阅读说明：本技术 一种铜硅催化剂及其制备方法和应用 (Copper-silicon catalyst and preparation method and application thereof ) 是由 陈静 方伟国 刘海龙 于 2021-07-28 设计创作，主要内容包括：本发明涉及一种铜硅催化剂,该催化剂是指以质量分数计,由1～10%的助剂MO-(x)、30%～70%的活性组分Cu和载体组成的Cu-MO-(x)/载体；所述载体为MgO和SiO-(2)的混合物,且MgO占催化剂总量的5%～30%,催化剂余量为SiO-(2)；所述助剂MO-(x)是指In-(2)O-(3)、Pr-(2)O-(3)、Sm-(2)O-(3)、La-(2)O-(3)、CeO-(2)、Y-(2)O-(3)和MnO-(2)中的一种及以上。同时,本发明还公开了该催化剂的制备方法和应用。本发明方法简单、成本低,所得催化剂具有优异的分散度和稳定性,可在温和条件下实现甘油氢解高收率制备1,2-丙二醇,易实现工业化大规模生产。(The invention relates to a copper-silicon catalyst, which is formed by 1-10% of auxiliary agent MO by mass fraction x 30-70% of active component Cu and Cu-MO composed of carrier x A carrier; the carrier is MgO and SiO 2 And MgO accounts for 5-30% of the total amount of the catalyst, and the balance of the catalyst is SiO 2 (ii) a The auxiliary agent MO x Refers to In 2 O 3 、Pr 2 O 3 、Sm 2 O 3 、La 2 O 3 、CeO 2 、Y 2 O 3 And MnO 2 One or more of them. Meanwhile, the invention also discloses a preparation method and application of the catalyst. The method is simple and low in cost, the obtained catalyst has excellent dispersity and stability, the 1, 2-propylene glycol can be prepared at high yield by glycerol hydrogenolysis under mild conditions, and industrial large-scale production is easy to realize.)

1. A copper silicon catalyst characterized by: the catalyst is formed by 1-10% of auxiliary agent MO by mass fraction_x30-70% of active component Cu and Cu-MO composed of carrier_xA carrier; the carrier is MgO and SiO₂The MgO accounts for 5-30% of the total amount of the catalyst, and the balance of the catalyst is SiO₂(ii) a The auxiliary agent MO_xRefers to In₂O₃、Pr₂O₃、Sm₂O₃、La₂O₃、CeO₂、Y₂O₃And MnO₂One or more of them.

2. The method of claim 1, wherein the method comprises the steps of: firstly, converting the use amounts of copper salt, auxiliary agent metal salt, magnesium salt and silica sol according to the use amount of catalyst components, and then adding deionized water into the copper salt, the auxiliary agent metal salt and the magnesium salt to obtain 150 g/L salt solution; under the condition of vigorous stirring, dropwise adding a precipitator solution with the concentration of 100 g/L into the salt solution until the pH value of the salt solution is more than 11 to obtain a mixed solution; secondly, dropwise adding 10-30% silica sol into the mixed solution, aging at 50-80 ℃ for 4-24 h after dropwise adding, and filtering to obtain a precipitate; and finally, washing the precipitate, drying at 110 ℃ for 12h, roasting and reducing to obtain the catalyst.

3. The method of claim 2, wherein the method comprises the steps of: the copper salt is one or more than two of nitrate, sulfate, acetate and halide of copper.

4. The method of claim 2, wherein the method comprises the steps of: the adjuvant metal salt is In (NO)₃)₃·4H₂O、Pr(NO₃)₃·6H₂O、Sm(NO₃)₃·6H₂O、La(NO₃)₃·6H₂O、Ce(NO₃)₃·6H₂O、Y(NO₃)₃·6H₂O and Mn (NO)₃)₂·4H₂And O is one of the compounds.

5. The method of claim 2, wherein the method comprises the steps of: the magnesium salt refers to at least one of nitrate, sulfate and halide of magnesium.

6. The method of claim 2, wherein the method comprises the steps of: the precipitant solution is one or more of sodium hydroxide solution, potassium hydroxide solution, sodium carbonate solution, sodium bicarbonate solution, ammonia water solution, and urea solution.

7. The method of claim 2, wherein the method comprises the steps of: the roasting is carried out in static air at the temperature of 300-800 ℃ for 2-12 h.

8. The method of claim 2, wherein the method comprises the steps of: the reduction is carried out in a flowing atmosphere at the temperature of 200-500 ℃ for 2-12 h; the reducing atmosphere is hydrogen or 10-90% of mixed hydrogen and nitrogen.

9. The use of a copper silicon catalyst according to claim 1, wherein: the catalyst is applied to the reaction for preparing the 1, 2-propylene glycol by selective hydrogenolysis of glycerol, wherein the reactor is an autoclave type reactor or a high-pressure fixed bed continuous reactor, the reaction temperature is 160-240 ℃, and the hydrogen reaction pressure is 1-8 MPa.

10. Use of a copper silicon catalyst according to claim 9, wherein: in the autoclave reactor, the mass ratio of the catalyst to the glycerol is 1:16, and the reaction time is 4-12 h.

11. Use of a copper silicon catalyst according to claim 9, wherein: in the high-pressure fixed bed continuous reactor, the mass airspeed of the glycerol is 0.25-1.5 h^-1The molar ratio of hydrogen to glycerol is 10-25.

Technical Field

The invention relates to the field of catalysts, and particularly relates to a copper-silicon catalyst and a preparation method and application thereof.

Background

1, 2-propylene glycol is an important unsaturated polyester synthetic monomer, is a basic raw material for preparing epoxy resin, polyurethane resin, a plasticizer and a surfactant, and is widely applied to industries such as food, medicine, cosmetics and the like. Currently, 1, 2-propanediol is produced in industry via hydration mainly as the nonrenewable petrochemical propylene oxide. In recent years, with the rapid increase of the demand and the yield of the biodiesel, the capacity of the byproduct glycerol is greatly surplus, and a new method for preparing the 1, 2-propylene glycol by taking the biological glycerol as the raw material is provided for the large-scale production of the biological glycerol.

The selective hydrogenolysis of glycerol to prepare 1, 2-propylene glycol is continuously concerned, the development of a high-efficiency and stable catalytic hydrogenolysis system is the key for realizing the process, and the Cu-based catalyst is the most ideal catalytic effect at present. As early as 1993, U.S. Pat. No. 5,973,97 discloses a process for the selective hydrogenolysis of glycerol to 1, 2-propanediol using a supported Cu-Zn bimetallic catalyst, but the process is harsh (temperature)>At 220 ℃ and hydrogen pressure>10 MPa), large catalyst dosage, low reaction substrate concentration and difficult application in industrial production. Chinese patents CN200610105255.X, CN200710305964.7, CN201110292276.8 and the like disclose nano CuO-SiO modified by different assistants₂Although the catalyst shows good initial reaction performance under the hydrogen reaction conditions of 180-200 ℃ and 3-6 MPa, the reaction stability of the catalyst needs to be improved, and the industrial application prospect of the catalyst is limited. Chinese patents CN200710020031.3, CN201110062939.7 and CN 201610178462.1 and research papers (appl. Catal. B, 2011, 101, 431) respectively report Cu-Al modified by different assistants prepared by using hydrotalcite as precursor₂O₃The catalyst, however, has low activity, needs to raise the reaction temperature to increase the conversion rate of glycerol, and is difficult to ensure the selectivity of 1, 2-propylene glycol at higher temperature, and simultaneously, due to the memory effect of hydrotalcite structureIt should be difficult to shape the catalyst and keep the structure stable in the reaction system, and is not suitable for continuous industrial production.

In conclusion, the development of the copper-based catalyst suitable for preparing 1, 2-propanediol by selective hydrogenolysis of glycerol still has the problems of low catalytic activity and/or target product selectivity, harsh reaction conditions, insufficient catalyst stability, high requirements on equipment and the like, and further increases the industrialization difficulty of the process.

Disclosure of Invention

The invention aims to solve the technical problem of providing a copper-silicon catalyst with high dispersity and good stability.

The invention also aims to provide a preparation method of the copper-silicon catalyst.

The third technical problem to be solved by the invention is to provide the application of the copper-silicon catalyst.

In order to solve the above problems, the copper-silicon catalyst of the present invention is characterized in that: the catalyst is formed by 1-10% of auxiliary agent MO by mass fraction_x30-70% of active component Cu and Cu-MO composed of carrier_xA carrier; the carrier is MgO and SiO₂The MgO accounts for 5-30% of the total amount of the catalyst, and the balance of the catalyst is SiO₂(ii) a The auxiliary agent MO_xRefers to In₂O₃、Pr₂O₃、Sm₂O₃、La₂O₃、CeO₂、Y₂O₃And MnO₂One or more of them.

The preparation method of the copper-silicon catalyst is characterized by comprising the following steps: firstly, converting the use amounts of copper salt, auxiliary agent metal salt, magnesium salt and silica sol according to the use amount of catalyst components, and then adding deionized water into the copper salt, the auxiliary agent metal salt and the magnesium salt to obtain 150 g/L salt solution; under the condition of vigorous stirring, dropwise adding a precipitator solution with the concentration of 100 g/L into the salt solution until the pH value of the salt solution is more than 11 to obtain a mixed solution; secondly, dropwise adding 10-30% silica sol into the mixed solution, aging at 50-80 ℃ for 4-24 h after dropwise adding, and filtering to obtain a precipitate; and finally, washing the precipitate, drying at 110 ℃ for 12h, roasting and reducing to obtain the catalyst.

The copper salt is one or more than two of nitrate, sulfate, acetate and halide of copper.

The adjuvant metal salt is In (NO)₃)₃·4H₂O、Pr(NO₃)₃·6H₂O、Sm(NO₃)₃·6H₂O、La(NO₃)₃·6H₂O、Ce(NO₃)₃·6H₂O、Y(NO₃)₃·6H₂O and Mn (NO)₃)₂·4H₂And O is one of the compounds.

The magnesium salt refers to at least one of nitrate, sulfate and halide of magnesium.

The precipitant solution is one or more of sodium hydroxide solution, potassium hydroxide solution, sodium carbonate solution, sodium bicarbonate solution, ammonia water solution, and urea solution.

The roasting is carried out in static air at the temperature of 300-800 ℃ for 2-12 h.

The reduction is carried out in a flowing atmosphere at the temperature of 200-500 ℃ for 2-12 h; the reducing atmosphere is hydrogen or 10-90% of mixed hydrogen and nitrogen.

The application of the copper-silicon catalyst is characterized in that: the catalyst is applied to the reaction for preparing the 1, 2-propylene glycol by selective hydrogenolysis of glycerol, wherein the reactor is an autoclave type reactor or a high-pressure fixed bed continuous reactor, the reaction temperature is 160-240 ℃, and the hydrogen reaction pressure is 1-8 MPa.

In the autoclave reactor, the mass ratio of the catalyst to the glycerol is 1:16, and the reaction time is 4-12 h.

In the high-pressure fixed bed continuous reactor, the mass airspeed of the glycerol is 0.25-1.5 h^-1The molar ratio of hydrogen to glycerol is 10-25.

Compared with the prior art, the invention has the following advantages:

1. the invention uses MgO and SiO₂The bifunctional composite oxide is used as a carrier and can be adjusted to two kindsThe proper acid-base sites are obtained according to the proportion, and meanwhile, the composite oxides interact with each other, so that the catalyst has larger pore diameter and pore volume, and the diffusion speed of glycerol molecules in the catalyst is promoted, thereby improving the adsorption and desorption and reaction rate of the substrate on the surface of the catalyst, and being beneficial to improving the catalytic activity and the selectivity of a target product.

2. The interaction between the carrier and the active metal Cu is strong, and the addition of the metal oxide auxiliary agent effectively reduces the sintering rate of Cu, thereby being beneficial to improving the stability of the catalyst and solving the problem of poor stability of the traditional copper-silicon catalyst.

3. The catalyst is prepared by adopting a simple acid-base neutralization precipitation method, so that the preparation process is simple, the production cost is low, and the catalyst is suitable for industrial application.

4. The catalyst has high catalytic performance and good stability in the reaction of preparing the 1, 2-propylene glycol by selective hydrogenolysis of the glycerol, can realize the high-yield preparation of the 1, 2-propylene glycol by hydrogenolysis of the glycerol under mild conditions, and is easy to realize industrial large-scale production.

Detailed Description

The copper-silicon catalyst is characterized by comprising 1-10% of auxiliary agent MO by mass fraction_x30-70% of active component Cu and Cu-MO composed of carrier_xA carrier. The carrier is MgO and SiO₂The MgO accounts for 5-30% of the total amount of the catalyst, and the balance of the catalyst is SiO₂(ii) a Adjuvant MO_xRefers to In₂O₃、Pr₂O₃、Sm₂O₃、La₂O₃、CeO₂、Y₂O₃And MnO₂One or more of them.

The preparation method of the copper-silicon catalyst comprises the following steps:

firstly, converting the use amounts of copper salt, auxiliary agent metal salt, magnesium salt and silica sol according to the use amount of catalyst components, and then adding deionized water into the copper salt, the auxiliary agent metal salt and the magnesium salt to obtain 150 g/L salt solution; under vigorous stirring, dropwise adding a precipitator solution with the concentration of 100 g/L into the salt solution until the pH value of the salt solution is more than 11 to obtain a mixed solution; secondly, dropwise adding 10-30% silica sol into the mixed solution, aging at 50-80 ℃ for 4-24 h after dropwise adding, and filtering to obtain a precipitate; and finally, washing the precipitate, drying at 110 ℃ for 12h, roasting and reducing to obtain the catalyst.

Wherein: the copper salt is one or more than two of nitrate, sulfate, acetate and halide of copper.

The adjuvant metal salt is In (NO)₃)₃·4H₂O、Pr(NO₃)₃·6H₂O、Sm(NO₃)₃·6H₂O、La(NO₃)₃·6H₂O、Ce(NO₃)₃·6H₂O、Y(NO₃)₃·6H₂O and Mn (NO)₃)₂·4H₂And O is one of the compounds.

The magnesium salt is at least one of nitrate, sulfate and halide of magnesium.

The precipitant solution is one or more of sodium hydroxide solution, potassium hydroxide solution, sodium carbonate solution, sodium bicarbonate solution, ammonia water solution, and urea solution.

The roasting is carried out in static air at the temperature of 300-800 ℃ for 2-12 h.

The reduction refers to reduction in a flowing atmosphere, wherein the temperature is 200-500 ℃, and the time is 2-12 hours; the reducing atmosphere is hydrogen or 10-90% of mixed hydrogen and nitrogen.

Example 1A copper-silicon catalyst comprising, in parts by weight, 60% Cu as the active metal and CeO as the auxiliary₂The content of the magnesium oxide is 4 percent, the content of the magnesium oxide as the carrier is 11 percent, and the balance is SiO as the carrier₂。

The preparation method comprises the following steps: weighing 57.07g Cu (NO)₃)₂·3H₂O、17.50g Mg(NO₃)₂·6H₂O and 2.52g Ce (NO)₃)₃·6H₂Adding 510 mL of deionized water into O to obtain 150 g/L of salt solution; under vigorous stirring, dropwise adding 100 g/L sodium hydroxide solution into the salt solution until the pH value of the salt solution is more than 11 to obtain a mixed solution; 20.83 g of 30 wt% silica sol was added dropwise to the mixed solution, and after the addition was completed, the mixture was aged at 70 ℃Filtering after 4 h to obtain a precipitate; washing the precipitate, drying at 110 deg.C for 12 hr, and calcining at 500 deg.C in air atmosphere for 4 hr; at 20% H₂-N₂And reducing for 4 hours at 300 ℃ in the mixed gas flow to obtain the reduced catalyst A.

Example 2 a copper silicon catalyst, In parts by mass, the catalyst contains 30% Cu, an In promoter₂O₃1 percent of magnesium oxide as a carrier, 30 percent of SiO as a carrier and the balance₂。

The preparation method comprises the following steps: 28.54 g Cu (NO) was weighed₃)₂·3H₂O、47.72 g Mg(NO₃)₂·6H₂O and 0.33 g In (NO)₃)₃·4H₂Adding 510 mL of deionized water into O to obtain 150 g/L of salt solution; under vigorous stirring, dropwise adding 100 g/L sodium hydroxide solution into the salt solution until the pH value of the salt solution is more than 11 to obtain a mixed solution; 32.50 g of 30 wt% silica sol is added into the mixed solution dropwise, and after the addition is finished, the mixed solution is aged for 4 hours at 70 ℃ and then filtered to obtain a precipitate; washing the precipitate, drying at 110 deg.C for 12 hr, and calcining at 500 deg.C in air atmosphere for 4 hr; at 20% H₂-N₂And reducing for 4 hours at 300 ℃ in the mixed gas flow to obtain the reduced catalyst B.

Example 3 a copper-silicon catalyst comprising, in parts by mass, 70% Cu as the active metal and Pr as the promoter₂O₃10 percent of magnesium oxide as a carrier, 5 percent of magnesium oxide as a carrier and the balance of SiO as a carrier₂。

The preparation method comprises the following steps: weighing 66.58 g Cu (NO)₃)₂·3H₂O、7.95 g Mg(NO₃)₂·6H₂O and 3.30 g Pr (NO)₃)₃·6H₂Adding 520 mL of deionized water into O to obtain 150 g/L salt solution; under vigorous stirring, dropwise adding 100 g/L sodium hydroxide solution into the salt solution until the pH value of the salt solution is more than 11 to obtain a mixed solution; 32.50 g of 30 wt% silica sol is added into the mixed solution dropwise, and after the addition is finished, the mixed solution is aged for 4 hours at 70 ℃ and then filtered to obtain a precipitate; washing the precipitate, drying at 110 deg.C for 12 hr, and air dryingRoasting at 500 ℃ for 4 h; at 20% H₂-N₂And reducing for 4 hours at 300 ℃ in the mixed gas flow to obtain the reduced catalyst C.

Example 4A copper-silicon catalyst, comprising 60% by weight of Cu as an active metal and Sm as an auxiliary₂O₃The content of the magnesium oxide is 4 percent, the content of the magnesium oxide as the carrier is 11 percent, and the balance is SiO as the carrier₂。

The preparation method comprises the following steps: weighing 57.07g Cu (NO)₃)₂·3H₂O、17.50 g Mg(NO₃)₂·6H₂O and 1.27 g Sm (NO)₃)₃·6H₂Adding 510 mL of deionized water into O to obtain 150 g/L of salt solution; under vigorous stirring, dropwise adding 100 g/L sodium hydroxide solution into the salt solution until the pH value of the salt solution is more than 11 to obtain a mixed solution; dropwise adding 62.50 g of 10 wt% silica sol into the mixed solution, aging at 80 ℃ for 4 h after dropwise adding, and filtering to obtain a precipitate; washing the precipitate, drying at 110 deg.C for 12 hr, and calcining at 500 deg.C in air atmosphere for 4 hr; at 20% H₂-N₂And reducing for 4 hours at 300 ℃ in the mixed gas flow to obtain the reduced catalyst D.

Example 5A copper-silicon catalyst containing 60% by mass of Cu as an active metal and La as an auxiliary₂O₃The content of the magnesium oxide is 4 percent, the content of the magnesium oxide as the carrier is 11 percent, and the balance is SiO as the carrier₂。

The preparation method comprises the following steps: weighing 57.07g Cu (NO)₃)₂·3H₂O、17.50 g Mg(NO₃)₂·6H₂O and 1.33 g La (NO)₃)₃·6H₂Adding 510 mL of deionized water into O to obtain 150 g/L of salt solution; under vigorous stirring, dropwise adding 100 g/L sodium hydroxide solution into the salt solution until the pH value of the salt solution is more than 11 to obtain a mixed solution; dripping 20.83 g of 30 wt% silica sol into the mixed solution, aging at 50 ℃ for 24 h after the dripping is finished, and filtering to obtain a precipitate; washing the precipitate, drying at 110 deg.C for 12 hr, and calcining at 500 deg.C in air atmosphere for 4 hr; at 20% H₂-N₂Reducing for 4 h at 300 ℃ in a mixed gas flow to obtain reductionThe original catalyst E.

Example 6A copper-silicon catalyst containing 60% by mass of Cu as an active metal and Y as an auxiliary₂O₃The content of the magnesium oxide is 4 percent, the content of the magnesium oxide as the carrier is 11 percent, and the balance is SiO as the carrier₂。

The preparation method comprises the following steps: weighing 57.07g Cu (NO)₃)₂·3H₂O、17.50 g Mg(NO₃)₂·6H₂O and 1.70 g Y (NO)₃)₃·6H₂Adding 510 mL of deionized water into O to obtain 150 g/L of salt solution; under vigorous stirring, dropwise adding 100 g/L potassium hydroxide solution into the salt solution until the pH value of the salt solution is more than 11 to obtain a mixed solution; dripping 20.83 g of 30 wt% silica sol into the mixed solution, aging at 70 ℃ for 4 h after the dripping is finished, and filtering to obtain a precipitate; washing the precipitate, drying at 110 deg.C for 12 hr, and calcining at 300 deg.C in air atmosphere for 12 hr; at 20% H₂-N₂And reducing for 4 hours at 300 ℃ in the mixed gas flow to obtain a reduced catalyst F.

Example 7A copper-silicon catalyst containing 60% by mass of Cu as an active metal and MnO as an auxiliary₂The content of the magnesium oxide is 4 percent, the content of the magnesium oxide as the carrier is 11 percent, and the balance is SiO as the carrier₂。

The preparation method comprises the following steps: weighing 57.07g Cu (NO)₃)₂·3H₂O、17.50 g Mg(NO₃)₂·6H₂O and 2.80 g Mn (NO)₃)₂·4H₂Adding 520 mL of deionized water into O to obtain 150 g/L salt solution; under vigorous stirring, dropwise adding 100 g/L sodium carbonate solution into the salt solution until the pH value of the salt solution is more than 11 to obtain a mixed solution; dripping 20.83 g of 30 wt% silica sol into the mixed solution, aging at 70 ℃ for 4 h after the dripping is finished, and filtering to obtain a precipitate; washing the precipitate, drying at 110 deg.C for 12 hr, and calcining at 800 deg.C in air atmosphere for 2 hr; at 20% H₂-N₂And reducing the mixture for 4 hours at 300 ℃ in the mixed gas flow to obtain a reduced catalyst G.

Example 8A copper silicon catalyst in parts by weightThe active metal Cu content in the catalyst is 60%, and the auxiliary agent CeO₂The content of the magnesium oxide is 4 percent, the content of the magnesium oxide as the carrier is 11 percent, and the balance is SiO as the carrier₂。

The preparation method comprises the following steps: weighing 57.07g Cu (NO)₃)₂·3H₂O、17.50 g Mg(NO₃)₂·6H₂O and 2.52g Ce (NO)₃)₃·6H₂Adding 510 mL of deionized water into O to obtain 150 g/L of salt solution; under the condition of vigorous stirring, dropwise adding 100 g/L sodium bicarbonate solution into the saline solution until the pH value of the saline solution is more than 11 to obtain a mixed solution; dripping 20.83 g of 30 wt% silica sol into the mixed solution, aging at 70 ℃ for 4 h after the dripping is finished, and filtering to obtain a precipitate; washing the precipitate, drying at 110 deg.C for 12 hr, and calcining at 500 deg.C in air atmosphere for 4 hr; at 20% H₂-N₂And reducing the mixture for 4 hours at 300 ℃ in the mixed gas flow to obtain a reduced catalyst H.

Example 9A copper-silicon catalyst comprising, in parts by weight, 60% Cu as the active metal and CeO as the auxiliary₂The content of the magnesium oxide is 4 percent, the content of the magnesium oxide as the carrier is 11 percent, and the balance is SiO as the carrier₂。

The preparation method comprises the following steps: weighing 57.07g Cu (NO)₃)₂·3H₂O、17.50 g Mg(NO₃)₂·6H₂O and 2.52g Ce (NO)₃)₃·6H₂Adding 510 mL of deionized water into O to obtain 150 g/L of salt solution; under vigorous stirring, dropwise adding 100 g/L ammonia water solution into the salt solution until the pH value of the salt solution is more than 11 to obtain a mixed solution; dripping 20.83 g of 30 wt% silica sol into the mixed solution, aging at 70 ℃ for 4 h after the dripping is finished, and filtering to obtain a precipitate; washing the precipitate, drying at 110 deg.C for 12 hr, and calcining at 500 deg.C in air atmosphere for 4 hr; at 20% H₂-N₂And reducing for 4 hours at 300 ℃ in the mixed gas flow to obtain the reduced catalyst I.

Example 10A copper-silicon catalyst containing 60% by weight of Cu as an active metal and CeO as an auxiliary₂The content of the magnesium oxide is 4 percent, the content of the magnesium oxide as the carrier is 11 percent, and the balance is SiO as the carrier₂。

The preparation method comprises the following steps: weighing 57.07g Cu (NO)₃)₂·3H₂O、17.50 g Mg(NO₃)₂·6H₂O and 2.52g Ce (NO)₃)₃·6H₂Adding 510 mL of deionized water into O to obtain 150 g/L of salt solution; under vigorous stirring, dropwise adding 100 g/L urea solution into the saline solution until the pH value of the saline solution is more than 11 to obtain a mixed solution; dripping 20.83 g of 30 wt% silica sol into the mixed solution, aging at 70 ℃ for 4 h after the dripping is finished, and filtering to obtain a precipitate; washing the precipitate, drying at 110 deg.C for 12 hr, and calcining at 500 deg.C in air atmosphere for 4 hr; at 20% H₂-N₂And reducing for 4 hours at 300 ℃ in the mixed gas flow to obtain the reduced catalyst J.

Example 11 a copper-silicon catalyst having an active metal Cu content of 60% and an auxiliary CeO₂The content of the magnesium oxide is 4 percent, the content of the magnesium oxide as the carrier is 11 percent, and the balance is SiO as the carrier₂。

The preparation method comprises the following steps: 58.98 g of Cu (SO) were weighed out₄)₂·5H₂O、16.82 g Mg(SO₄)₂·7H₂O and 2.52g Ce (NO)₃)₃·6H₂Adding 520 mL of deionized water into O to obtain 150 g/L salt solution; under vigorous stirring, dropwise adding 100 g/L sodium hydroxide solution into the salt solution until the pH value of the salt solution is more than 11 to obtain a mixed solution; dripping 20.83 g of 30 wt% silica sol into the mixed solution, aging at 70 ℃ for 4 h after the dripping is finished, and filtering to obtain a precipitate; washing the precipitate, drying at 110 deg.C for 12 hr, and calcining at 500 deg.C in air atmosphere for 4 hr; and reducing the mixture for 12 hours at 200 ℃ in a pure hydrogen flow to obtain the reduced catalyst K.

Example 12A copper-silicon catalyst comprising, in parts by weight, 60% Cu as the active metal and CeO as the auxiliary₂The content of the magnesium oxide is 4 percent, the content of the magnesium oxide as the carrier is 11 percent, and the balance is SiO as the carrier₂。

The preparation method comprises the following steps: 47.15 g Cu (OAc) are weighed out₂·H₂O、17.50 g Mg(NO₃)₂·6H₂O and 2.52g Ce (NO)₃)₃·6H₂Adding 450 mL of deionized water into O to obtain 150 g/L salt solution; under vigorous stirring, dropwise adding 100 g/L ammonia water solution into the salt solution until the pH value of the salt solution is more than 11 to obtain a mixed solution; dripping 20.83 g of 30 wt% silica sol into the mixed solution, aging at 70 ℃ for 4 h after the dripping is finished, and filtering to obtain a precipitate; washing the precipitate, drying at 110 deg.C for 12 hr, and calcining at 500 deg.C in air atmosphere for 4 hr; at 10% H₂-N₂And reducing the mixture for 2 hours at 500 ℃ in the mixed gas flow to obtain a reduced catalyst L.

Example 13A copper-silicon catalyst having an active metal Cu content of 60% and an auxiliary CeO₂The content of the magnesium oxide is 4 percent, the content of the magnesium oxide as the carrier is 11 percent, and the balance is SiO as the carrier₂。

The preparation method comprises the following steps: 40.28 g of CuCl were weighed out₂·2H₂O、13.87 g MgCl₂·6H₂O and 2.52g Ce (NO)₃)₃·6H₂Adding 380 mL of deionized water into the O to obtain 150 g/L of salt solution; under vigorous stirring, dropwise adding 100 g/L ammonia water solution into the salt solution until the pH value of the salt solution is more than 11 to obtain a mixed solution; dripping 20.83 g of 30 wt% silica sol into the mixed solution, aging at 70 ℃ for 4 h after the dripping is finished, and filtering to obtain a precipitate; washing the precipitate, drying at 110 deg.C for 12 hr, and calcining at 500 deg.C in air atmosphere for 4 hr; at 90% H₂-N₂And reducing for 4 hours at 300 ℃ in the mixed gas flow to obtain the reduced catalyst M.

Application of the catalysts obtained in examples 1 to 13: the catalyst is applied to the reaction for preparing the 1, 2-propylene glycol by selective hydrogenolysis of glycerol, wherein the reactor is an autoclave type reactor or a high-pressure fixed bed continuous reactor, the reaction temperature is 160-240 ℃, and the hydrogen reaction pressure is 1-8 MPa.

Wherein: in the autoclave type reactor, the mass ratio of the catalyst to the glycerol is 1:16, and the reaction time is 4-12 h.

In the high-pressure fixed bed continuous reactor, the mass space velocity of the glycerol is 0.25-1.5 h^-1Moles of Hydrogen and GlycerolThe ratio is 10 to 25.

The catalysts obtained in examples 1 to 13 were evaluated for catalytic performance by the following method:

1 g of the reduced catalyst, 16 g of glycerol and 24 g of methanol are added into a 100 mL autoclave reactor, and high-purity hydrogen is adopted to replace the catalyst for 3 times at room temperature, and then the temperature is increased to 180 ℃ for reaction for 12 hours. The evaluation results are shown in Table 1.

The catalyst A obtained in example 1 was subjected to the evaluation of the influence of catalytic performance under different reaction conditions by the methods of examples 14 to 17, and the evaluation results are shown in Table 1.

Example 14 1 g of reduced catalyst a was charged into a 100 mL autoclave reactor together with 16 g of glycerol and 24 g of methanol, and after 3 times of replacement at room temperature with high-purity hydrogen, the pressure was increased to 8.0 MPa, the temperature was raised to 160 ℃, and the reaction was carried out for 12 hours.

Example 15 1 g of reduced catalyst a was charged into a 100 mL autoclave reactor together with 16 g of glycerol and 24 g of methanol, and after 3 times of replacement at room temperature with high-purity hydrogen, the pressure was increased to 1.0 MPa, the temperature was raised to 240 ℃ and the reaction was carried out for 4 hours.

Example 16A molded catalyst A calcined at 20-60 mesh was placed in a high pressure fixed bed flow reactor at 20% H₂-N₂Reducing for 4 h at 300 ℃ in mixed gas flow, starting feeding after the temperature is reduced to the reaction temperature, wherein the reaction temperature is 200 ℃, the concentration of raw materials is 40 percent of glycerol-methanol solution, the reaction pressure of hydrogen is 4.0 MPa, and the mass space velocity of glycerol is 0.25 h^-1The molar ratio of hydrogen to glycerol was 25.

Example 17A molded catalyst A calcined at 20-60 mesh was placed in a high pressure fixed bed flow reactor at 20% H₂-N₂Reducing for 4 h at 300 ℃ in mixed gas flow, starting feeding after the temperature is reduced to the reaction temperature, wherein the reaction temperature is 240 ℃, the concentration of raw materials is 40 percent of glycerol-methanol solution, the reaction pressure of hydrogen is 4.0 MPa, and the mass space velocity of glycerol is 1.5 h^-1The molar ratio of hydrogen to glycerol was 10.

TABLE 1 evaluation results

As can be seen from the performance evaluation of the reaction for preparing 1, 2-propanediol by selective hydrogenolysis of glycerol carried out by the catalysts obtained in the above examples 1 to 13, under the action of the catalysts prepared in the examples 1 to 13, by adopting appropriate reaction conditions, excellent glycerol conversion rate and 1, 2-propanediol selectivity can be obtained, and the catalyst has an industrial application prospect.