Cu-based catalyst for preparing 1, 2-pentanediol and preparation process of 1, 2-pentanediol

Abstract

The invention relates to the technical field of catalysts, and particularly discloses a Cu-based catalyst for preparing 1, 2-pentanediol and a preparation process of the 1, 2-pentanediol. The Cu-based catalyst used for preparing 1, 2-pentanediol comprises 6-72% of a copper salt, 20-70% of a carrier, 4-12% of a transition metal oxide and 4-12% of a polymeric nitrogen-containing organic ligand, and the polymeric nitrogen-containing organic ligand is polypyrrole or polyaniline. The preparation process of the 1, 2-pentanediol comprises the following steps: mixing furfural, isopropanol and a Cu-based catalyst for preparing the 1, 2-pentanediol, adding the mixture into a high-pressure reaction kettle, and reacting for 10-14 hours in a hydrogen atmosphere of 2.8-3.2 MPa and at the temperature of 145-155 DEG C under continuous stirring to obtain the 1, 2-pentanediol. According to the Cu-based catalyst, the combination effect between the carrier and Cu can be enhanced, so that active Cu loaded on the carrier is more stable in the reaction process, and the catalytic performance of the Cu-based catalyst is improved.

Description

Technical Field

[0001] The invention relates to the technical field of catalysts, and in particular to a Cu-based catalyst for preparing 1,2-pentanediol and a preparation process of 1,2-pentanediol. Background Art

[0002] As an important organic intermediate, 1,2-pentanediol has been widely used in the synthesis of the fungicide propiconazole, high-end skin care products, polyester fibers, surfactants, medicines and other fields. In particular, it has an excellent performance in improving the water resistance of sunscreen products, making it an indispensable raw material in the cosmetics industry.

[0003] At present, the preparation method of 1,2-pentanediol often faces the problems of high raw material cost, complicated production process and serious equipment corrosion. These problems not only limit the large-scale production of 1,2-pentanediol, but also push up its market price and restrict the development of related downstream industries. Under such background, it is particularly important to develop an efficient, low-cost and environmentally friendly preparation process of 1,2-pentanediol.

[0004] In the related art, a method for preparing 1,2-pentanediol by liquid phase selective hydrogenolysis of furfuryl alcohol is disclosed, which is characterized in that the supported Cu-based catalyst uses Cu as the active component, the carrier is SiO2, Al2O3 or a molecular sieve, and the auxiliary agent is one or more of Mg, Ba, Co, Ni, Zn, Mn, Y, La, Ce, Sm, Ga, and B; the content of the active component Cu in the catalyst is 5-85wt%, and the content of the auxiliary oxide is 0-15wt%; the catalyst is used for the hydrogenolysis reaction of furfuryl alcohol to prepare 1,2-pentanediol, and the reaction conditions are a reaction temperature of 130-180°C and a reaction pressure of 4-10Mpa, and a reaction time of 1-12h; the furfuryl alcohol is furfuryl alcohol or an aqueous solution or a methanol solution of furfuryl alcohol; the content of furfuryl alcohol in the aqueous solution or the methanol solution of furfuryl alcohol is not less than 20wt%; the weight ratio of the active component of the catalyst to the raw material furfuryl alcohol is 1:100-1:10.

[0005] Cu-based catalyst is the core of this method, and its unique catalytic performance is the key to the success of the preparation method. Since factors such as the roughness of the carrier surface, pore structure and specific surface area will affect the binding force between the carrier and Cu, if the interaction between the carrier and Cu in the above-mentioned Cu-based catalyst is not strong enough, Cu may easily fall off from the carrier during the reaction, which will not only reduce the effective active components of the catalyst, but also may pollute the reaction system. Therefore, how to enhance the binding effect between the carrier and Cu is a key issue that needs to be solved when improving the catalytic performance of Cu-based catalysts. Summary of the invention

[0006] In order to improve the catalytic performance of Cu-based catalysts, the present application provides a Cu-based catalyst for preparing 1,2-pentanediol and a preparation process of 1,2-pentanediol.

[0007] In a first aspect, the present application provides a Cu-based catalyst for preparing 1,2-pentanediol, using the following technical solution:

[0008] A Cu-based catalyst for preparing 1,2-pentanediol comprises the following raw materials in percentage by mass: 6-72% of copper salt, 20-70% of carrier, 4-12% of transition metal oxide and 4-12% of polymeric nitrogen-containing organic ligand, wherein the polymeric nitrogen-containing organic ligand is polypyrrole or polyaniline.

[0009] By adopting the above technical scheme, copper salt provides active Cu, polypyrrole or polyaniline can form a stable ligand with active Cu through a coordination bond, and form a uniform ligand coating on the surface of the carrier, and can form a stable complex with transition metal ions, so that active Cu, carrier and transition metal oxide are closely connected together, so that active Cu is fixed on the surface of the carrier, reducing the possibility of falling off. Moreover, transition metal oxide can form a bridging effect between active Cu and the carrier, further enhancing the binding force between active Cu and the carrier. Therefore, the Cu-based catalyst of the present application can enhance the bonding effect between the carrier and Cu, so that the active Cu loaded on the carrier is more stable during the reaction, thereby improving the catalytic performance of the Cu-based catalyst.

[0010] In a specific embodiment, the transition metal oxide is ZrO2 or TiO2.

[0011] By adopting the above technical scheme, both ZrO2 and TiO2 can form a strong interaction with active Cu. Moreover, ZrO2 and TiO2 can provide abundant active sites, promote the adsorption and activation of reactants, help to reduce the activation energy of the reaction, and increase the reaction rate, thereby achieving a higher yield. ZrO2 and TiO2 also have good anti-poisoning properties, can resist the poisoning effect of impurities or poisons in the raw materials on the catalyst, and help to extend the service life of the catalyst. Therefore, the present application adopts ZrO2 or TiO2 as a transition metal oxide, which can improve the catalytic performance, stability and anti-poisoning ability of the Cu-based catalyst for preparing 1,2-pentanediol, and help to efficiently and sustainably produce 1,2-pentanediol.

[0012] In a specific embodiment, the carrier is a SiO2 / molecular sieve composite, which includes the following raw materials in parts by weight: 10-15 parts of SiO2 sol, 10-15 parts of water, 15-20 parts of silane, 0.5-1 parts of template, 0.5-1.5 parts of catalyst, and 0.5-1 parts of gelling agent.

[0013] By adopting the above technical solution, the template can occupy a certain space in the carrier. After being removed during the preparation process, pores will be left. These pores not only increase the specific surface area of ​​the carrier, but also provide more contact points and transmission channels for the reactants. Moreover, the composite of SiO2 and molecular sieve can further enhance the structural stability of the carrier, so that it can maintain a high specific surface area and pore structure without being destroyed during the catalytic reaction. Therefore, compared with SiO2 carriers or molecular sieve carriers, SiO2 / molecular sieve composite carriers have higher specific surface area and richer pore structure, which enhances the contact area between the catalyst and the reactants and can significantly improve the catalytic activity and reaction efficiency.

[0014] In a specific embodiment, the method for preparing the SiO2 / molecular sieve composite comprises the following steps: uniformly mixing silane, a template and water to obtain a mixed solution;

[0015] The mixed solution is transferred to a high-pressure reactor, reacted at 100-120° C. for 10-14 hours, and cooled naturally to obtain a molecular sieve precursor solution;

[0016] Adding SiO2 sol, catalyst and gelling agent into molecular sieve precursor solution to obtain gel system, and drying to obtain composite carrier precursor;

[0017] The composite carrier precursor is calcined, naturally cooled, and ground to obtain a SiO2 / molecular sieve composite.

[0018] By adopting the above technical solution, through the gradual mixing and reaction steps, it is helpful to evenly distribute SiO2 and molecular sieve in the composite, thereby helping to improve the overall stability of the composite, so that it can maintain the integrity of the structure during the catalytic reaction. By adopting the above temperature and reaction time, the obtained SiO2 / molecular sieve composite has a more excellent catalytic effect, which helps to improve the yield of 1,2-pentanediol.

[0019] In a specific embodiment, the template agent is hexadecyltrimethylammonium bromide.

[0020] By adopting the above technical solution, hexadecyl trimethyl ammonium bromide can self-assemble in the solution to form a specific structure. In the preparation process of SiO2 / molecular sieve composite, hexadecyl trimethyl ammonium bromide can guide silane and molecular sieve precursor to form an ordered pore structure, thereby increasing the specific surface area and pore volume of the composite. Due to the steric hindrance effect of its long-chain alkyl group, it can also prevent the aggregation and loss of active components, thereby improving the stability and service life of the SiO2 / molecular sieve composite.

[0021] In a specific embodiment, the catalyst is a Lewis acid-base catalyst.

[0022] By adopting the above technical solution, the Lewis acid-base catalyst can provide empty orbitals or lone pairs of electrons to form coordination bonds with reactants, thereby reducing the reaction activation energy and accelerating the reaction rate.

[0023] In a specific embodiment, the silane is tetraethyl orthosilicate.

[0024] By adopting the above technical solution, ethyl orthosilicate shows good stability during the hydrolysis process and can form a uniform network structure. This structure helps to improve the mechanical strength and stability of the catalyst and extend its service life. Ethyl orthosilicate has good compatibility with hexadecyltrimethylammonium bromide, Lewis acid-base catalysts, etc., and can form a uniform mixture during the preparation process to ensure uniform dispersion of the catalyst components.

[0025] In a specific embodiment, the composite carrier precursor is calcined at 500-600° C. for 4-6 hours to obtain a SiO 2 / molecular sieve composite.

[0026] By adopting the above technical solution, at the above temperature and time, the prepared SiO2 / molecular sieve can further improve the catalytic effect of the Cu-based catalyst. This may be because, at the above temperature and time, the pore size and pore distribution of the composite are improved, thereby improving the mass transfer performance of the Cu-based catalyst and improving the diffusion efficiency of reactants and products.

[0027] In a second aspect, the present application provides a process for preparing 1,2-pentanediol, using the following technical solution:

[0028] A process for preparing 1,2-pentanediol comprises the following steps:

[0029] Add copper salt, carrier, transition metal oxide, polymeric nitrogen-containing organic ligand into water, mix well, add into autoclave, keep warm at 100-110°C for 1.8-2h, stop heating, cool naturally, filter, wash, dry to obtain semi-finished product. Roast the semi-finished product at 400-420°C for 2.6-3.4h, cool naturally, grind, sieve to obtain 80-100 mesh solid powder, let the 80-100 mesh solid powder stand at 300-320°C in hydrogen atmosphere for 3.8-4.2h to obtain Cu-based catalyst for preparing 1,2-pentanediol;

[0030] Furfural, isopropanol and a Cu-based catalyst for preparing 1,2-pentanediol are mixed and added into a high-pressure reactor. The mixture is reacted for 10-14 hours in a hydrogen atmosphere of 2.8-3.2 MPa, 145-155° C. and under continuous stirring to obtain 1,2-pentanediol.

[0031] By adopting the above technical scheme, under the action of the above Cu-based catalyst and specific temperature and pressure, furfural and isopropanol can be efficiently converted into 1,2-pentanediol, the yield of 1,2-pentanediol is high, and the utilization rate of raw materials is improved.

[0032] In a specific embodiment, the mass ratio of furfural, isopropanol and the Cu-based catalyst for preparing 1,2-pentanediol is (15-85):(15-85):1.

[0033] In summary, this application has the following beneficial effects:

[0034] 1. The Cu-based catalyst of the present application can enhance the bonding effect between the carrier and Cu, making the active Cu loaded on the carrier more stable during the reaction, thereby improving the catalytic performance of the Cu-based catalyst.

[0035] 2. In the present application, SiO2 / molecular sieve composites are preferably used, which have a higher specific surface area and a richer pore structure, enhance the contact area between the catalyst and the reactants, and can significantly improve the catalytic activity and reaction efficiency.

[0036] 3. The process of the present application has a high yield of 1,2-pentanediol, thereby improving the utilization rate of raw materials. DETAILED DESCRIPTION

[0037] The present application is further described in detail below in conjunction with embodiments and comparative examples.

[0038] Example

[0039] Example 1

[0040] This embodiment provides a Cu-based catalyst for preparing 1,2-pentanediol, including the following raw materials: 40 g of copper nitrate, 45 g of SiO2, 7.5 g of ZrO2 and 7.5 g of polypyrrole (CAS No.: 30604-81-0).

[0041] A process for preparing 1,2-pentanediol comprises the following steps:

[0042] Copper nitrate, SiO2, ZrO2, and polypyrrole are added to water, stirred and shaken evenly, then added to a high-pressure reactor, sealed, stirred and heated to 100°C, stopped stirring, kept warm for 2 hours, stopped heating, cooled to room temperature naturally, and then filtered, the filtered solid was washed alternately with distilled water and anhydrous ethanol for 3 times, and then dried at 120°C for 12 hours to obtain a semi-finished product. The semi-finished product is placed in a muffle furnace, heated to 400°C, kept warm for 3.4 hours, stopped calcining, cooled to room temperature naturally, ground, sieved, and the sieved 80-100 mesh solid powder was left to stand at 300°C in a hydrogen atmosphere for 4.2 hours to obtain a Cu-based catalyst for preparing 1,2-pentanediol.

[0043] Furfural, isopropanol and a Cu-based catalyst for preparing 1,2-pentanediol were mixed in a weight ratio of 15:85:1, added into a high-pressure reactor, and reacted for 14 hours at a hydrogen atmosphere of 2.8 MPa, 155° C. and continuous stirring at a stirring speed of 500 r / min to obtain 1,2-pentanediol.

[0044] Example 2

[0045] The only difference between this embodiment and embodiment 1 is that the Cu-based catalyst used to prepare 1,2-pentanediol includes the following raw materials: 6 g of copper nitrate, 70 g of SiO2, 12 g of ZrO2 and 12 g of polypyrrole.

[0046] Example 3

[0047] The only difference between this embodiment and embodiment 1 is that the Cu-based catalyst used to prepare 1,2-pentanediol includes the following raw materials: 72 g of copper nitrate, 20 g of SiO2, 4 g of ZrO2 and 4 g of polypyrrole.

[0048] Example 4

[0049] The only difference between this embodiment and embodiment 1 is that an equal amount of polyaniline is used to replace polypyrrole.

[0050] Example 5

[0051] The only difference between this embodiment and embodiment 1 is that an equal amount of TiO2 is used to replace ZrO2.

[0052] Example 6

[0053] The only difference between this embodiment and embodiment 1 is that ZrO2 is replaced by an equal amount of NiO.

[0054] Example 7

[0055] The only difference between this embodiment and embodiment 1 is that ZrO2 is replaced by an equal amount of ZnO.

[0056] Example 8

[0057] The only difference between this embodiment and embodiment 1 is that SiO2 is replaced by an equal amount of molecular sieve.

[0058] Example 9

[0059] The difference between this embodiment and embodiment 1 is that SiO2 is replaced by an equal amount of SiO2 / molecular sieve composite. The SiO2 / molecular sieve composite includes the following raw materials: 12.5 g of SiO2 sol (model: LUDOX HS-30), 12.5 g of water, 17.5 g of ethyl orthosilicate, 0.75 g of hexadecyltrimethylammonium bromide, 1 g of Lewis acid-base catalyst, and 0.75 g of ammonia water with a mass concentration of 25%.

[0060] The preparation method of SiO2 / molecular sieve composite comprises the following steps:

[0061] Tetraethyl orthosilicate, a template agent and water are mixed and stirred until uniform to obtain a mixed solution.

[0062] The mixed solution was transferred to a high-pressure reactor, heated to 110° C., kept warm for 12 hours, and then naturally cooled to room temperature to obtain a molecular sieve precursor solution.

[0063] Add SiO2 sol, Lewis acid-base catalyst and ammonia water into the molecular sieve precursor solution, stir evenly to obtain a gel system, dry the gel system to obtain a composite carrier precursor.

[0064] The composite carrier precursor was placed in a muffle furnace, heated to 550°C, kept warm and calcined for 5 hours, then naturally cooled and ground to obtain a SiO2 / molecular sieve composite.

[0065] Example 10

[0066] The only difference between this embodiment and embodiment 9 is that the SiO2 / molecular sieve composite includes the following raw materials: 10g SiO2 sol (model: LUDOX HS-30), 15g water, 15g tetraethyl orthosilicate, 0.5g hexadecyltrimethylammonium bromide, 0.5g Lewis acid-base catalyst, and 0.5g ammonia water with a mass concentration of 25%.

[0067] Embodiment 11

[0068] The only difference between this embodiment and Embodiment 9 is that the SiO2 / molecular sieve composite includes the following raw materials: 15 g SiO2 sol (model: LUDOX HS-30), 10 g water, 10 g tetraethyl orthosilicate, 1 g hexadecyltrimethylammonium bromide, 1.5 g Lewis acid-base catalyst, and 1 g ammonia water with a mass concentration of 25%.

[0069] Example 12

[0070] The only difference between this embodiment and embodiment 9 is that an equal amount of triethanolamine is used to replace hexadecyltrimethylammonium bromide.

[0071] Embodiment 13

[0072] The only difference between this example and Example 9 is that the Lewis acid-base catalyst is replaced by an equal amount of bismuth neodecanoate catalyst (LK-5).

[0073] Embodiment 14

[0074] The only difference between this embodiment and embodiment 9 is that an equal amount of tridecafluorooctyltrimethoxysilane is used to replace ethyl orthosilicate.

[0075] Embodiment 15

[0076] The only difference between this embodiment and embodiment 9 is that an equal amount of hexadecyltrimethoxysilane is used to replace ethyl orthosilicate.

[0077] Example 16

[0078] The only difference between this embodiment and embodiment 9 is that in the method for preparing the SiO2 / molecular sieve complex: the mixed solution is transferred to a high-pressure reactor, heated to 100°C, kept warm for 14 hours, and then naturally cooled to room temperature to obtain a molecular sieve precursor solution.

[0079] Add SiO2 sol, Lewis acid-base catalyst and ammonia water into the molecular sieve precursor solution, stir evenly to obtain a gel system, dry the gel system to obtain a composite carrier precursor.

[0080] The composite carrier precursor was placed in a muffle furnace, heated to 500°C, kept warm and calcined for 6 hours, then naturally cooled and ground to obtain a SiO2 / molecular sieve composite.

[0081] Embodiment 17

[0082] The only difference between this embodiment and embodiment 9 is that in the method for preparing the SiO2 / molecular sieve complex: the mixed solution is transferred to a high-pressure reactor, heated to 120°C, kept warm for 10 hours, and then naturally cooled to room temperature to obtain a molecular sieve precursor solution.

[0083] Add SiO2 sol, Lewis acid-base catalyst and ammonia water into the molecular sieve precursor solution, stir evenly to obtain a gel system, dry the gel system to obtain a composite carrier precursor.

[0084] The composite carrier precursor was placed in a muffle furnace, heated to 600°C, kept warm and calcined for 4 hours, naturally cooled and ground to obtain a SiO2 / molecular sieve composite.

[0085] Embodiment 18

[0086] The difference between this embodiment and embodiment 1 is that in the preparation process of 1,2-pentanediol:

[0087] Copper nitrate, SiO2, ZrO2, and polypyrrole are added to water, stirred and shaken evenly, then added to a high-pressure reactor, sealed, stirred and heated to 110°C, stopped stirring, kept warm for 1.8 hours, stopped heating, cooled to room temperature naturally, and then filtered, the filtered solid was washed alternately with distilled water and anhydrous ethanol for 3 times, and then dried at 120°C for 12 hours to obtain a semi-finished product. The semi-finished product was placed in a muffle furnace, heated to 420°C, kept warm for 2.6 hours, stopped calcining, cooled to room temperature naturally, ground, sieved, and the sieved 80-100 mesh solid powder was left to stand at 320°C in a hydrogen atmosphere for 3.8 hours to obtain a Cu-based catalyst for the preparation of 1,2-pentanediol.

[0088] Embodiment 19

[0089] The difference between this embodiment and embodiment 1 is that in the preparation process of 1,2-pentanediol:

[0090] Furfural, isopropanol, and a Cu-based catalyst for preparing 1,2-pentanediol were mixed in a weight ratio of 55:45:1.

[0091] Embodiment 20

[0092] The difference between this embodiment and embodiment 1 is that in the preparation process of 1,2-pentanediol:

[0093] Furfural, isopropanol, and a Cu-based catalyst for preparing 1,2-pentanediol were mixed in a weight ratio of 85:15:1.

[0094] Comparative Example

[0095] Comparative Example 1

[0096] The only difference between this comparative example and Example 1 is that an equal amount of tetrahydropyrrole is used to replace polypyrrole.

[0097] Comparative Example 2

[0098] The only difference between this comparative example and Example 1 is that polypyrrole is replaced by an equal amount of ethylenediamine.

[0099] Comparative Example 3

[0100] The only difference between this comparative example and Example 1 is that an equal amount of SiO2 is used to replace polypyrrole.

[0101] Comparative Example 4

[0102] The only difference between this comparative example and Example 1 is that an equal amount of SiO2 is used to replace ZrO2.

[0103] Comparative Example 5

[0104] The difference between this comparative example and Example 1 is that in the preparation process of 1,2-pentanediol:

[0105] The Cu-based catalyst used in the preparation of 1,2-pentanediol was replaced with an equal amount of copper chromite.

[0106] Comparative Example 6

[0107] The difference between this comparative example and Example 1 is that in the preparation process of 1,2-pentanediol:

[0108] Furfural, isopropanol, and a Cu-based catalyst for preparing 1,2-pentanediol were mixed in a weight ratio of 90:10:1.

[0109] Comparative Example 7

[0110] The difference between this comparative example and Example 1 is that in the preparation process of 1,2-pentanediol:

[0111] Furfural, isopropanol, and a Cu-based catalyst for preparing 1,2-pentanediol were mixed in a weight ratio of 10:90:1.

[0112] Performance testing

[0113] With respect to the preparation processes of 1,2-pentanediol of Examples 1-20 and Comparative Examples 1-7, the yield of 1,2-pentanediol and the selectivity for 1,2-pentanediol of each Example and Comparative Example were calculated. The results are shown in Table 1.

[0114] Table 1

[0115]

[0116]

[0117] Combining Example 1 and Comparative Examples 1-4 and Table 1, it can be seen that compared with Example 1, the yield and selectivity of 1,2-pentanediol in Comparative Examples 1-4 are significantly reduced, which shows that the use of the Cu-based catalyst of Example 1 helps to improve the catalytic effect and selectivity of the Cu-based catalyst and improve the yield of the 1,2-pentanediol preparation process.

[0118] It can be seen from Examples 1-7 and Table 1 that Examples 1-7 all have higher 1,2-pentanediol yield and selectivity, but compared with other Examples, the values ​​of Examples 6 and 7 are smaller. This shows that the raw material ratios of Examples 1-7 can improve the catalytic effect and selectivity of the Cu-based catalyst, and the effect of using TiO2 or ZrO2 is better.

[0119] It can be seen from Examples 1, 8-17 and Table 1 that Examples 1 and 8-17 all have higher 1,2-pentanediol yield and selectivity, but compared with Examples 1 and 8, the values ​​of Examples 9-11 and 16-17 are larger, and compared with Example 9, the values ​​of Examples 12-15 are smaller, which shows that the SiO2 / molecular sieve composite prepared by the raw material ratio and process conditions of Examples 9-11 and 16-17 can help to further improve the catalytic effect and selectivity of the Cu-based catalyst.

[0120] Combining Examples 1, 18-20 and Comparative Examples 6-7 and Table 1, it can be seen that Examples 1 and 18-20 all have higher 1,2-pentanediol yield and selectivity, but the 1,2-pentanediol yield and selectivity of Comparative Example 6 are both lower than those of Example 20, and the 1,2-pentanediol yield and selectivity of Comparative Example 7 are both lower than those of Example 1, which indicates that the raw material ratios of Examples 1 and 18-20 are helpful to further improve the 1,2-pentanediol yield and selectivity.

[0121] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. A Cu-based catalyst for preparing 1,2-pentanediol, characterized in that: The invention comprises the following raw materials in percentage by mass: 6-72% of copper salt, 20-70% of carrier, 4-12% of transition metal oxide and 4-12% of polymeric nitrogen-containing organic ligand, wherein the polymeric nitrogen-containing organic ligand is polypyrrole or polyaniline.

2. A Cu-based catalyst for preparing 1,2-pentanediol according to claim 1, characterized in that: The transition metal oxide is ZrO2 or TiO2.

3. A Cu-based catalyst for preparing 1,2-pentanediol according to claim 1, characterized in that: The carrier is a SiO2 / molecular sieve complex, which includes the following raw materials in parts by weight: 10-15 parts of SiO2 sol, 10-15 parts of water, 15-20 parts of silane, 0.5-1 part of template, 0.5-1.5 parts of catalyst, and 0.5-1 part of gelling agent.

4. A Cu-based catalyst for preparing 1,2-pentanediol according to claim 3, characterized in that: The method for preparing the SiO2 / molecular sieve composite comprises the following steps: Mixing silane, template and water uniformly to obtain a mixed solution; The mixed solution is transferred to a high-pressure reactor, reacted at 100-120° C. for 10-14 hours, and cooled naturally to obtain a molecular sieve precursor solution; Adding SiO2 sol, catalyst and gelling agent into molecular sieve precursor solution to obtain gel system, and drying to obtain composite carrier precursor; The composite carrier precursor is calcined, naturally cooled, and ground to obtain a SiO2 / molecular sieve composite.

5. A Cu-based catalyst for preparing 1,2-pentanediol according to claim 4, characterized in that: The template agent is hexadecyltrimethylammonium bromide.

6. A Cu-based catalyst for preparing 1,2-pentanediol according to claim 5, characterized in that: The catalyst is a Lewis acid-base catalyst.

7. A Cu-based catalyst for preparing 1,2-pentanediol according to claim 6, characterized in that: The silane is ethyl orthosilicate.

8. A Cu-based catalyst for preparing 1,2-pentanediol according to claim 4, characterized in that: The composite carrier precursor is calcined at 500-600° C. for 4-6 hours to obtain a SiO2 / molecular sieve composite.

9. A process for preparing 1,2-pentanediol using the Cu-based catalyst for preparing 1,2-pentanediol according to any one of claims 1 to 8, characterized in that: The steps include: Add copper salt, carrier, transition metal oxide, polymeric nitrogen-containing organic ligand into water, mix well, add into autoclave, keep warm at 100-110°C for 1.8-2h, stop heating, cool naturally, filter, wash, dry to obtain semi-finished product. Roast the semi-finished product at 400-420°C for 2.6-3.4h, cool naturally, grind, sieve to obtain 80-100 mesh solid powder, let the 80-100 mesh solid powder stand at 300-320°C in hydrogen atmosphere for 3.8-4.2h to obtain Cu-based catalyst for preparing 1,2-pentanediol; Furfural, isopropanol and a Cu-based catalyst for preparing 1,2-pentanediol are mixed and added into a high-pressure reactor. The mixture is reacted for 10-14 hours in a hydrogen atmosphere of 2.8-3.2 MPa, 145-155° C. and under continuous stirring to obtain 1,2-pentanediol.

10. A process for preparing 1,2-pentanediol according to claim 9, characterized in that: The mass ratio of furfural, isopropanol and the Cu-based catalyst for preparing 1,2-pentanediol is (15-85):(15-85):1.

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