A high-selectivity catalyst for hydrogenating methyl 3-hydroxypropionate to 1,3-propylene glycol and a preparation method thereof

Abstract

The present invention discloses a highly selective catalyst for hydrogenating methyl 3-hydroxypropionate to 1,3-propylene glycol and a preparation method thereof. The catalyst is prepared using a deposition precipitation method and comprises the following components: (a) a main component, CuO; (b) an electron-enhancing agent, zirconium nitride; (c) one or more hydrogenation-activating agents, selected from Ag, Au, and Pt; and (d) a carrier and a pore-enlarging agent, SiO2. The hydrogenation-activating agent in the catalyst helps activate hydrogen, and the electron-enhancing agent, zirconium nitride, reacts with the main component, CuO, to form active sites that enhance the conversion of 1,3-propylene glycol. Therefore, the catalyst exhibits high activity for hydrogenating methyl 3-hydroxypropionate to 1,3-propylene glycol, improving the selectivity of the main product, 1,3-propylene glycol, and addressing the issues of low activity and low selectivity of existing catalysts.

Description

Technical Field

[0001] The invention belongs to the field of catalyst preparation, and particularly relates to a composite catalyst for hydrogenating methyl 3-hydroxypropionate to produce 1,3-propylene glycol and a preparation method thereof. Background Art

[0002] 1,3-Propanediol (1,3-PDO) is a colorless, odorless, salty, and hygroscopic viscous liquid. 1,3-PDO is not only a raw material for the production of unsaturated polyesters, plasticizers, surfactants, emulsifiers, and demulsifiers, but also a key ingredient in the synthesis of PTT (polytrimethylene terephthalate) fibers. Compared to fibers like PET, PBT, and PA6, PTT offers superior resilience and dyeability, enabling the development of personalized fashion fabrics characterized by comfort, elasticity, rich colors, and diverse weaves. As PTT fiber production technology matures and costs decrease, it could gradually replace 5-10% of traditional polyester fibers at a reasonable price point. The market prospects are promising, and the synthesis of 1,3-PDO has garnered considerable attention.

[0003] The only way to achieve the scalable and inexpensive production of 1,3-PDO is to use ethylene oxide hydromethylation to produce the intermediate methyl 3-hydroxypropionate, followed by catalytic hydrogenation. This method offers low raw material costs and is easily scaled up for large-scale production, providing an inexpensive raw material for the mass production of PTT fibers. In this method, the intermediate methyl 3-hydroxypropionate is hydrogenated to produce 1,3-propylene glycol. Because the β-hydroxy group in methyl 3-hydroxypropionate is more easily removed by hydrogenation than by ester hydrogenation, this creates more suitable active sites for ester hydrogenation, significantly improving the selectivity of the main product, 1,3-propylene glycol.

[0004] Copper-based catalysts for the hydrogenation of methyl 3-hydroxypropionate have become a research hotspot due to their low production cost, high activity, high selectivity, mild reaction conditions, and excellent toxicity resistance when combined with other active agents. Patent CN 101385980A reports a copper-based binary catalyst prepared using an organosilane as a carrier precursor and manganese as an active agent. A copper salt, manganese salt, and organosilane are mixed, dissolved in an alcohol-water solvent, and then heated and stirred to form a sol-gel. This catalyst exhibits low-temperature hydrogenation catalytic activity. Patent CN 1911507A employs a method in which an organic amine is pre-complexed with the copper salt in an alcohol solvent, fatty alcohol orthosilicate and aluminum fatty alcohol are added as carrier precursors, and then a gelling agent is added and heated to form a sol-gel. This method produces a low-loading copper-based single-component catalyst, effectively improving the catalyst's sintering resistance and service life. However, because the preparation process uses only copper as a single component, its catalytic activity remains to be improved. Furthermore, the use of an organic amine reagent produces a pungent odor, making it unfriendly to humans and the environment. Patent CN 106111155A reports the use of silica-supported catalysts containing the active main component Cu and one or more of the active additives Zn, Zr, Mn, La, P, Mo, and Ni, prepared by co-precipitation of an alkaline precipitant with a mixture of metal ions. This catalyst achieves high activity and selectivity. Patent CN 106179361A and Li Weijie's 2023 paper, "Selective Hydrogenation of Methyl 3-Hydroxypropionate over Zirconium-Modified Cu / SiO2 Catalyst," both mention the use of ZrO2 as a catalyst promoter in the hydrogenation of methyl 3-hydroxypropionate, demonstrating that the addition of ZrO2 effectively increases the catalyst's specific surface area and promotes the dispersion of the Cu active species. Patent CN 115155627A reports the use of zirconium phosphate as a catalyst promoter in the modification of a CuO-based catalyst. Zirconium phosphate, as a good proton conductor, maintains suitable active sites in the reaction, promoting the adsorption of ester groups in methyl 3-hydroxypropionate, thereby increasing the selectivity of the main product, 1,3-propylene glycol. Summary of the Invention

[0005] Aiming at the problems of low activity, many side reactions and low selectivity of 1,3-propylene glycol in existing 3-hydroxypropionate hydrogenation catalysts, the present invention provides a composite catalyst for hydrogenating 3-hydroxypropionate to 1,3-propylene glycol and a preparation method thereof.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] A highly selective catalyst for hydrogenating methyl 3-hydroxypropionate to 1,3-propylene glycol, comprising the following components:

[0008] (a) Main component CuO;

[0009] (b) electronic auxiliary agent zirconium nitride;

[0010] (c) hydrogenation activating agent;

[0011] (d) Carrier and pore-enlarging agent SiO2.

[0012] Furthermore, based on the sum of weight percentages being 100%, the contents of the components are: main component 20-60%, electronic auxiliary agent 2-10%, hydrogenation active auxiliary agent 0.1-5%, and SiO2 20-40%.

[0013] Furthermore, the crystal structure of the zirconium nitride is ZrN or Zr3N4.

[0014] Furthermore, the hydrogenation active agent is one or more of Ag, Pt, and Au.

[0015] The preparation method of the catalyst for hydrogenating methyl 3-hydroxypropionate to 1,3-propylene glycol with high selectivity comprises the following steps:

[0016] (1) Dissolve the CuO precursor and the hydrogenation active agent precursor in deionized water and stir for 30 minutes to obtain a transparent solution;

[0017] (2) adding an electronic auxiliary agent to the transparent solution obtained in step (1) and stirring thoroughly for 4 hours;

[0018] (3) Then, silica sol was slowly added dropwise to the mixed solution obtained in step (2), stirred thoroughly for 1 hour, and then transferred to a 70°C water bath and stirred for another 2 hours;

[0019] (4) Slowly add 0.5 mol / L sodium hydroxide solution to the suspension formed in step (3) until the pH is 6.5-8.0, and then precipitate and age in a water bath at 70-90 °C for 4-12 hours;

[0020] (5) The precipitate obtained in step (4) is filtered and washed until neutral, and then dried in an oven at 80-150°C for 4-40 hours;

[0021] (6) calcining the dried solid obtained in step (5) at 300-750°C for 4-24 hours to obtain the catalyst.

[0022] Furthermore, the precursor of CuO in step (1) is one or more of copper nitrate, copper sulfate, copper acetate, and copper chloride, preferably copper nitrate.

[0023] Furthermore, the precursor of the hydrogenation active agent in step (1) is one or more soluble salts such as nitrate, hydrochloride, acetate, etc., preferably silver nitrate or platinum nitrate.

[0024] Furthermore, the silica sol in step (3) is one of acidic silica sol, neutral silica sol and alkaline silica sol, preferably acidic silica sol.

[0025] Furthermore, the drying in step (5) is vacuum drying or normal pressure drying.

[0026] Furthermore, the calcination atmosphere in step (6) is air.

[0027] The obtained catalyst can be used for hydrogenation of methyl 3-hydroxypropionate to 1,3-propylene glycol. The specific operation is as follows: the catalyst loading amount is 20.0 ml. Before feeding, the catalyst is reduced with hydrogen to make the active component exist in the form of a single substance. The reduction conditions are: temperature 200-450 ° C, pressure 0.1-8.0 MPa, hydrogen flow rate 10-200 ml / min, time 0.5-36 h. During the reaction, methyl 3-hydroxypropionate is diluted with methanol to a mass concentration of 5-20%, temperature 140-200 ° C, pressure 3-8 MPa, and raw material space velocity 0.01-3.0 h -1 , hydrogen ester molar ratio 10-200.

[0028] The significant advantages of the present invention are:

[0029] The present invention adopts a deposition precipitation method to form a high-selectivity catalyst using the main catalyst CuO, hydrogenation active agent, electronic auxiliary agent zirconium nitride and carrier SiO2. Among them, the hydrogenation active agent Ag, Pt, and Au can reduce the reduction temperature of CuO and increase the reduction degree, thereby improving the catalyst's ability to activate hydrogen; using zirconium nitride as an electronic auxiliary can stabilize the CuO generated during the reaction. + / Cu 0 active sites, promoting the adsorption of the ester group in methyl 3-hydroxypropionate, thereby improving the selectivity of 1,3-propylene glycol. DETAILED DESCRIPTION

[0030] A highly selective catalyst for hydrogenating methyl 3-hydroxypropionate to 1,3-propylene glycol comprises, based on the total weight percentage being 100%, 20-60% of a main component of CuO, 2-10% of an electronic auxiliary agent of zirconium nitride, 0.1-5% of one or more of hydrogenation active auxiliary agents of Ag, Pt, and Au, and 20-40% of a carrier and pore-enlarging agent of SiO2.

[0031] The preparation method of the catalyst for hydrogenating methyl 3-hydroxypropionate to 1,3-propylene glycol with high selectivity comprises the following steps:

[0032] (1) Dissolve the CuO precursor and the hydrogenation active agent precursor in deionized water and stir for 30 minutes to obtain a transparent solution;

[0033] (2) adding an electronic auxiliary agent to the transparent solution obtained in step (1) and stirring thoroughly for 4 hours;

[0034] (3) Then, silica sol was slowly added dropwise to the mixed solution obtained in step (2), stirred thoroughly for 1 hour, and then transferred to a 70°C water bath and stirred for another 2 hours;

[0035] (4) Slowly add 0.5 mol / L sodium hydroxide solution to the suspension formed in step (3) until the pH is 6.5-8.0, and then precipitate and age in a water bath at 70-90 °C for 4-12 hours;

[0036] (5) The precipitate obtained in step (4) is filtered and washed until neutral, and then dried in an oven at 80-150°C for 4-40 hours;

[0037] (6) calcining the dried solid obtained in step (5) at 300-750°C for 4-24 hours to obtain the catalyst.

[0038] Wherein, the precursor of CuO in step (1) is one or more of copper nitrate, copper sulfate, copper acetate, and copper chloride. The precursor of the hydrogenation active agent is one or more of soluble salts such as nitrate, hydrochloride, and acetate.

[0039] The silica sol in step (3) is one of acidic silica sol, neutral silica sol and alkaline silica sol.

[0040] In order to make the contents of the present invention easier to understand, the technical solutions of the present invention are further described below in conjunction with specific implementation methods, but the present invention is not limited thereto.

[0041] Example 135CuO-0.5Ag-4ZrN / 60.5SiO2

[0042] 10.63 g of copper nitrate trihydrate and 0.079 g of silver nitrate were weighed and dissolved in 50 ml of deionized water. The solution was stirred for 30 minutes until transparent. 0.4 g of ZrN powder was then added to the solution and stirred for 4 hours to allow the inorganic salts to mix and absorb into the zirconium nitride. 20.17 g of 30% silica sol was then slowly added dropwise. After stirring for 1 hour, the suspension was transferred to a 70°C water bath and stirred for an additional 2 hours. 100 ml of 0.5 mol / L sodium hydroxide solution was slowly added dropwise to the suspension until the pH reached 7.1. The suspension was then aged in a 90°C water bath for 6 hours. The precipitate was filtered, washed to neutrality, and then dried in a 120°C oven for 10 hours. The resulting solid was calcined at 550°C for 6 hours to obtain the catalyst 35CuO-0.5Ag-4ZrN / 60.5SiO2. The resulting catalyst was compacted and sieved into 20-40 mesh granules.

[0043] Comparative Example 135CuO-0.5Ag / 64.5SiO2

[0044] 10.63 g of copper nitrate trihydrate and 0.079 g of silver nitrate were weighed and dissolved in 50 ml of deionized water. The solution was stirred for 30 minutes until transparent. 21.5 g of silica sol was then slowly added dropwise. After stirring for 1 hour, the solution was transferred to a 70°C water bath and stirred for an additional 2 hours. 100 ml of 0.5 mol / L sodium hydroxide solution was slowly added dropwise to the suspension until the pH reached 7.0. The suspension was then aged in a 90°C water bath for 6 hours. The precipitate was filtered, washed to neutrality, and then dried in a 120°C oven for 10 hours. The resulting solid was calcined at 550°C for 6 hours to obtain the catalyst 35CuO-0.5Ag / 64.5SiO2. The resulting catalyst was compacted, crushed, and sieved into 20-40 mesh granules.

[0045] Comparative Example 235CuO-4ZrN / 61SiO2

[0046] 10.63 g of copper nitrate trihydrate was weighed and dissolved in 50 ml of deionized water. The solution was stirred for 30 minutes until transparent. 0.4 g of ZrN powder was then added to the solution and stirred for 4 hours to allow the inorganic salt to mix and absorb with the zirconium nitride. 20.3 g of 30% silica sol was then slowly added dropwise. After stirring for 1 hour, the suspension was transferred to a 70°C water bath and stirred for an additional 2 hours. 100 ml of 0.5 mol / L sodium hydroxide solution was slowly added dropwise to the suspension until the pH reached 7.1. The suspension was then aged in a 90°C water bath for 6 hours. The precipitate was filtered, washed to neutrality, and then dried in a 120°C oven for 10 hours. The resulting solid was calcined at 550°C for 6 hours to obtain the catalyst 35CuO-4ZrN / 61SiO2. The resulting catalyst was compacted and sieved into 20-40 mesh granules.

[0047] Comparative Example 335CuO-0.5Ag / 4ZrN-61SiO2

[0048] 10.63 g of copper nitrate trihydrate and 0.079 g of silver nitrate were weighed and dissolved in 50 ml of deionized water. The solution was stirred for 30 minutes until transparent. 0.40 g of ZrN powder and 6.1 g of SiO2 powder were then added to the solution. After thorough stirring for 4 hours, the mixture was transferred to a 90°C waterbath and evaporated to dryness. The evaporated powder was then dried in a 120°C oven for 10 hours. The resulting solid was calcined at 550°C for 6 hours to obtain the catalyst 35CuO-0.5Ag / 4ZrN-61SiO2. The resulting catalyst was compacted and shaped, then crushed and sieved into 20-40 mesh granules.

[0049] Comparative Example 435CuO-0.5Ag-4ZrO2 / 60.5SiO2

[0050] 10.63 g of copper nitrate trihydrate and 0.079 g of silver nitrate were weighed and dissolved in 50 ml of deionized water. The solution was stirred for 30 minutes until transparent. 0.4 g of zirconium dioxide powder was then added to the solution and stirred for 4 hours to allow the inorganic salts to mix and absorb into the zirconium dioxide. 20.17 g of 30% silica sol was then slowly added dropwise. After stirring for 1 hour, the suspension was transferred to a 70°C water bath and stirred for an additional 2 hours. 100 ml of 0.5 mol / L sodium hydroxide solution was slowly added dropwise to the suspension until the pH reached 7.1. The suspension was then aged in a 90°C water bath for 6 hours. The precipitate was filtered, washed to neutrality, and then dried in a 120°C oven for 10 hours. The resulting solid was calcined at 550°C for 6 hours to obtain the catalyst 35CuO-0.5Ag-4ZrO2 / 60.5SiO2. The resulting catalyst was compacted, crushed, and sieved into 20-40 mesh granules.

[0051] Comparative Example 535CuO-0.5Ag-4ZrP / 60.5SiO2

[0052] 10.63 g of copper nitrate trihydrate and 0.079 g of silver nitrate were weighed and dissolved in 50 ml of deionized water. The solution was stirred for 30 minutes until transparent. 0.4 g of ZrP powder was then added to the solution and stirred for 4 hours to allow the inorganic salts to mix and absorb with the zirconium phosphate. 20.17 g of 30% silica sol was then slowly added dropwise. After stirring for 1 hour, the suspension was transferred to a 70°C water bath and stirred for an additional 2 hours. 100 ml of 0.5 mol / L sodium hydroxide solution was slowly added dropwise to the suspension until the pH reached 7.0. The suspension was then aged in a 90°C water bath for 6 hours. The precipitate was filtered, washed to neutrality, and then dried in a 120°C oven for 10 hours. The resulting solid was calcined at 550°C for 6 hours to obtain the catalyst 35CuO-0.5Ag-4ZrP / 60.5SiO2. The resulting catalyst was compacted, crushed, and sieved into 20-40 mesh granules.

[0053] Example 235CuO-0.3Pt-4ZrN / 60.7SiO2

[0054] 10.63 g of copper nitrate trihydrate and 0.049 g of platinum nitrate were weighed and dissolved in 50 ml of deionized water. The solution was stirred for 30 minutes until transparent. 0.40 g of ZrN powder was then added to the solution and stirred for 4 hours to allow the inorganic salts to mix and absorb into the zirconium nitride. 20.2 g of 30% silica sol was then slowly added dropwise. After stirring for 1 hour, the suspension was transferred to a 70°C water bath and stirred for an additional 2 hours. 100 ml of 0.5 mol / L sodium hydroxide solution was slowly added dropwise to the suspension until the pH reached 7.1. The suspension was then aged in a 90°C water bath for 6 hours. The precipitate was filtered, washed to neutrality, and then dried in a 120°C oven for 10 hours. The resulting solid was calcined at 550°C for 6 hours to obtain the catalyst 35CuO-0.3Pt-4ZrN / 60.7SiO2. The resulting catalyst was compacted, crushed, and sieved into 20-40 mesh granules.

[0055] Example 335CuO-0.2Au-4ZrN / 60.8SiO2

[0056] 10.63 g of copper nitrate trihydrate and 0.063 g of chloroauric acid were weighed and dissolved in 50 ml of deionized water. The solution was stirred for 30 minutes until the solution became transparent. 0.40 g of ZrN powder was then added to the solution and stirred for 4 hours to allow the inorganic salts to mix and absorb into the zirconium nitride. 20.3 g of 30% silica sol was then slowly added dropwise. After stirring for 1 hour, the suspension was transferred to a 70°C water bath and stirred for an additional 2 hours. 100 ml of 0.5 mol / L sodium hydroxide solution was slowly added dropwise to the suspension until the pH reached 7.1. The suspension was then aged in a 90°C water bath for 6 hours. The precipitate was filtered, washed to neutrality, and then dried in a 120°C oven for 10 hours. The resulting solid was calcined at 550°C for 6 hours to obtain the catalyst 35CuO-0.2Au-4ZrN / 60.8SiO2. The resulting catalyst was compacted and sieved into 20-40 mesh granules.

[0057] Example 435CuO-0.5Ag-4Zr3N4 / 60.7SiO2

[0058] 10.63 g of copper nitrate trihydrate and 0.079 g of silver nitrate were weighed and dissolved in 50 ml of deionized water. The solution was stirred for 30 minutes until transparent. 0.40 g of Zr3N4 powder was then added to the solution and stirred for 4 hours to allow the inorganic salts to mix and absorb with the zirconium nitride. 20.17 g of 30% silica sol was then slowly added dropwise. After stirring for 1 hour, the suspension was transferred to a 70°C water bath and stirred for an additional 2 hours. 100 ml of 0.5 mol / L sodium hydroxide solution was slowly added dropwise to the suspension until the pH reached 7.1. The suspension was then aged in a 90°C water bath for 6 hours. The precipitate was filtered, washed to neutrality, and then dried in a 120°C oven for 10 hours. The resulting solid was calcined at 550°C for 6 hours to obtain the catalyst 35CuO-0.5Ag-4ZrN / 60.5SiO2. The resulting catalyst was compacted, crushed, and sieved into 20-40 mesh granules.

[0059] Example 555CuO-0.5Ag-4ZrN / 40.5SiO2

[0060] 16.71 g of copper nitrate trihydrate and 0.079 g of silver nitrate were weighed and dissolved in 50 ml of deionized water. The solution was stirred for 30 minutes until transparent. 0.40 g of ZrN powder was then added to the solution and stirred for 4 hours to allow the inorganic salts to mix and absorb into the zirconium nitride. 13.5 g of 30% silica sol was then slowly added dropwise. After stirring for 1 hour, the suspension was transferred to a 70°C water bath and stirred for an additional 2 hours. 100 ml of 0.5 mol / L sodium hydroxide solution was slowly added dropwise to the suspension until the pH reached 7.0. The suspension was then aged in a 90°C water bath for 6 hours. The precipitate was filtered, washed to neutrality, and then dried in a 120°C oven for 10 hours. The resulting solid was calcined at 550°C for 6 hours to obtain the catalyst 55CuO-0.5Ag-4ZrN / 40.5SiO2. The resulting catalyst was compacted, crushed, and sieved into 20-40 mesh granules.

[0061] Example 615CuO-0.5Ag-4ZrN / 80.5SiO2

[0062] 4.56 g of copper nitrate trihydrate and 0.079 g of silver nitrate were weighed and dissolved in 50 ml of deionized water. The solution was stirred for 30 minutes until transparent. 0.40 g of ZrN powder was then added to the solution and stirred for 4 hours to allow the inorganic salts to mix and absorb into the zirconium nitride. 26.83 g of 30% silica sol was then slowly added dropwise. After stirring for 1 hour, the suspension was transferred to a 70°C water bath and stirred for an additional 2 hours. 100 ml of 0.5 mol / L sodium hydroxide solution was slowly added dropwise to the suspension until the pH reached 7.1. The suspension was then aged in a 90°C water bath for 6 hours. The precipitate was filtered, washed to neutrality, and then dried in a 120°C oven for 10 hours. The resulting solid was calcined at 550°C for 6 hours to obtain the catalyst 15CuO-0.5Ag-4ZrN / 80.5SiO2. The resulting catalyst was compacted and sieved into 20-40 mesh granules.

[0063] Catalyst evaluation

[0064] The performance of the prepared catalyst was evaluated in a high-pressure fixed-bed reactor using a methanol solution of methyl 3-hydroxypropionate as the reactant. The catalyst loading was 20.0 ml. The catalyst was reduced with hydrogen before feeding under the following reduction conditions: temperature 320°C, pressure 6 MPa, hydrogen flow rate 100 ml / min, and reaction time 5 h. The reaction conditions were: methyl 3-hydroxypropionate diluted with methanol to a mass concentration of 10%, temperature 160°C, pressure 6 MPa, and feed space velocity 0.3 h / min. -1 , hydrogen ester molar ratio 27.

[0065] After the reaction temperature stabilized for 5 hours, the product from the condensate tank after the reactor was collected. The raw materials and hydrogenated products were quantitatively and qualitatively analyzed using a GC-MC coupled instrument. The conversion rate of methyl 3-hydroxypropionate hydrogenation reaction and the selectivity of 1,3-propylene glycol were calculated. The calculation formula is as follows. The reaction results are shown in Table 1:

[0066]

[0067] .

[0068] Table 1

[0069]

[0070] As shown in Table 1, by comparing Examples 1 and 4 with Comparative Example 1, it can be seen that zirconium nitride with different crystal structures has good electronic conductivity, which is beneficial to maintaining the formed Cu 0 / Cu + The active valence state of the catalyst is increased, thereby improving the adsorption of the ester group on the catalyst, thereby improving the hydrogenation conversion rate of methyl 3-hydroxypropionate and the selectivity of 1,3-propylene glycol.

[0071] By comparing Examples 1-3 with Comparative Example 2, it can be seen that the addition of Ag, Pt, and Au metals can promote the reduction of copper oxide, thereby improving the ability of the catalyst to activate hydrogen and enhancing the catalyst activity.

[0072] By comparing Example 1 with Comparative Example 3, it can be seen that compared with the composite support impregnation method, the particle size of the active phase precursor CuO of the 35CuO-0.5Ag-4ZrN / 60.5SiO2 catalyst prepared by the precipitation method is smaller, and the hydrogenation conversion rate of 3-hydroxypropionic acid methyl ester and the selectivity of 1,3-propylene glycol are higher.

[0073] By comparing Example 1 with Comparative Examples 4 and 5, it can be seen that under the modification of precious metals Ag, Au, and Pt, zirconium nitride is more likely to conduct electrons than zirconium oxide and zirconium phosphate, thereby being more stable in Cu 0 / Cu + Active phase, improves 1,3-propylene glycol selectivity.

[0074] A comparison of Examples 1, 5, and 6 shows that CuO, zirconium nitride, and hydrogenation activator in the 3-hydroxypropionic acid methyl ester hydrogenation catalyst have a high degree of interaction, and the ratio of the three components significantly affects the conversion rate of 3-hydroxypropionic acid methyl ester and the improvement of 1,3-propylene glycol selectivity. Among them, the catalytic effect of 35CuO-0.5Ag-4ZrN / 60.5SiO2 is the best.

[0075] The above description is only a preferred embodiment of the present invention. All equivalent changes and modifications made according to the scope of the patent application of the present invention should fall within the scope of the present invention.

Claims

1. A highly selective catalyst for hydrogenating methyl 3-hydroxypropionate to 1,3-propylene glycol, characterized in that: Includes the following components: (a) Main component CuO; (b) electronic auxiliary agent zirconium nitride; (c) hydrogenation activating agent; (d) carrier and pore-enlarging agent SiO2; The zirconium nitride has a crystal structure of ZrN or Zr3N4; The hydrogenation active agent is one or more of Ag, Pt, and Au; Specifically, by weight percentage, the contents of each component in the catalyst are CuO 35%, Ag 0.5%, ZrN 4%, SiO2 60.5%, or CuO 35%, Pt 0.3%, ZrN 4%, SiO2 60.7%, or CuO 35%, Au 0.2%, ZrN 4%, SiO2 60.8%, or CuO 35%, Ag 0.5%, Zr3N4 4%, SiO2 60.7%, or CuO 55%, Ag 0.5%, ZrN 4%, SiO2 40.5%, or CuO 15%, Ag 0.5%, ZrN 4%, SiO2 80.5%.

2. A method for preparing the catalyst for hydrogenating methyl 3-hydroxypropionate to 1,3-propylene glycol with high selectivity as claimed in claim 1, characterized in that: The steps include: (1) Dissolve the CuO precursor and the hydrogenation active agent precursor in deionized water and stir for 30 minutes to obtain a transparent solution; (2) adding an electronic auxiliary agent to the transparent solution obtained in step (1) and stirring thoroughly for 4 hours; (3) Then, silica sol was slowly added dropwise to the mixed solution obtained in step (2), stirred thoroughly for 1 hour, and then transferred to a 70°C water bath and stirred for another 2 hours; (4) Slowly add 0.5 mol / L sodium hydroxide solution to the suspension formed in step (3) until the pH is 6.5-8.0, and then precipitate and age in a water bath at 70-90 °C for 4-12 hours; (5) The precipitate obtained in step (4) is filtered and washed until neutral, and then dried in an oven at 80-150°C for 4-40 hours; (6) calcining the dried solid obtained in step (5) at 300-750°C for 4-24 hours to obtain the catalyst.

3. The preparation method according to claim 2, characterized in that The precursor of CuO in step (1) is one or more of copper nitrate, copper sulfate, copper acetate and copper chloride.

4. The preparation method according to claim 2, characterized in that The precursor of the hydrogenation active agent in step (1) is one or more of nitrate, hydrochloride and acetate.

5. The preparation method according to claim 2, characterized in that The silica sol in step (3) is one of acidic silica sol, neutral silica sol and alkaline silica sol.

6. Use of the catalyst according to claim 1 in hydrogenating methyl 3-hydroxypropionate to produce 1,3-propylene glycol.

Images