Method for selectively preparing 1, 3-propylene glycol and 1, 2-propylene glycol

Abstract

The invention provides a method for selectively preparing 1, 3-propylene glycol and 1, 2-propylene glycol, which comprises the following steps: sequentially carrying out hydroformylation reaction, aldehyde hydrogenation reaction and hydrolysis reaction on alkyl carboxylic acid vinyl ester serving as a raw material, and emphatically improving a composite catalyst for the hydroformylation reaction, thereby obtaining the 1, 3-propylene glycol and the 1, 2-propylene glycol. The composite catalyst is a copper / rhodium synergistic catalyst regulated and controlled by a phosphine ligand, so that alkyl carboxylic acid vinyl ester, carbon monoxide and hydrogen are subjected to hydroformylation reaction through regioselectivity under the synergistic effect of the copper catalyst, the rhodium catalyst and the phosphine ligand, and then 2-alkanoyloxy propionaldehyde or 3-alkanoyloxy propionaldehyde is generated in a high-selectivity mode. Further, 1, 3-propylene glycol and 1, 2-propylene glycol are selectively prepared; the method has the advantages of simple and easily available ligand, high reaction region selectivity, large-scale production and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of preparing propylene glycol from vinyl acetate, and particularly relates to a method for selectively preparing 1,3 - propanediol and 1,2 - propanediol. Background Art

[0002] 1,3 - Propanediol is an important chemical raw material, which can carry out esterification reactions with a large number of acid substances to synthesize a series of functional chemicals, and can also be used as a polymerization raw material to synthesize some functional materials. For example: 1,3 - propanediol and terephthalic acid are used to synthesize a new polyester material, namely polytrimethylene terephthalate (PTT). In addition, 1,3 - propanediol is also widely used in the synthesis of plasticizers, detergents, preservatives and emulsifiers. 1,2 - Propanediol has excellent hygroscopic and lubricating effects, and can be used as a good solvent for compounding agents, preservatives, ointments, pastes, vitamins and penicillin and other compounds or intermediates in the pharmaceutical and cosmetic industries. In addition, due to its low toxicity, it is often used as a solvent for flavors and pigments in the food industry.

[0003] Many processes for preparing 1,3 - propanediol have been reported. CN 116262683 A reports a method for preparing 1,3 - propanediol, using a nickel and cobalt dual - catalyst to synthesize 1,3 - propanediol, but the yield and selectivity of this synthesis method are relatively low. In addition, CN 105585447 A also reports a method for preparing 1,3 - propanediol, using lanthanide metal compounds and compounds of metals in IVA and VIB as catalysts, but the reaction pressure is relatively high, and the requirements for production equipment are relatively high, which is not suitable for industrial production.

[0004] Most of the production of 1,2 - propanediol uses petroleum and coal as raw materials, and the operation process is complicated, and a large amount of chemical pollution will be generated during the treatment process. Therefore, the research on the production technology of 1,2 - propanediol has become a hot topic in recent years. Armbruster et al. used a Pt / Al2O3 catalyst to synthesize 1,2 - propanediol by glycerol hydrogenolysis, but the selectivity was extremely low. Subsequently, D’Hondt et al. increased the selectivity of synthesizing 1,2 - propanediol to 64% with a Pt / NaY catalyst at 230°C. Mauriello et al. used isopropanol and glycerol as raw materials to produce 1,2 - propanediol with a selectivity of 55.9% under a Pd catalyst. Methods for highly selectively preparing 1,2 - propanediol are still rarely reported.

[0005] Currently, the preparation of 1,3-propanediol and 1,2-propanediol by sequentially performing regioselective hydroformylation, hydrogenation, and hydrolysis using vinyl acetate as a raw material has received extensive attention. Among them, the products 2-acetoxypropanal and 3-acetoxypropanal obtained by the hydroformylation of vinyl acetate are intermediates for the production of 1,2-propanediol and 1,3-propanediol. Therefore, the hydroformylation reaction of vinyl acetate is a very important reaction, and the selectivity of its catalyst is the key to the hydroformylation reaction. However, there have been no literature and patent reports on the method of simply regulating the ligand of the catalyst used in the hydroformylation reaction to highly selectively synthesize 1,3-propanediol and 1,2-propanediol. Summary of the Invention

[0006] In view of the problems existing in the prior art, the present invention provides a method for selectively preparing 1,3-propanediol and 1,2-propanediol. Using vinyl alkyl carboxylate as a raw material, it undergoes three steps: hydroformylation reaction, aldehyde group hydrogenation reaction, and hydrolysis reaction. The composite catalyst for the hydroformylation reaction is particularly improved. The composite catalyst is a copper / rhodium synergistic catalyst regulated by a phosphine ligand. Under the synergistic action of a copper catalyst, a rhodium catalyst, and a phosphine ligand, vinyl alkyl carboxylate undergoes regioselective hydroformylation reaction with carbon monoxide and hydrogen to highly selectively generate 2-alkanoyloxypropanal or 3-alkanoyloxypropanal, and then selectively prepare 1,3-propanediol and 1,2-propanediol. This method has the advantages of simple availability of the ligand, high regioselectivity of the reaction, and scalability of production.

[0007] To achieve this purpose, the present invention adopts the following technical solutions:

[0008] The purpose of the present invention is to provide a method for selectively preparing 1,3-propanediol and 1,2-propanediol, and the method includes the following steps:

[0009] The first step: Under the action of a composite catalyst, vinyl alkyl carboxylate undergoes regioselective hydroformylation reaction with carbon monoxide and hydrogen to selectively generate 2-alkanoyloxypropanal or 3-alkanoyloxypropanal;

[0010] Among them, the composite catalyst is a copper / rhodium synergistic catalyst regulated by a phosphine ligand; the composite catalyst for selectively generating 2-alkanoyloxypropanal includes: 4-(tetramethylammonium)phenyl diphenylphosphine as a ligand, copper trifluoromethanesulfonate, and tris(triphenylphosphine)rhodium carbonyl hydride; the composite catalyst for selectively generating 3-alkanoyloxypropanal includes: diphenyl-2-pyridylphosphine as a ligand, copper trifluoromethanesulfonate, and acetylacetonatotriphenylphosphine rhodium carbonyl.

[0011] Step 2: After purifying the crude product generated in Step 1, under the action of a hydrogenation catalyst, it undergoes an aldehyde group hydrogenation reaction with hydrogen to produce 2-acyloxypropanol or 3-acyloxypropanol;

[0012] Step 3: After purifying the crude product generated in Step 2, it undergoes a hydrolysis reaction under the action of a hydrolysis catalyst to produce 1,2-propanediol or 1,3-propanediol.

[0013] A large number of experimental studies by the inventors have shown that when using vinyl alkyl carboxylate as the raw material for hydroformylation reaction, the composite catalyst used is a copper / rhodium synergistic catalyst regulated by a phosphine ligand, which can highly selectively produce 2-acyloxypropanal or 3-acyloxypropanal; if it is used for highly selectively producing 2-acyloxypropanal, 4-(tetramethylammonium)phenyl diphenylphosphine is used as the ligand, copper trifluoromethanesulfonate is used as the copper catalyst, and tris(triphenylphosphine)rhodium hydride carbonyl HRh(CO)(PPh3)3 is used as the rhodium catalyst; if it is used for highly selectively producing 3-acyloxypropanal, diphenyl-2-pyridylphosphine is used as the ligand, copper trifluoromethanesulfonate is used as the copper catalyst, and rhodium acetylacetonate triphenylphosphine carbonyl Rh(CO)(acac)(PPh3) is used as the rhodium catalyst; if other copper catalysts such as copper chloride are used, the reaction yield will decrease significantly.

[0014] The method of the present invention uses vinyl alkyl carboxylate as the raw material and successively undergoes three steps: hydroformylation reaction, aldehyde group hydrogenation reaction and hydrolysis reaction. It focuses on improving the composite catalyst for the hydroformylation reaction. The composite catalyst is a copper / rhodium synergistic catalyst regulated by a phosphine ligand, enabling vinyl alkyl carboxylate to undergo a hydroformylation reaction with carbon monoxide and hydrogen through regioselectivity under the synergistic action of a copper catalyst, a rhodium catalyst and a phosphine ligand, thereby highly selectively producing 2-acyloxypropanal or 3-acyloxypropanal, and then selectively preparing 1,3-propanediol and 1,2-propanediol; this method has the advantages of simple and easily available ligands, high reaction regioselectivity and scalable production.

[0015] As a preferred technical solution of the present invention, in the first step, the composite catalyst for selectively generating 2-acyloxypropanal includes: compared with the molar amount of vinyl alkyl carboxylate, the molar addition amount of 4-(tetramethylammonium)phenyl diphenylphosphine is (0.001 - 0.3):1, such as 0.001:1, 0.005:1, 0.01:1, 0.05:1, 0.1:1, 0.2:1 or 0.3:1, etc., preferably (0.005 - 0.2):1; the molar addition amount of copper trifluoromethanesulfonate is (0.001 - 0.3):1, such as 0.001:1, 0.005:1, 0.01:1, 0.05:1, 0.1:1, 0.2:1 or 0.3:1, etc., preferably (0.005 - 0.2):1; the molar addition amount of tris(triphenylphosphine)rhodium carbonyl hydride is (0.001 - 0.3):1, such as 0.001:1, 0.002:1, 0.005:1, 0.01:1, 0.05:1, 0.1:1, 0.15:1, 0.2:1 or 0.3:1, etc., preferably (0.002 - 0.2):1.

[0016] As a preferred technical solution of the present invention, in the first step, the composite catalyst for selectively generating 3-acyloxypropanal includes: compared with the molar amount of vinyl alkyl carboxylate, the molar addition amount of diphenyl-2-pyridylphosphine is (0.001 - 0.3):1, such as 0.001:1, 0.005:1, 0.01:1, 0.05:1, 0.1:1, 0.2:1 or 0.3:1, etc., preferably (0.005 - 0.2):1; the molar addition amount of copper trifluoromethanesulfonate is (0.001 - 0.3):1, such as 0.001:1, 0.005:1, 0.01:1, 0.05:1, 0.1:1, 0.2:1 or 0.3:1, etc., preferably (0.005 - 0.2):1; the molar addition amount of acetylacetonatotriphenylphosphinerhodium carbonyl is (0.001 - 0.3):1, such as 0.001:1, 0.002:1, 0.005:1, 0.01:1, 0.05:1, 0.1:1, 0.15:1, 0.2:1 or 0.3:1, etc., preferably (0.002 - 0.2):1.

[0017] As a preferred technical solution of the present invention, in the first step, the vinyl alkyl carboxylate includes vinyl acetate or vinyl pivalate.

[0018] As a preferred technical solution of the present invention, in the first step, the hydroformylation reaction is carried out in an organic solvent, and the organic solvent includes any one or a combination of at least two of methanol, ethanol, isopropanol, ethyl acetate, dichloromethane or tetrahydrofuran.

[0019] As a preferred technical solution of the present invention, in the first-step hydroformylation reaction, the molar ratio of carbon monoxide to hydrogen is H2:CO = 1:(0.2 - 2), such as 1:0.2, 1:0.4, 1:0.6, 1:0.8, 1:1.0, 1:1.2, 1:1.4, 1:1.6, 1:1.8 or 1:2, etc., preferably H2:CO = 1:(0.7 - 1.5), the pressure range is 1 - 8 MPa, such as 1 MPa, 2 MPa, 3 MPa, 4 MPa, 5 MPa, 6 MPa, 7 MPa or 8 MPa, etc., preferably 2 - 5 MPa, the temperature range is 60 - 150 °C, such as 60 °C, 80 °C, 90 °C, 100 °C, 110 °C, 120 °C, 140 °C or 150 °C, etc., preferably 80 - 120 °C, the reaction time range is 6 - 16 h, such as 6 h, 8 h, 9 h, 10 h, 11 h, 12 h, 14 h or 16 h, etc., preferably 8 - 12 h.

[0020] As a preferred technical solution of the present invention, in the second step, the hydrogenation catalyst is a supported nickel catalyst; the mass addition amount of the hydrogenation catalyst is (0.005 - 0.4):1 compared to the mass of vinyl alkyl carboxylate, such as 0.005:1, 0.01:1, 0.05:1, 0.1:1, 0.15:1, 0.2:1, 0.3:1 or 0.4:1, etc., preferably (0.01 - 0.2):1.

[0021] As a preferred technical solution of the present invention, in the second-step aldehyde group hydrogenation reaction, the hydrogen pressure range is 0.1 - 5 MPa, such as 0.1 MPa, 0.5 MPa, 1 MPa, 1.5 MPa, 2 MPa, 2.5 MPa, 3 MPa, 4 MPa or 5 MPa, etc., preferably 0.5 - 3 MPa, the temperature range is 30 - 100 °C, such as 30 °C, 40 °C, 50 °C, 60 °C, 70 °C, 80 °C or 100 °C, etc., preferably 40 - 80 °C, the reaction time range is 2 - 16 h, such as 2 h, 4 h, 6 h, 8 h, 10 h, 12 h or 16 h, etc., preferably 4 - 12 h.

[0022] As a preferred technical solution of the present invention, in the third step, the hydrolysis catalyst is a base catalyst, and the base catalyst includes sodium hydroxide solution or potassium hydroxide solution.

[0023] As a preferred technical solution of the present invention, in the second step, the purification includes vacuum distillation; in the third step, the purification includes suction filtration and distillation carried out in sequence.

[0024] Compared with the prior art solutions, the present invention has at least the following beneficial effects:

[0025] (1) The method of the present invention uses vinyl alkyl carboxylate as a raw material, and successively undergoes three steps of hydroformylation reaction, aldehyde group hydrogenation reaction and hydrolysis reaction. The improvement focuses on the composite catalyst for the hydroformylation reaction. The composite catalyst is a copper / rhodium synergistic catalyst regulated by a phosphine ligand. Under the synergistic action of a copper catalyst, a rhodium catalyst and a phosphine ligand, vinyl alkyl carboxylate undergoes a hydroformylation reaction with carbon monoxide and hydrogen through regioselectivity, thereby highly selectively generating 2-acyloxypropanal or 3-acyloxypropanal, and then selectively preparing 1,3-propanediol and 1,2-propanediol;

[0026] (2) The method of the present invention has the advantages of simple and easily available ligands, high reaction regioselectivity and scalable production. Detailed implementation mode

[0027] To facilitate the understanding of the present invention, the following examples are listed. Those skilled in the art should understand that the examples are only for helping to understand the present invention and should not be regarded as specific limitations on the present invention.

[0028] Example 1

[0029] This example provides a method for selectively preparing 1,3-propanediol, and the method includes the following steps:

[0030] First step: Add 8.61 g of vinyl acetate, 0.36 g of copper trifluoromethanesulfonate, 0.25 g of rhodium acetylacetonate tricarbonyl triphenylphosphine Rh(CO)(acac)(PPh3), 0.26 g of diphenyl-2-pyridylphosphine and 10 mL of methanol into a 50 mL high-pressure reaction kettle. Install the high-pressure reaction kettle, purge the high-pressure reaction kettle with nitrogen 3 times, then purge with H2 / CO mixed gas 3 times, and finally fill with H2 / CO mixed gas at 2 MPa. The ratio of H2:CO in the H2 / CO mixed gas is 1:1. Heat up to 90 °C and carry out the hydroformylation reaction for 8 h;

[0031] Second step: After the crude product generated in the first step is purified by vacuum distillation, add it into a 50 mL high-pressure reaction kettle, then add 0.4 g of nickel-loaded (Ni-8076 from Shanghai Ruiyi Chemical Technology Co., Ltd.) and 10 mL of methanol. Install the high-pressure reaction kettle, purge the high-pressure reaction kettle with nitrogen 3 times, then purge with hydrogen 3 times, and finally fill with hydrogen at 1.0 MPa. Heat up to 50 °C and carry out the aldehyde group hydrogenation reaction for 8 h;

[0032] Third step: Filter the crude product of the second step, add 5 mL of 5 mol / L sodium hydroxide solution, react at room temperature for 0.5 h, and obtain 6.42 g of the main product 1,3-propanediol after purification by vacuum distillation. The yield is 84%.

[0033] Example 2

[0034] This embodiment provides a method for selectively preparing 1,3 - propanediol, and the method comprises the following steps:

[0035] First step: Add 8.61 g of vinyl acetate, 0.36 g of copper trifluoromethanesulfonate, 0.25 g of rhodium acetylacetonate carbonyl triphenylphosphine Rh(CO)(acac)(PPh3), 0.26 g of diphenyl - 2 - pyridylphosphine and 10 mL of methanol into a 50 mL high - pressure reactor. Install the high - pressure reactor, purge nitrogen in the high - pressure reactor 3 times, then purge the H2 / CO mixed gas 3 times, and finally charge the H2 / CO mixed gas at 2 MPa. In the H2 / CO mixed gas, H2:CO = 1:1. Heat up to 100 °C and carry out the hydroformylation reaction for 8 h;

[0036] Second step: After purifying and subjecting the crude product obtained in the first step to vacuum distillation, add it to a 50 mL high - pressure reactor, then add 0.4 g of supported nickel (Ni - 8076 from Shanghai Ruiyi Chemical Technology Co., Ltd.) and 10 mL of methanol. Install the high - pressure reactor, purge nitrogen in the high - pressure reactor 3 times, then purge hydrogen 3 times, and finally charge hydrogen at 1.0 MPa. Heat up to 50 °C and carry out the aldehyde hydrogenation reaction for 8 h;

[0037] Third step: Filter the crude product of the second step by suction, add 5 mL of 5 mol / L sodium hydroxide solution, react at room temperature for 0.5 h, and after purification and vacuum distillation, obtain 6.97 g of the main product 1,3 - propanediol, with a yield of 92%.

[0038] Example 3

[0039] This embodiment provides a method for selectively preparing 1,3 - propanediol, and the method comprises the following steps:

[0040] First step: Add 8.61 g of vinyl acetate, 0.36 g of copper trifluoromethanesulfonate, 0.25 g of rhodium acetylacetonate carbonyl triphenylphosphine Rh(CO)(acac)(PPh3), 0.26 g of diphenyl - 2 - pyridylphosphine and 10 mL of methanol into a 50 mL high - pressure reactor. Install the high - pressure reactor, purge nitrogen in the high - pressure reactor 3 times, then purge the H2 / CO mixed gas 3 times, and finally charge the H2 / CO mixed gas at 2 MPa. In the H2 / CO mixed gas, H2:CO = 1:1. Heat up to 90 °C and carry out the hydroformylation reaction for 12 h;

[0041] Second step: After purifying and subjecting the crude product obtained in the first step to vacuum distillation, add it to a 50 mL high - pressure reactor, then add 0.4 g of supported nickel (Ni - 8076 from Shanghai Ruiyi Chemical Technology Co., Ltd.) and 10 mL of methanol. Install the high - pressure reactor, purge nitrogen in the high - pressure reactor 3 times, then purge hydrogen 3 times, and finally charge hydrogen at 1.0 MPa. Heat up to 50 °C and carry out the aldehyde hydrogenation reaction for 10 h;

[0042] Step 3: Filter the crude product from Step 2 by suction, add 5 mL of 5 mol / L sodium hydroxide solution, react at room temperature for 0.5 h, and after purification by vacuum distillation, 7.46 g of the main product 1,3 - propanediol is obtained, with a yield of 98%.

[0043] Example 4

[0044] This example provides a method for selectively preparing 1,3 - propanediol, and the method comprises the following steps:

[0045] Step 1: Add 86.1 g of vinyl acetate, 1.8 g of copper trifluoromethanesulfonate, 1.3 g of rhodium carbonylacetylacetonatotriphenylphosphine Rh(CO)(acac)(PPh3), 1.3 g of diphenyl - 2 - pyridylphosphine, and 150 mL of methanol into a 500 mL high - pressure reactor. Install the high - pressure reactor, purge the reactor with nitrogen 3 times, then purge with the H2 / CO mixture 3 times, and finally charge the H2 / CO mixture at 2 MPa. In the H2 / CO mixture, H2:CO = 1:1. Heat up to 100 °C and carry out the hydroformylation reaction for 14 h;

[0046] Step 2: After purifying and vacuum - distilling the crude product generated in Step 1, add it into a 500 mL high - pressure reactor, then add 3 g of supported nickel (Ni - 8076 from Shanghai Ruiyi Chemical Technology Co., Ltd.) and 150 mL of methanol. Install the high - pressure reactor, purge the reactor with nitrogen 3 times, then purge with hydrogen 3 times, and finally charge hydrogen at 1.0 MPa. Heat up to 50 °C and carry out the aldehyde - group hydrogenation reaction for 12 h;

[0047] Step 3: Filter the crude product from Step 2 by suction, add 50 mL of 5 mol / L sodium hydroxide solution, react at room temperature for 1 h, and after purification by vacuum distillation, 72.36 g of the main product 1,3 - propanediol is obtained, with a yield of 95%.

[0048] Example 5

[0049] This example provides a method for selectively preparing 1,2 - propanediol, and the method comprises the following steps:

[0050] Step 1: Add 8.61 g of vinyl acetate, 0.36 g of copper trifluoromethanesulfonate, 0.46 g of hydridotris(triphenylphosphine)rhodium(I) HRh(CO)(PPh3)3, 0.31 g of 4 - (tetramethylammonium)phenyl diphenylphosphine, and 10 mL of methanol into a 50 mL high - pressure reactor. Install the high - pressure reactor, purge the reactor with nitrogen 3 times, then purge with the H2 / CO mixture 3 times, and finally charge the H2 / CO mixture at 2 MPa. In the H2 / CO mixture, H2:CO = 1:1. Heat up to 90 °C and carry out the hydroformylation reaction for 8 h;

[0051] Step 2: The crude product generated in the first step is purified by vacuum distillation and then added to a 50 mL high-pressure reactor. Then, 0.4 g of nickel-loaded (Ni-8076 from Shanghai Ruiyi Chemical Technology Co., Ltd.) and 10 mL of methanol are added. The high-pressure reactor is assembled, and nitrogen is flushed in and out of the high-pressure reactor 3 times, and then hydrogen is flushed in and out 3 times. Finally, hydrogen is charged to 1.0 MPa, the temperature is raised to 50 °C, and the aldehyde group hydrogenation reaction is carried out for 8 h;

[0052] Step 3: The crude product of the second step is filtered by suction, 5 mL of 5 mol / L sodium hydroxide solution is added, and the reaction is carried out at room temperature for 0.5 h. After purification by vacuum distillation, 6.88 g of the main product 1,2-propanediol is obtained, and the yield is 90%.

[0053] Example 6

[0054] This example provides a method for selectively preparing 1,2-propanediol, and the method includes the following steps:

[0055] Step 1: 8.61 g of vinyl acetate, 0.36 g of copper trifluoromethanesulfonate, 0.46 g of tris(triphenylphosphine)rhodium carbonyl hydride HRh(CO)(PPh3)3, 0.31 g of 4-(tetramethylammonium)phenyl diphenylphosphine, and 10 mL of methanol are added to a 50 mL high-pressure reactor. The high-pressure reactor is assembled, and nitrogen is flushed in and out of the high-pressure reactor 3 times, and then the H2 / CO mixed gas is flushed in and out 3 times. Finally, the H2 / CO mixed gas is charged to 2 MPa, and in the H2 / CO mixed gas, H2:CO = 1:1. The temperature is raised to 100 °C, and the hydroformylation reaction is carried out for 8 h;

[0056] Step 2: The crude product generated in the first step is purified by vacuum distillation and then added to a 50 mL high-pressure reactor. Then, 0.4 g of nickel-loaded (Ni-8076 from Shanghai Ruiyi Chemical Technology Co., Ltd.) and 10 mL of methanol are added. The high-pressure reactor is assembled, and nitrogen is flushed in and out of the high-pressure reactor 3 times, and then hydrogen is flushed in and out 3 times. Finally, hydrogen is charged to 1.0 MPa, the temperature is raised to 60 °C, and the aldehyde group hydrogenation reaction is carried out for 8 h;

[0057] Step 3: The crude product of the second step is filtered by suction, 5 mL of 5 mol / L sodium hydroxide solution is added, and the reaction is carried out at room temperature for 0.5 h. After purification by vacuum distillation, 7.31 g of the main product 1,2-propanediol is obtained, and the yield is 96%.

[0058] Example 7

[0059] This example provides a method for selectively preparing 1,2-propanediol, and the method includes the following steps:

[0060] Step 1: Add 8.61 g of vinyl acetate, 0.36 g of copper trifluoromethanesulfonate, 0.46 g of tris(triphenylphosphine)rhodium carbonyl hydride HRh(CO)(PPh3)3, 0.31 g of 4-(tetramethylammonium)phenyl diphenylphosphine, and 10 mL of methanol into a 50 mL high-pressure reactor. Install the high-pressure reactor, purge nitrogen into and out of the high-pressure reactor three times, then purge the H2 / CO mixture into and out of the reactor three times. Finally, charge the H2 / CO mixture at 2 MPa, with H2:CO = 1:1 in the H2 / CO mixture. Heat up to 100 °C and carry out the hydroformylation reaction for 12 h;

[0061] Step 2: After purifying and subjecting the crude product obtained in the first step to vacuum distillation, add it into a 50 mL high-pressure reactor. Then add 0.4 g of nickel supported (Ni-8076 from Shanghai Ruiyi Chemical Technology Co., Ltd.) and 10 mL of methanol. Install the high-pressure reactor, purge nitrogen into and out of the high-pressure reactor three times, then purge hydrogen into and out of the reactor three times. Finally, charge hydrogen at 1.0 MPa, heat up to 60 °C, and carry out the aldehyde group hydrogenation reaction for 10 h;

[0062] Step 3: Filter the crude product of the second step by suction, add 5 mL of 5 mol / L sodium hydroxide solution, react at room temperature for 0.5 h, and obtain 7.53 g of the main product 1,2-propanediol after purification and vacuum distillation, with a yield of 99%.

[0063] Example 8

[0064] This example provides a method for selectively preparing 1,2-propanediol, and the method includes the following steps:

[0065] Step 1: Add 86.1 g of vinyl acetate, 1.8 g of copper trifluoromethanesulfonate, 2.3 g of tris(triphenylphosphine)rhodium carbonyl hydride HRh(CO)(PPh3)3, 1.6 g of 4-(tetramethylammonium)phenyl diphenylphosphine, and 150 mL of methanol into a 500 mL high-pressure reactor. Install the high-pressure reactor, purge nitrogen into and out of the high-pressure reactor three times, then purge the H2 / CO mixture into and out of the reactor three times. Finally, charge the H2 / CO mixture at 2 MPa, with H2:CO = 1:1 in the H2 / CO mixture. Heat up to 100 °C and carry out the hydroformylation reaction for 14 h;

[0066] Step 2: After purifying and subjecting the crude product obtained in the first step to vacuum distillation, add it into a 500 mL high-pressure reactor. Then add 3 g of nickel supported (Ni-8076 from Shanghai Ruiyi Chemical Technology Co., Ltd.) and 150 mL of methanol. Install the high-pressure reactor, purge nitrogen into and out of the high-pressure reactor three times, then purge hydrogen into and out of the reactor three times. Finally, charge hydrogen at 1.0 MPa, heat up to 60 °C, and carry out the aldehyde group hydrogenation reaction for 12 h;

[0067] Step 3: Filter the crude product from Step 2 by suction filtration, add 50 mL of 5 mol / L sodium hydroxide solution, react at room temperature for 1 h, and obtain 74.94 g of the main product 1,2-propanediol after purification by vacuum distillation. Yield: 98%.

[0068] Example 9

[0069] This example provides a method for selectively preparing 1,3-propanediol. The method includes the following steps:

[0070] Step 1: Add 12.8 g of vinyl trimethylacetate, 0.36 g of copper trifluoromethanesulfonate, 0.25 g of rhodium acetylacetonate triphenylphosphine carbonyl Rh(CO)(acac)(PPh3), 0.26 g of diphenyl-2-pyridylphosphine, and 10 mL of methanol into a 50 mL high-pressure reactor. Install the high-pressure reactor, purge nitrogen into and out of the high-pressure reactor 3 times, then purge the H2 / CO mixed gas into and out of the reactor 3 times. Finally, charge the H2 / CO mixed gas at 2 MPa. The ratio of H2:CO in the H2 / CO mixed gas is 1:1. Heat up to 90 °C and carry out the hydroformylation reaction for 12 h;

[0071] Step 2: After purifying and vacuum distilling the crude product obtained in Step 1, add it to a 50 mL high-pressure reactor, then add 0.4 g of supported nickel (Ni-8076 from Shanghai Ruiyi Chemical Technology Co., Ltd.) and 10 mL of methanol. Install the high-pressure reactor, purge nitrogen into and out of the high-pressure reactor 3 times, then purge hydrogen into and out of the reactor 3 times. Finally, charge hydrogen at 1.0 MPa. Heat up to 50 °C and carry out the aldehyde group hydrogenation reaction for 10 h;

[0072] Step 3: Filter the crude product from Step 2 by suction filtration, add 5 mL of 5 mol / L sodium hydroxide solution, react at room temperature for 0.5 h, and obtain 7.56 g of the main product 1,3-propanediol after purification by vacuum distillation. Yield: 99%.

[0073] Example 10

[0074] This example provides a method for selectively preparing 1,2-propanediol. The method includes the following steps:

[0075] Step 1: Add 12.8 g of vinyl trimethylacetate, 0.36 g of copper trifluoromethanesulfonate, 0.46 g of tris(triphenylphosphine)rhodium hydride carbonyl HRh(CO)(PPh3)3, 0.31 g of 4-(tetramethylammonium)phenyl diphenylphosphine, and 10 mL of methanol into a 50 mL high-pressure reactor. Install the high-pressure reactor, purge nitrogen into and out of the high-pressure reactor 3 times, then purge the H2 / CO mixed gas into and out of the reactor 3 times. Finally, charge the H2 / CO mixed gas at 2 MPa. The ratio of H2:CO in the H2 / CO mixed gas is 1:1. Heat up to 100 °C and carry out the hydroformylation reaction for 12 h;

[0076] Step 2: The crude product obtained in Step 1 is added to a 50 mL high-pressure reactor after purification by vacuum distillation. Then, 0.4 g of nickel-loaded catalyst (Ni-8076 from Shanghai Ruiyi Chemical Technology Co., Ltd.) and 10 mL of methanol are added. The high-pressure reactor is assembled, and nitrogen is purged and filled into the reactor 3 times, then hydrogen is purged and filled 3 times. Finally, hydrogen is filled to 1.0 MPa, and the temperature is raised to 60 °C for the aldehyde group hydrogenation reaction for 10 h.

[0077] Step 3: The crude product from Step 2 is filtered by suction, 5 mL of 5 mol / L sodium hydroxide solution is added, and the reaction is carried out at room temperature for 0.5 h. After purification by vacuum distillation, the main product 1,2-propanediol is obtained with a yield of 7.59 g and a yield > 99%.

[0078] Comparative Example 1

[0079] This comparative example provides a method for preparing 1,3-propanediol, and the method includes the following steps:

[0080] Step 1: 8.61 g of vinyl acetate, 0.36 g of copper trifluoromethanesulfonate, 0.25 g of rhodium acetylacetonate triphenylphosphine carbonyl Rh(CO)(acac)(PPh3), 0.31 g of 4-(tetramethylammonium)phenyl diphenylphosphine, and 10 mL of methanol are added to a 50 mL high-pressure reactor. The high-pressure reactor is assembled, and nitrogen is purged and filled into the reactor 3 times, then the H2 / CO mixed gas is purged and filled 3 times. Finally, the H2 / CO2 mixed gas is filled to 2 MPa, with H2:CO = 1:1 in the H2 / CO mixed gas. The temperature is raised to 90 °C for the hydroformylation reaction for 8 h.

[0081] Step 2: The crude product obtained in Step 1 is added to a 50 mL high-pressure reactor after purification by vacuum distillation. Then, 0.4 g of nickel-loaded catalyst (Ni-8076 from Shanghai Ruiyi Chemical Technology Co., Ltd.) and 10 mL of methanol are added. The high-pressure reactor is assembled, and nitrogen is purged and filled into the reactor 3 times, then hydrogen is purged and filled 3 times. Finally, hydrogen is filled to 1.0 MPa, and the temperature is raised to 50 °C for the aldehyde group hydrogenation reaction for 8 h.

[0082] Step 3: The crude product from Step 2 is filtered by suction, 5 mL of 5 mol / L sodium hydroxide solution is added, and the reaction is carried out at room temperature for 0.5 h. After purification by vacuum distillation, the main product 1,3-propanediol is obtained with a yield of 3.52 g and a yield of 46%. The by-product 1,2-propanediol is obtained with a yield of 3.18 g and a yield of 42%.

[0083] Comparative Example 2

[0084] This comparative example provides a method for preparing 1,2-propanediol, and the method includes the following steps:

[0085] Step 1: Add 8.61 g of vinyl acetate, 0.36 g of copper trifluoromethanesulfonate, 0.46 g of tris(triphenylphosphine)rhodium(I) carbonyl hydride HRh(CO)(PPh3)3, 0.26 g of diphenyl-2-pyridylphosphine, and 10 mL of methanol into a 50 mL high-pressure reactor. Install the high-pressure reactor, purge nitrogen into and out of the high-pressure reactor three times, then purge the H2 / CO mixed gas into and out of the reactor three times. Finally, charge the H2 / CO mixed gas at 2 MPa, with H2:CO = 1:1 in the H2 / CO mixed gas. Heat up to 90 °C and carry out the hydroformylation reaction for 8 h.

[0086] Step 2: After purifying and subjecting the crude product obtained in the first step to vacuum distillation, add it into a 50 mL high-pressure reactor. Then add 0.4 g of nickel supported (Ni-8076 from Shanghai Ruiyi Chemical Technology Co., Ltd.) and 10 mL of methanol. Install the high-pressure reactor, purge nitrogen into and out of the high-pressure reactor three times, then purge hydrogen into and out of the reactor three times. Finally, charge hydrogen at 1.0 MPa, heat up to 50 °C, and carry out the aldehyde hydrogenation reaction for 8 h.

[0087] Step 3: Filter the crude product from the second step by suction, add 5 mL of 5 mol / L sodium hydroxide solution, react at room temperature for 0.5 h, and after purification and vacuum distillation, obtain 4.04 g of the main product 1,2-propanediol, with a yield of 53%; obtain 2.11 g of the by-product 1,3-propanediol, with a yield of 28%.

[0088] Comparative Example 3

[0089] This comparative example provides a method for preparing 1,3-propanediol, and the method comprises the following steps:

[0090] Step 1: Add 8.61 g of vinyl acetate, 0.13 g of copper chloride, 0.25 g of rhodium(I) acetylacetonato carbonyltriphenylphosphine Rh(CO)(acac)(PPh3), 0.26 g of diphenyl-2-pyridylphosphine, and 10 mL of methanol into a 50 mL high-pressure reactor. Install the high-pressure reactor, purge nitrogen into and out of the high-pressure reactor three times, then purge the H2 / CO mixed gas into and out of the reactor three times. Finally, charge the H2 / CO mixed gas at 2 MPa, with H2:CO = 1:1 in the H2 / CO mixed gas. Heat up to 90 °C and carry out the hydroformylation reaction for 12 h.

[0091] Step 2: After purifying and subjecting the crude product obtained in the first step to vacuum distillation, add it into a 50 mL high-pressure reactor. Then add 0.4 g of nickel supported (Ni-8076 from Shanghai Ruiyi Chemical Technology Co., Ltd.) and 10 mL of methanol. Install the high-pressure reactor, purge nitrogen into and out of the high-pressure reactor three times, then purge hydrogen into and out of the reactor three times. Finally, charge hydrogen at 1.0 MPa, heat up to 50 °C, and carry out the aldehyde hydrogenation reaction for 10 h.

[0092] Step 3: Filter the crude product obtained in Step 2 by suction, add 5 mL of 5 mol / L sodium hydroxide solution, react at room temperature for 0.5 h, and obtain 5.24 g of the main product 1,3 - propanediol after purification by vacuum distillation. Yield: 69%.

[0093] Summarize the key data of the above - mentioned examples and comparative examples in Table 1.

[0094] Table 1

[0095]

[0096] In summary, the present invention provides a method for selectively preparing 1,3 - propanediol and 1,2 - propanediol. Using vinyl alkyl carboxylate as a raw material, it successively undergoes three steps: hydroformylation reaction, aldehyde group hydrogenation reaction, and hydrolysis reaction. The improvement focuses on the composite catalyst for the hydroformylation reaction. The composite catalyst is a copper / rhodium synergistic catalyst regulated by a phosphine ligand. Under the synergistic action of a copper catalyst, a rhodium catalyst, and a phosphine ligand, vinyl alkyl carboxylate undergoes a hydroformylation reaction with carbon monoxide and hydrogen through regioselectivity, thereby highly selectively generating 2 - alkanoyloxypropanal or 3 - alkanoyloxypropanal, and then selectively preparing 1,3 - propanediol and 1,2 - propanediol. This method has the advantages of simple and easily available ligands, high reaction regioselectivity, and scalability for production.

[0097] Specifically, for the hydroformylation reaction using vinyl alkyl carboxylate as a raw material, the composite catalyst used is a copper / rhodium synergistic catalyst regulated by a phosphine ligand, which can highly selectively generate 2 - alkanoyloxypropanal or 3 - alkanoyloxypropanal. If it is used to highly selectively generate 2 - alkanoyloxypropanal, 4 - (tetramethylammonium)phenyl diphenylphosphine is used as the ligand, copper trifluoromethanesulfonate is used as the copper catalyst, and tris(triphenylphosphine)rhodium hydride carbonyl HRh(CO)(PPh3)3 is used as the rhodium catalyst. If it is used to highly selectively generate 3 - alkanoyloxypropanal, diphenyl - 2 - pyridylphosphine is used as the ligand, copper trifluoromethanesulfonate is used as the copper catalyst, and rhodium acetylacetonate triphenylphosphine carbonyl Rh(CO)(acac)(PPh3) is used as the rhodium catalyst. If other copper catalysts, such as copper chloride, are used, the reaction yield will decrease significantly.

[0098] The present invention uses the above - mentioned examples to illustrate the detailed process equipment and process flow of the present invention. However, the present invention is not limited to the above - mentioned detailed process equipment and process flow, that is, it does not mean that the present invention must rely on the above - mentioned detailed process equipment and process flow to be implemented. Those skilled in the art should understand that any improvement to the present invention, equivalent replacement of each raw material of the products of the present invention, addition of auxiliary components, and selection of specific methods, etc., all fall within the protection scope and the disclosure scope of the present invention.

Claims

1. A method for selectively preparing 1,3-propanediol and 1,2-propanediol, characterized in that, The method includes the following steps: Step 1: Under the action of a composite catalyst, vinyl alkyl carboxylate undergoes a hydroformylation reaction with carbon monoxide and hydrogen through regioselectivity to selectively produce 2-alkanoyloxypropanal or 3-alkanoyloxypropanal; Among them, the composite catalyst is a copper / rhodium synergistic catalyst regulated by a phosphine ligand; the composite catalyst for selectively producing 2-alkanoyloxypropanal includes: 4-(tetramethylammonium)phenyl diphenylphosphine as a ligand, copper trifluoromethanesulfonate and tris(triphenylphosphine)rhodium hydride carbonyl; the composite catalyst for selectively producing 3-alkanoyloxypropanal includes: diphenyl-2-pyridylphosphine as a ligand, copper trifluoromethanesulfonate and acetylacetonatotriphenylphosphine rhodium carbonyl; Step 2: After purifying the crude product obtained in the first step, it undergoes an aldehyde group hydrogenation reaction with hydrogen under the action of a hydrogenation catalyst to produce 2-alkanoyloxypropanol or 3-alkanoyloxypropanol; Step 3: After purifying the crude product obtained in the second step, it undergoes a hydrolysis reaction under the action of a hydrolysis catalyst to produce 1,2-propanediol or 1,3-propanediol.

2. The method according to claim 1, characterized in that In the first step, the composite catalyst for selectively producing 2-alkanoyloxypropanal includes: compared with the molar amount of vinyl alkyl carboxylate, the molar addition amount of 4-(tetramethylammonium)phenyl diphenylphosphine is (0.001 - 0.3):1, the molar addition amount of copper trifluoromethanesulfonate is (0.001 - 0.3):1, and the molar addition amount of tris(triphenylphosphine)rhodium hydride carbonyl is (0.001 - 0.3):

1.

3. The method according to claim 1, wherein In the first step, the composite catalyst for selectively producing 3-alkanoyloxypropanal includes: compared with the molar amount of vinyl alkyl carboxylate, the molar addition amount of diphenyl-2-pyridylphosphine is (0.001 - 0.3):1, the molar addition amount of copper trifluoromethanesulfonate is (0.001 - 0.3):1, and the molar addition amount of acetylacetonatotriphenylphosphine rhodium carbonyl is (0.001 - 0.3):

1.

4. The method according to any one of claims 1-3, characterized in that, In the first step, the vinyl alkyl carboxylate includes vinyl acetate or vinyl trimethylacetate.

5. The method according to any one of claims 1-3, characterized in that, In the first step, the hydroformylation reaction is carried out in an organic solvent, and the organic solvent includes any one or a combination of at least two of methanol, ethanol, isopropanol, ethyl acetate, dichloromethane, or tetrahydrofuran.

6. The method according to any one of claims 1 to 3, characterized in that In the hydroformylation reaction of the first step, the molar ratio of hydrogen to carbon monoxide is H2:CO = 1:(0.2 - 2), the pressure range is 1 - 8 MPa, the temperature range is 60 - 150 °C, and the reaction time range is 6 - 16 h.

7. The method according to any one of claims 1 to 3, characterized in that, In the second step, the hydrogenation catalyst is a supported nickel catalyst; compared with the mass of vinyl alkyl carboxylate, the mass addition amount of the hydrogenation catalyst is (0.005 - 0.4):

1.

8. The method according to any one of claims 1 to 3, characterized in that, In the aldehyde group hydrogenation reaction of the second step, the hydrogen pressure range is 0.1 - 5 MPa, the temperature range is 30 - 100 °C, and the reaction time range is 2 - 16 h.

9. The method according to any one of claims 1 to 3, characterized in that In the third step, the hydrolysis catalyst is a base catalyst, and the base catalyst includes sodium hydroxide solution or potassium hydroxide solution.

10. The method according to any one of claims 1-3, characterized in that, In the second step, the purification includes vacuum distillation; in the third step, the purification includes suction filtration and distillation carried out successively.

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