a 110 °C oven for drying for 8 h, and then calcined at 350 °C for 4 h;

[0094] (3) The powder after calcination in step (2) was crushed to 100 mesh sieve residue and mixed thoroughly with 28.0 g of α-β alumina (particle size 80-100 mesh sieve interval), 10.0 g of lithium carboxymethyl cellulose (300 mesh), and 6.0 g of sesbania powder to obtain a mixed powder;

[0095] (4) 4.0 g of aqueous aminosilane oligomer, Fullersil 1146 aminosilane oligomer, was added to 100.0 g of 40 wt% silica sol (20 nm) and stirred thoroughly to obtain a binder; the binder was added to the mixed powder in step (3) and thoroughly kneaded for 30 min, extruded and cut into pellets, dried at 120 °C for 4 h, and calcined at 450 °C for 4 h to obtain a support with a diameter of 3.0 mm and a length of 3.0 mm;

[0096] (5) 0.6 g of sodium chloropalladate and 12.3 g of sodium chromate were dissolved in 160 g of water to obtain an impregnation solution, which was then sprayed onto the support obtained in step (4), dried at 120 °C for 4 h, and calcined at 450 °C for 6 h to obtain catalyst D.

[0097] The process conditions and operating procedures for catalyst evaluation were the same as in Example 1.

[0098] Example 5

[0099] (1) 115.4 g of copper nitrate was added to 223.7 g of 20 wt% ammonia water and stirred thoroughly to obtain a copper ammonia solution;

[0100] (2) The copper ammonia solution obtained in step (1) was mixed with 136.0 g of silica powder support (specific surface area 150 m 2 / g, pore volume 0.65 g / ml, average pore diameter 12 nm) and stirred thoroughly; then the mixture was placed in an autoclave for closed hydrothermal treatment, during which the autoclave was kept rotating at 150 r / min, treated at 120 °C for 4 h; after that, the material in the autoclave was transferred to a 120 °C oven for drying for 6 h, and then calcined at 350 °C for 6 h;

[0101] (3) The powder after calcination in step (2) was crushed to 100 mesh sieve and mixed with 24.0 g of α-β alumina (particle size 110-150 mesh), 6.7 g of lithium carboxymethyl cellulose (220 mesh), and 6.0 g of sesbania powder to obtain a mixed powder;

[0102] (4) 6.0 g of aqueous amino silane oligomer KRN8025 was added to 133.3 g of 30 wt% silica sol (30 nm) and stirred to obtain a binder; the binder was added to the mixed powder in step (3) and kneaded for 30 minutes, extruded and cut into pellets, dried at 110°C for 8 h, and calcined at 500°C for 4 h to obtain a carrier with a diameter of 4.0 mm and a length of 4.0 mm;

[0103] (5) 0.4 g of sodium palladium chloride and 13.6 g of sodium chromate were dissolved in 160 g of water to obtain an impregnation solution, which was then sprayed onto the carrier obtained in step (4) and dried at 120°C for 4 h and calcined at 550°C for 4 h to obtain catalyst E.

[0104] The process conditions and operation process for catalyst evaluation were the same as in Example 1.

[0105] Comparative Example 1

[0106] The steps for preparing a 1,4-butanediol dehydrogenation catalyst were the same as in Example 1, except that no amino silane oligomer was added in step (4), and catalyst G was obtained.

[0107] The process conditions and operation process for catalyst evaluation were the same as in Example 1.

[0108] Comparative Example 2

[0109] The steps for preparing a 1,4-butanediol dehydrogenation catalyst were the same as in Example 1, except that no sodium palladium chloride was added in step (4), and catalyst H was obtained.

[0110] The process conditions and operation process for catalyst evaluation were the same as in Example 1.

[0111] Comparative Example 3

[0112] The steps for preparing a 1,4-butanediol dehydrogenation catalyst were the same as in Example 1, except that no sodium chromate was added in step (4), and catalyst I was obtained.

[0113] The process conditions and operation process for catalyst evaluation were the same as in Example 1.

[0114] Comparative Example 4

[0115] The steps for preparing a 1,4-butanediol dehydrogenation catalyst were the same as in Example 1, except that no α-β alumina powder was added in step (3), and catalyst J was obtained.

[0116] The catalyst evaluation process conditions and operation process refer to Example 1.

[0117] Comparative Example 5

[0118] The preparation of the 1,4-butanediol dehydrogenation catalyst was the same as in Example 1, except that in step (3) lithium carboxymethyl cellulose was not added, and catalyst K was prepared.

[0119] The catalyst evaluation process conditions and operation process refer to Example 1.

[0120] Table 1 Catalyst evaluation results

[0121]

[0122]

[0123] As can be seen from Table 1, catalysts A to E have good activity and selectivity, while the catalysts described in Comparative Examples 1 to 6 either have low activity or poor γ-butyrolactone selectivity. The above results show that the catalyst prepared by the present application has good synergistic effect, high dispersion of active components, weak acidity, good mass transfer performance, and excellent activity and selectivity when used for the dehydrogenation of 1,4-butanediol to prepare γ-butyrolactone.

[0124] By comparing Example 1 and Comparative Example 1, it is shown that the introduction of the aqueous amino silane oligomer is beneficial to reducing the acidity of the catalyst and improving the selectivity of the catalyst.

[0125] By comparing Example 1 and Comparative Example 2, it is shown that the introduction of Pd in the catalyst is beneficial to improving the activity and selectivity of the catalyst.

[0126] By comparing Example 1 and Comparative Example 3, it is shown that the introduction of Cr in the catalyst is beneficial to improving the dispersion of Cu and inhibiting the generation of by-products, which is beneficial to the activity and selectivity of the catalyst.

[0127] By comparing Example 1 and Comparative Example 4, it is shown that the use of α-β alumina powder with a suitable particle size improves the diffusion performance of the catalyst, inhibits the acidity of the catalyst, and improves the conversion of 1,4-butanediol and the selectivity of γ-butyrolactone.

[0128] By comparing Example 1 and Comparative Example 5, it is shown that the addition of lithium carboxymethyl cellulose is beneficial to inhibiting the acidity of the catalyst, improving the mass transfer performance of the catalyst, and improving the conversion of 1,4-butanediol and the selectivity of γ-butyrolactone.

Claims

1. A method for producing a catalyst for dehydrogenation of 1,4-butanediol to γ-butyrolactone, characterized by, The preparation method comprises the following steps: S1: adding a copper-containing compound into ammonia water to obtain a copper-ammonia solution; S2: impregnating a silica powder carrier with the copper-ammonia solution, hydrothermally treating the powder carrier, drying, and calcining to obtain a powder; S3: mixing the crushed powder with α, β-alumina powder, lithium carboxymethyl cellulose, and sesbania powder to obtain a mixed powder 1; S4: adding an aminosilane oligomer into a silica sol to obtain a binder 1, adding the binder 1 into the mixed powder 1, shaping, drying, and calcining to obtain a modified carrier; S5: impregnating the modified carrier with an aqueous solution containing Cr and Pd compounds, drying, and calcining to obtain a target catalyst.

2. The production method according to claim 1, characterized by, The copper-containing compound in S1 is a copper salt and / or a copper base; And / or, the concentration of the ammonia water in S1 is 15-25wt%; And / or, the molar ratio of the copper compound to NH3 in the ammonia water in S1 is 1:(4-6).

3. The preparation method according to claim 2, characterized in that, The copper-containing compound in S1 is one or more of copper nitrate, copper chloride, copper hydroxide, and basic copper carbonate.

4. The method of claim 1, wherein, S2 the specific surface area of the silica powder is 100-400 m 2 / g, pore volume 0.5-1.2 g / ml, average pore diameter 6-15 nm; And / or, the mass ratio of Cu in the copper-ammonia solution to the silica powder carrier in S2 is 1:(4-6); And / or, the temperature of the hydrothermal treatment in S2 is 110-160℃, and the hydrothermal treatment time is 4-12h; And / or, the drying temperature in S2 is 100-120℃, and the drying time is 4-12h; And / or, the calcining temperature in S2 is 300-450℃, and the calcining time is 2-8h.

5. The preparation method according to claim 1, characterized in that, The mass ratio of the powder, the α, β-alumina powder, the lithium carboxymethyl cellulose, and the sesbania powder in S3 is 1:(0.1-0.3):(0.03-0.15):(0.03-0.05); And / or, the particle size of the α, β-alumina powder in S3 is 80-150 mesh; And / or, the particle size of the lithium carboxymethyl cellulose in S3 is >200 mesh.

6. The method of claim 1, wherein, The aminosilane oligomer in S4 is an aqueous aminosilane oligomer; And / or, the silica sol in S4 is an alkaline silica sol; And / or, the mass ratio of the mixed powder 1 to the binder 1 in S4 is 1:(0.5-0.8); And / or, the drying temperature in S4 is 100-120℃, and the drying time is 4-12h; And / or, the calcining temperature in S4 is 400-550℃, and the calcining time is 2-8h; And / or, the diameter of the modified carrier prepared in S4 is 3.0-5.0mm, and the length of the carrier is 3.0-5.0mm.

7. The production method according to claim 6, characterized by, S4 the aminosilane oligomer comprises a commercially available product 8150. one or more of QX-1250 aminosilane oligomer, KRN8025, and Shin-Etsu 1146 aminosilane oligomer; The amount of the aminosilane oligomer added in S4 is 0.5-5.0wt% of the mass of the silica sol; The concentration of the silica sol in S4 is 30-40wt%, and the particle size is 10-30nm.

8. The method of claim 1, wherein, The Cr-containing compound in S5 is chromium oxide and / or a chromate; And / or, the Pd-containing compound in S5 is a water-soluble palladium salt; And / or, the mass ratio of the modified carrier to the aqueous solution in S5 is 1:(0.83-0.90); And / or, the drying temperature in S5 is 100-120℃, and the drying time is 4-12h; And / or, the calcining temperature in S5 is 450-600℃, and the calcining time is 2-8h.

9. The preparation method according to claim 8, characterized in that, The Cr-containing compound in S5 is one or more of CrO3, sodium chromate, and sodium dichromate. And / or, the Pd-containing compound in S5 is one or more of palladium chloride, palladium nitrate, and palladium chloride tetraammine; The concentration of Cr in the aqueous solution of the Cr- and Pd-containing compound in S5 is 0.6-3.0 wt%, and the concentration of Pd is 0.05-0.3 wt%.

10. A catalyst for dehydrogenation of 1,4-butanediol to γ-butyrolactone, which is prepared by the production method described in any one of claims 1 to 9, characterized by, The catalyst comprises the following components, with the total mass of the catalyst being 100 wt%:

11. Use of a dehydrogenation catalyst, which catalyst is a catalyst produced by the production process according to any one of claims 1 to 9 or a catalyst according to claim 10, characterized in that The catalyst is used in the reaction of 1,4-butanediol dehydrogenation to prepare gamma-butyrolactone.

12. Use according to claim 11, characterized in that, The catalyst is used in the reaction of 1,4-butanediol dehydrogenation to prepare gamma-butyrolactone under a reaction pressure of 0.3-0.5 atm.

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