A catalyst for preparing 1,2-pentanediol by hydrolyzing furfuryl alcohol and a method for preparing the same, and a method for preparing 1,2-pentanediol

Abstract

The application discloses a catalyst for preparing 1,2-pentanediol by furoic alcohol hydrogenation and a preparation method thereof, and a method for preparing 1,2-pentanediol. The catalyst uses copper oxide as an active metal and a carrier modified by cobalt disulfide to improve the reaction activity and selectivity of the catalyst. Furoic alcohol is reacted under the catalyst and hydrogen to generate 1,2-pentanediol. Compared with an existing process, the method has the advantages of simple reaction flow, mild reaction condition, high 1,2-pentanediol selectivity and simple subsequent separation.

Description

TECHNICAL FIELD

[0001] The present application relates to a method for preparing a catalyst for producing 1,2-pentanediol by hydrogenation of furfuryl alcohol, and a method for producing 1,2-pentanediol by hydrogenation of furfuryl alcohol using the catalyst. BACKGROUND

[0002] 1,2-pentanediol is a linear diol containing a double hydroxyl group and a relatively long chain alkyl group. 1,2-pentanediol is mainly used as a key raw material for the fungicide propiconazole, and is also a raw material for polyester fibers, surfactants, and pharmaceuticals, etc. 1,2-pentanediol is also widely used in products such as baby products, bath products, cosmetics, cleaning products, skin care products, and hair care products, etc. due to its excellent moisturizing and antibacterial properties.

[0003] The current main production process for 1,2-pentanediol is the pentene method. Pentene is used to produce 1,2-pentanediol through processes such as epoxidation, esterification, and hydrolysis with peroxide. This process has the disadvantages of limited source of pentene raw material, complex process, high safety risk due to the use of peroxide in the production process, and high corrosion of wastewater, which seriously restricts the development of 1,2-pentanediol. Therefore, it is of great significance and good prospect to develop a new technical route with high production efficiency and low environmental pollution using raw materials with wide sources and low prices.

[0004] Furfuryl alcohol is a product obtained by hydrogenation of biomass furfural, and furfural is obtained by hydrolysis of common agricultural and sideline products such as corn cob, which is easy to obtain and has a significant price advantage compared with other raw materials for producing 1,2-pentanediol. The key to the catalytic hydrogenation method of furfuryl alcohol lies in the development of a suitable catalyst.

[0005] Patent CN201911107004.9 discloses a method for producing 1,2-pentanediol. In this method, furfuryl alcohol is selectively hydrogenated to produce 1,2-pentanediol under the catalytic action of a noble metal catalyst supported on a composite carrier. This process uses a noble metal catalyst, which has a high cost. The yield of 1,2-pentanediol in the product is only about 40%, and the yield of low-value byproduct tetrahydrofurfuryl alcohol is more than 50%.

[0006] Patent CN201310361013.7 discloses a method for producing 1,2-pentanediol by selectively hydrogenolysis of furfuryl alcohol in liquid phase. In this method, furfuryl alcohol is selectively hydrogenated to produce 1,2-pentanediol under the catalytic action of a copper catalyst. The operation pressure of this process is limited by the fact that the reaction pressure is as high as 8 MPa, which is not mild enough. In addition, this process has the disadvantages of low conversion rate of furfuryl alcohol and low yield of 1,2-pentanediol.

[0007] Patent CN201320723632.6 discloses a production method for preparing 1,2-pentanediol by hydrogenolysis of furfuryl alcohol, which uses a Pt or Ru catalyst. The process uses a noble metal catalyst, and the activity of furan ring opening is not high. The yield of 1,2-pentanediol in the product is only about 34%, the catalyst cost is high, and the yield of 1,2-pentanediol is low.

[0008] Patent CN111715264B discloses a method for preparing 1,5-pentanediol by catalytic hydrogenation of tetrahydrofurfuryl alcohol. Copper oxide is used as an active component, and one or more of iron, cobalt, nickel, zinc, chromium, and vanadium is used as a modified metal. Titanium trisulfide is used as a cocatalyst. The composite components are loaded on a molybdenum carbide carrier, and the composite components are applied to the preparation of 1,5-pentanediol from tetrahydrofurfuryl alcohol. The patent needs to use iron and other non-noble metals to modify the copper catalyst to improve the anti-sintering performance of the copper catalyst. The use of molybdenum carbide improves the stability and activity of the copper catalyst. Titanium trisulfide is used as a cocatalyst to improve the overall electronic transfer performance of the catalyst. The patent uses tetrahydrofurfuryl alcohol as a raw material to prepare 1,5-pentanediol by catalytic hydrogenation. The yield of 1,2-pentanediol is not mentioned.

[0009] Patent CN109896921B provides a method for preparing 1,5-pentanediol by catalytic hydrogenation of tetrahydrofurfuryl alcohol using a molybdenum sulfide-containing catalyst. The carrier of the catalyst is cerium dioxide, and the catalytic hydrogenation active metal is platinum. The platinum loading is 0.5-5wt%, and the MoS2 loading is 10-40wt%. Using the catalyst, the main product of tetrahydrofurfuryl alcohol hydrogenation is 1,5-pentanediol, and the by-products are n-pentanol, tetrahydropyran, 2-methyltetrahydropyran, and n-pentane. No 1,2-pentanediol is generated.

[0010] The current development of catalysts for the hydrogenolysis of furfuryl alcohol to 1,2-pentanediol has the following problems: non-noble metal catalyst Cu requires harsh reaction pressure, generally requiring a pressure of 8Mpa or higher, and has the disadvantages of low 1,2-pentanediol yield and high low-value tetrahydrofurfuryl alcohol yield; noble metal catalyst Pt has the problems of low catalytic activity for furan ring opening, low pentanediol yield, and short catalyst service life. SUMMARY

[0011] The purpose of the present application is to provide a catalyst for preparing 1,2-pentanediol by hydrogenation of furfuryl alcohol, and a process for producing 1,2-pentanediol using the catalyst. The catalyst is inexpensive, the reaction conditions are mild, the reaction process is simple, the yield of 1,2-pentanediol is high, and the yield of high-value products is high. Compared with the existing process, the method of the present application has the advantages of simple reaction process, mild reaction conditions, high 1,2-pentanediol selectivity, and simple subsequent separation.

[0012] To solve the above technical problems, the technical solution adopted by the present application is as follows:

[0013] A catalyst for preparing 1,2-pentanediol by hydrolyzing furfuryl alcohol, comprising an alumina and / or silica carrier, a copper oxide active component supported on the carrier, and a cobalt disulfide adjuvant.

[0014] A preparation method of the catalyst, comprising the following steps:

[0015] (1) adding ethylenediaminetetraacetic acid into a cobalt salt aqueous solution, and then adding sodium sulfide and sodium hydroxide for dissolution;

[0016] (2) adding the carrier into the product of step (1) for hydrothermal reaction, cooling, separation, washing, and drying to obtain a cobalt sulfide modified catalyst carrier;

[0017] (3) impregnating the product of step (2) in a copper salt aqueous solution, drying, molding, and calcining.

[0018] The cobalt salt is selected from one or more of cobalt sulfate, cobalt nitrate, cobalt acetate, and other water-soluble cobalt salts.

[0019] In step (1), the molar ratio of ethylenediaminetetraacetic acid to cobalt salt is 0.9-1.2:1, preferably 0.95-1.1:1.

[0020] In step (1), the molar ratio of sodium sulfide to cobalt salt is 2.0-2.6:1, preferably 2.0-2.2:1.

[0021] In step (1), the molar ratio of sodium hydroxide to cobalt salt is 0.9-1.2:1, preferably 0.95-1.1:1.

[0022] In the product of step (2), the mass ratio of cobalt disulfide to the carrier is 1-10%, preferably 3-5%.

[0023] In step (2), the temperature of the hydrothermal reaction is 120-160°C, preferably 135-145°C, and the reaction time is 10-24h, preferably 16-20h.

[0024] In step (2), the washing comprises sequentially using carbon disulfide, anhydrous ethanol, and distilled water.

[0025] In step (2), the drying temperature is 55-65°C, and the time is 3-5h.

[0026] In step (3), the copper salt is selected from one or more of copper sulfate, copper nitrate, and copper acetate.

[0027] In step (3), the impregnation temperature is room temperature, and the time is 6-12h.

[0028] In step (3) of the present application, the impregnated catalyst is oven dried at 50-120℃ for 6-12h.

[0029] In step (3) of the present application, the calcination temperature is 500-700℃ for 4-12h.

[0030] In the catalyst, the loading of copper oxide is 1-30wt% of the carrier mass, preferably 10-20wt%.

[0031] The catalyst of the present application is reduced by a mixture of nitrogen and hydrogen (hydrogen volume content 2-20%) at 200-450℃ for 4-10h, and has activity.

[0032] The reason why the catalyst of the present application has excellent catalytic performance is that the surface metal active site Cu 0 and CoSx species synergistically catalyze, the metal site Cu 0 adsorbs and activates hydrogen, Co in CoSx can adsorb active hydrogen, and the sulfur vacancy in CoSx can anchor the hydroxyl group in furfuryl alcohol to produce a slantwise adsorption, which promotes the hydrogenation of the C=C bond on the furan ring, while also weakening and breaking the furan C-O bond, thereby improving the selectivity of 1,2-pentanediol, and also producing a part of 1,5-pentanediol as a byproduct. CoS2 is a typical cubic structure, Co 2+ is surrounded by six S - around it to form an octahedral coordination, and S - and three Co 2+ around it form a tetrahedral coordination. The presence of Cu promotes the reduction of CoS2, Co 2+ is reduced to Co atoms or Co + , so that sulfur defect sites suitable for catalytic reaction are generated, which is conducive to the occurrence of catalytic reaction.

[0033] In the catalyst of the present application, when the molar ratio of CuO to CoS2 is 1-20:1, preferably 4-10:1, the defect content on the surface of the catalyst is relatively optimal, and the catalyst has a high content of Cu 0 and a preferred ability to activate hydrogen, and the catalyst exhibits excellent performance in reaction.

[0034] A method for preparing 1,2-pentanediol by hydrogenation of furfuryl alcohol, comprising the following steps: in a hydrogenation reactor, furfuryl alcohol is reacted in the presence of the catalyst and hydrogen to produce 1,2-pentanediol.

[0035] The hydrogenation reactor of the present application is a kettle type reactor, a fixed bed, or a loop reactor, preferably a fixed bed reactor.

[0036] The hydrogenation can be directly reacted without solvent, or a solvent can be used, and the solvent is preferably an alcohol or an ether with carbon number of 1-4, and more preferably methanol and / or THF.

[0037] The hydrogenation reaction temperature is 100-200℃, and preferably 130-150℃.

[0038] The hydrogenation reaction pressure is 1-20Mpa, and preferably 2-6Mpa.

[0039] In the hydrogenation reaction, the space velocity of furfuryl alcohol is 0.02-0.5h -1 , and preferably 0.06-0.2h -1 .

[0040] Compared with the prior art, the present application has the following beneficial effects:

[0041] 1) The non-noble metal copper oxide catalyst system is used, and the raw material cost of the catalyst is low;

[0042] 2) The cobalt disulfide is used as a cocatalyst to improve the reaction activity and selectivity of the catalyst;

[0043] 3) The process reaction flow is simple, the reaction conditions are mild, the selectivity of 1,2-pentanediol is high, the separation process is simple, the equipment investment and energy consumption can be saved, and the process is suitable for industrial production. DETAILED DESCRIPTION

[0044] The present application will be described in detail below through specific examples. The scope of the present application is not limited to the specific embodiment.

[0045] Preparation of cobalt sulfide and modification of carrier

[0046] Example 1

[0047] Into a 500ml autoclave, 300ml deionized water, 11.8g cobalt nitrate hexahydrate, 11.9g ethylenediaminetetraacetic acid, 6.5g sodium sulfide and 1.8g sodium hydroxide were sequentially added, and then stirred until dissolved. Under stirring, 100g inert alumina powder was added, and reacted at 140℃ for 16h. After hydrothermal reaction, the generated cobalt sulfide was fully mixed with the carrier. After natural cooling to room temperature, filtration, washing with carbon disulfide, anhydrous ethanol and distilled water in sequence, and then placed in an oven, dried at 60℃ for 4h, taken out and ground to prepare a cobalt sulfide modified catalyst carrier-1, and the content of cobalt sulfide was about 5wt% of the carrier.

[0048] Example 2

[0049] Into a 500ml autoclave, 300ml of deionized water, 7.1g of cobalt nitrate hexahydrate, and 7.1g of ethylenediaminetetraacetic acid were sequentially added, and then 4.2g of sodium sulfide and 1.0g of sodium hydroxide were added, and stirred until dissolved. While stirring, 100g of inert alumina powder was added, and reacted at 145°C for 18h. After the hydrothermal reaction, the generated cobalt sulfide was mixed with the carrier. After natural cooling to room temperature, the mixture was filtered, washed with carbon disulfide, anhydrous ethanol, and distilled water, and then dried in an oven at 60°C for 4h. After grinding, a cobalt sulfide-modified catalyst carrier-2 was prepared, and the cobalt sulfide content was about 3wt% of the carrier.

[0050] Example 3

[0051] Into a 500ml autoclave, 300ml of deionized water, 9.5g of cobalt nitrate hexahydrate, and 9.5g of ethylenediaminetetraacetic acid were sequentially added, and then 5.3g of sodium sulfide and 1.3g of sodium hydroxide were added, and stirred until dissolved. While stirring, 100g of inert alumina powder was added, and reacted at 135°C for 20h. After the hydrothermal reaction, the generated cobalt sulfide was mixed with the carrier. After natural cooling to room temperature, the mixture was filtered, washed with carbon disulfide, anhydrous ethanol, and distilled water, and then dried in an oven at 60°C for 4h. After grinding, a cobalt sulfide-modified catalyst carrier-3 was prepared, and the cobalt sulfide content was about 4wt% of the carrier.

[0052] Catalyst preparation

[0053] Example 4

[0054] The catalyst was prepared by the equivalent impregnation method.

[0055] Into a 500ml beaker, 100g of the carrier-1 obtained in Example 1 was placed, and 47.5g of copper nitrate dissolved in water was diluted to 100ml, and then the copper nitrate solution was added dropwise while stirring with a glass rod. After the dropwise addition was completed, the mixture was immersed at room temperature for 10h, and then dried in an oven at 100°C for 6h. After that, the mixture was extruded into a 2mm cylindrical catalyst, and then calcined at 550°C for 10h, thereby preparing a catalyst 1. The copper oxide loading amount of the catalyst was about 20% of the carrier, and the molar ratio of cobalt sulfide to copper oxide was about 1:6.5.

[0056] Example 5

[0057] Example 4

[0058] Example 6

[0059] Example 4

[0060] Comparative Example 1

[0061] Comparative Example 1

[0062] Comparative Example 2

[0063] Comparative Example 2

[0064] Comparative Example 3

[0065] Comparative Example 3

[0066] Catalyst Evaluation

[0067] Example 7

[0068] Example 7 -1hydrogen to furfuryl alcohol molar ratio 40: 1, continuously pumping 30wt% furfuryl alcohol in THF solution, sampling analysis, furfuryl alcohol conversion rate is greater than 99.9%, 1,2-pentanediol selectivity is 60.2%, 1,5-pentanediol selectivity is 20.3%, pentanol selectivity is 8.8%, tetrahydrofurfuryl alcohol selectivity is 4.5%, and the selectivity of other components is 6.2% in total.

[0069] Example 8

[0070] Take catalyst-2 described in Example 5 50ml, install in fixed bed reactor, the catalyst is reduced by nitrogen and hydrogen mixed gas (hydrogen volume content 10%) at 300°C for 6h before reaction evaluation, then reduce temperature for reaction evaluation. The reaction hot spot temperature is 140°C, the reaction pressure is 4MPa, the furfuryl alcohol space velocity is 0.1h -1 hydrogen to furfuryl alcohol molar ratio 40: 1, continuously pumping 30wt% furfuryl alcohol in THF solution, sampling analysis, furfuryl alcohol conversion rate is greater than 99.9%, 1,2-pentanediol selectivity is 60.2%, 1,5-pentanediol selectivity is 20.3%, pentanol selectivity is 8.8%, tetrahydrofurfuryl alcohol selectivity is 4.5%, and the selectivity of other components is 6.2% in total.

[0071] Example 9

[0072] Take catalyst-3 described in Example 6 50ml, install in fixed bed reactor, the catalyst is reduced by nitrogen and hydrogen mixed gas (hydrogen volume content 10%) at 300°C for 6h before reaction evaluation, then reduce temperature for reaction evaluation. The reaction hot spot temperature is 135°C, the reaction pressure is 2MPa, the furfuryl alcohol space velocity is 0.06h -1 hydrogen to furfuryl alcohol molar ratio 40: 1, continuously pumping 30wt% furfuryl alcohol in THF solution, sampling analysis, furfuryl alcohol conversion rate is greater than 99.9%, 1,2-pentanediol selectivity is 60.2%, 1,5-pentanediol selectivity is 20.3%, pentanol selectivity is 8.8%, tetrahydrofurfuryl alcohol selectivity is 4.5%, and the selectivity of other components is 6.2% in total.

[0073] Comparative Example 4

[0074] Except that the catalyst is replaced by the catalyst described in Comparative Example 1, other conditions are as in Example 7, furfuryl alcohol conversion rate is 99.5%, 1,2-pentanediol selectivity is 32.1%, 1,5-pentanediol selectivity is 10.4%, tetrahydrofurfuryl alcohol selectivity is 40.5%, pentanol selectivity is 4.5%, and the selectivity of other components is 12.5% in total.

[0075] Comparative Example 5

[0076] Example 9 except that the catalyst was replaced by the catalyst described in Comparative Example 2. The conversion of furfuryl alcohol was 99.6%, the selectivity of 1,2-pentanediol was 28.6%, the selectivity of 1,5-pentanediol was 11.3%, the selectivity of tetrahydrofurfuryl alcohol was 33.5%, the selectivity of pentanol was 7.5%, and the selectivity of other components was 19.1%.

[0077] Comparative Example 6

[0078] Example 8 except that the catalyst was replaced by the catalyst described in Comparative Example 3. The conversion of furfuryl alcohol was 99.7%, the selectivity of 1,2-pentanediol was 33.6%, the selectivity of 1,5-pentanediol was 12.5%, the selectivity of tetrahydrofurfuryl alcohol was 29.5%, the selectivity of pentanol was 12.4%, and the selectivity of other components was 12.0%.

[0079] Comparative Example 7

[0080] Example 7 except that the catalyst was replaced by the carrier described in Example 1 without adding active metal components. The conversion of furfuryl alcohol was 7.9%, the selectivity of 1,2-pentanediol was 8.9%, the selectivity of 1,5-pentanediol was 4.8%, the selectivity of tetrahydrofurfuryl alcohol was 74.5%, the selectivity of pentanol was 2.5%, and the selectivity of other components was 9.3%.

[0081] From the above examples, it can be seen that the present application is simple to operate and can greatly improve the yield of target products 1,2-pentanediol and high-value 1,5-pentanediol, and simplifies the separation process.

Claims

1. A catalyst for preparing 1,2-pentanediol by hydrogenation of furfuryl alcohol, comprising an alumina and / or silica carrier, a copper oxide active component supported on the carrier, and a cobalt disulfide promoter; a method for preparing the catalyst, comprising the following steps: (1) adding ethylenediaminetetraacetic acid to an aqueous cobalt salt solution, then adding sodium sulfide and sodium hydroxide, and dissolving; (2) adding the carrier to the product of step (1), and hydrothermally reacting, cooling, separating, washing, and drying to obtain a cobalt disulfide modified catalyst carrier; (3) impregnating the product of step (2) in an aqueous copper salt solution, drying, molding, and calcining. The loading of copper oxide is 1-30 wt% of the mass of the carrier. The loading of copper oxide is 10-20 wt% of the mass of the carrier. The molar ratio of copper oxide to cobalt disulfide is 1-20:

1.

2. The catalyst according to claim 1, characterized in that, The molar ratio of copper oxide to cobalt disulfide is 4-10:

1.

3. The catalyst of claim 1, wherein The cobalt salt is selected from one or more of cobalt sulfate, cobalt nitrate, and cobalt acetate.

4. The catalyst of claim 1, wherein In step (1), the molar ratio of ethylenediaminetetraacetic acid to cobalt salt is 0.9-1.2:1, and the molar ratio of sodium sulfide to cobalt salt is 2.0-2.6:

1.

5. The catalyst of claim 1, wherein In step (1), the molar ratio of ethylenediaminetetraacetic acid to cobalt salt is 0.95-1.1:1, and the molar ratio of sodium sulfide to cobalt salt is 2.0-2.2:

1.

6. The catalyst of claim 1, wherein In step (2), the temperature of the hydrothermal reaction is 120-160°C, and the reaction time is 10-24 h.

7. The catalyst of claim 1, wherein In step (2), the temperature of the hydrothermal reaction is 135-145°C, and the reaction time is 16-20 h.

8. The catalyst of claim 1, wherein The copper salt is selected from one or more of copper sulfate, copper nitrate, and copper acetate.

9. The catalyst of claim 1, wherein In step (3), the calcination temperature is 500-700°C, and the time is 4-12 h.

10. The catalyst of claim 1, wherein In a hydrogenation reactor, furfuryl alcohol is reacted in the presence of the catalyst of claim 1 and hydrogen to produce 1,2-pentanediol.

11. The method of claim 1, wherein, ​ 12. The method of claim 1, wherein, ​ 13. A process for the production of 1,2-pentanediol by the hydrogenation of furfuryl alcohol comprising the steps of: ​ 14. The method of claim 13, wherein, The hydrogenation reaction temperature is 100-200℃; the hydrogenation reaction pressure is 1-20Mpa; the furfuryl alcohol space velocity is 0.02-0.5h -1 .

15. The method of claim 13, wherein, The hydrogenation reaction temperature is 130-150℃; the hydrogenation reaction pressure is 2-6 Mpa; the furfuryl alcohol space velocity is 0.06-0.2 h -1 .