A production method of propylene glycol ether

Abstract

The present invention discloses a production method of propylene glycol ether. The method uses 3-chloro-1-propanol derived from 1,3-dichloropropene in the DD mixture by-produced from epichlorohydrin as a raw material, and continuously produces propylene glycol ether through gas-phase etherification reaction under the catalysis of a perovskite composite material, providing a new route for the production of propylene glycol ether. Moreover, this route has mild conditions, low cost, and advantages such as environmental protection and economy.

Description

Technical Field

[0001] The present invention relates to a production method of propylene glycol ether, specifically to a method for producing propylene glycol ether by using 3-chloro-1-propanol, a derivative of 1,3-dichloropropene in the by-product dichloro-diphenyl mixture (abbreviated as DD mixture) of epichlorohydrin, belonging to the technical field of by-product utilization in the chemical production process. Background Art

[0002] In the molecular structure of propylene glycol ether, there is an alkyl hydroxy ether bond, endowing it with the solvent characteristics of both alcohols and ethers; at the same time, due to the strong hydrogen bond of alcohol ethers, it becomes a strong coupler for various organic solvents and water; in addition, it has a mild odor, strong solubility, and a moderate evaporation rate. As a class of solvents with excellent properties, propylene glycol ethers are widely used in industries such as printing ink, industrial cleaning agents, coatings, copper-clad laminates, and printing and dyeing. Propylene glycol ethers with the same molecular weight have three isomers: 1-alkoxy-2-propanol, 2-alkoxy-1-propanol, and 3-alkoxy-1-propanol. Among them, 3-alkoxy-1-propanol has the best performance and a relatively higher price.

[0003] The mainstream propylene glycol ethers currently available on the market are prepared by reacting propylene oxide with alcohols. Patent CN101190878A uses propylene oxide and lower aliphatic alcohols as raw materials, and under the conditions of a reaction temperature of 100 - 300 °C, a reaction pressure of 1.0 - 3.0 MPa, a molar ratio of lower aliphatic alcohol / propylene oxide of 1 - 10:1, and a reaction space velocity of 1.0 - 4.0 h⁻¹, the raw materials are contacted with a catalyst loaded with active components such as niobium oxide to prepare propylene glycol ether; CN107400043A mentions using ionic liquid as a catalyst to synthesize propylene glycol ether with propylene oxide and alcohol as raw materials; CN100999448A mentions using ternary hydrotalcite as a catalyst to synthesize propylene glycol ether with propylene oxide and alcohol as raw materials under high pressure conditions; CN112979430A mentions using glycerol as a raw material and directly coupling glycerol hydrogenation and etherification by using a tandem catalytic reaction technology to produce propylene glycol ether products; CN1944365A discloses a one-pot method for directly generating propylene glycol ether from propylene, alcohol, and hydrogen peroxide. The principle of this method is to first oxidize propylene to propylene oxide by hydrogen peroxide, and then react propylene oxide with alcohol to produce propylene glycol ether.

[0004] CN112266320A uses 1,3-dichloropropanol as a raw material to obtain the important chemical raw material 1,3-propanediol through a four-step process of dehydration-hydrolysis-hydrogenation-hydrolysis. The specific process is as follows: 1,3-dichloropropanol undergoes a dehydration reaction with a dehydration catalyst to obtain 1,3-dichloropropene; then it is hydrolyzed at 50-150 °C for 2-10 h under the catalysis of carbonate to obtain 3-chloro-2-propen-1-ol; then 3-chloro-2-propen-1-ol undergoes a hydrogenation reaction with a hydrogenation catalyst at 20-100 °C and 1-10 MPa to obtain 3-chloropropanol; 3-chloropropanol undergoes a second hydrolysis reaction, and the hydrolysis conditions are carbonate catalysis, hydrolysis at 50-150 °C for 2-10 h, and finally 1,3-propanediol is obtained; in this invention, carbonate hydrolysis is used, the hydrolysis temperature is high, and there is a risk of generating carbon dioxide gas during the hydrolysis process, which is likely to cause abnormal pressure rise during the hydrolysis process.

[0005] There are few reported literatures on the etherification of alcohols with chlorides to prepare alcohol ethers, especially those with a propylene glycol ether structure. Japanese Patent JP2008044876 discloses the reaction of diols with chlorides under the catalysis of alkali metal hydroxides to prepare ethers. This patent uses alkali metal hydroxides as catalysts. The by-product HCl generated during the etherification reaction of chlorides with alcohols reacts with alkali metal hydroxides to form corresponding alkali metal chlorides. The catalyst is added according to the equivalent amount and cannot be recovered. There is a lot of waste brine, which is uneconomical.

[0006] JPH08113546 uses 3-chloro-1-propanol as a raw material and etherifies it with C1-C4 alcohols under the action of equivalent C1-C4 alcohol sodium or alcohol potassium. During the process, an equivalent amount of sodium chloride or potassium chloride is produced as a by-product. The catalyst cannot be recovered, and after the reaction, the generated chlorinated salt and the organic matter are a paste-like suspension. It is necessary to first filter the salt by suction and then further process and separate it to obtain 3-alkoxy propylene glycol ether. It is only suitable for small-scale production of pharmaceutical intermediates and is not suitable for large-scale industrial production.

[0007] A large amount of dichloropropene mixture (abbreviated as DD mixture) is produced as a by-product in the production process of epichlorohydrin. 65-85% of the components in the DD mixture are 1,3-dichloropropene. After purification and separation, about 90-140 Kg of 1,3-dichloropropene is produced as a by-product per ton of epichlorohydrin product; currently, it is mainly used for soil treatment to control nematodes, etc., resulting in serious environmental pollution and low application value.

[0008] A new technical solution is needed to achieve the efficient utilization of 1,3-dichloropropene. Summary of the Invention

[0009] The object of the present invention is to provide a production method of propylene glycol ether, specifically relating to a method for producing propylene glycol ether from 3-chloro-1-propanol, which is a derivative of 1,3-dichloropropene in the by-product DD mixture of an epichlorohydrin plant. Through the method of the present invention, the economic value of the by-products in the production process of epichlorohydrin can be effectively improved, and the problem of insufficient supply of high-quality propylene glycol ether in the existing market is also solved, providing a new way for the production of propylene glycol ether, turning waste into treasure and achieving green economy. This method has the advantages of simple operation and high product yield, and is suitable for industrial application.

[0010] In order to achieve the above-mentioned invention object, the technical scheme adopted by the present invention is as follows:

[0011] A production method of propylene glycol ether (3-alkoxy-1-propanol) includes the following steps: 3-chloro-1-propanol and an alcohol compound are subjected to a gas-phase reaction under the catalysis of a perovskite composite material to prepare propylene glycol ether.

[0012] In the present invention, the 3-chloro-1-propanol is prepared by hydrolysis and hydrogenation of 1,3-dichloropropene in the by-product DD mixture of epichlorohydrin.

[0013] In the present invention, the alcohol compound is selected from alcohols with 1 to 8 carbon atoms, preferably one or more of methanol, ethanol, propanol, isopropanol, butanol, 2-butanol, tert-butanol, isobutanol, pentanol, isopentanol, phenol, and benzyl alcohol.

[0014] In the present invention, the mass of the alcohol compound is 1 to 10 times that of 3-chloro-1-propanol, preferably 2 to 5 times.

[0015] In the present invention, the catalyst used in the gas-phase reaction is a perovskite composite material, such as a perovskite composite material catalyst containing metal elements of Cs, Pb, Ag, Bi, Co, Sb, and Cd. Suitable examples include but are not limited to Cs2PbI2Cl2 perovskite nanocrystals, multiferroic layered perovskite Bi5CoTi3O 15 , double perovskite nanocrystals Cs2AgBiI6, three-dimensional perovskite MAPbI3 nanomaterials, double perovskite nanocrystals Cs2AgBiBr6, (PA)2(MA)3Pb4I 13 perovskite nanomaterials, double perovskite nanocrystals Cs2AgBiCl6, double perovskite nanocrystals Cs2AgInxBiCl6, perovskite nanoparticles (CsPbBr3 NCs), Cs4CdSb2Cl 12 (CCSC) quadruple perovskite materials, Cs4CdBi2Cl 12 (CCBC) quadruple perovskite compounds, and one or more of CsPbI3 inorganic perovskites.

[0016] In the present invention, the temperature of the gas-phase reaction is 220 - 350 °C, preferably 240 - 300 °C.

[0017] In the present invention, the pressure of the gas-phase reaction is 0.01 - 0.5 MPaG, preferably 0.01 - 0.1 MPaG.

[0018] In the present invention, the feed space velocity of 3-chloro-1-propanol is 0.1 - 5 h -1 , preferably 0.1 - 0.5 h -1 .

[0019] In the present invention, the space velocity of the alcohol compound is 0.2 - 50 h -1 , preferably 0.2 - 2.5 h -1 .

[0020] Compared with the existing propylene glycol ether production technologies, in the present invention, 3-chloro-1-propanol derived from 1,3-dichloropropene in the by-product DD mixture produced during the production of epichlorohydrin is used as the raw material, and high-quality propylene glycol ether products are produced through gas-phase etherification. This turns the by-products of epichlorohydrin production into valuable resources, reduces the harm to the environment, enhances the economic value of the by-products, and at the same time changes the current situation of producing propylene glycol ether using propylene oxide or 1,3-propanediol as raw materials, providing a new technical route for the production of propylene glycol ether. This route has mild conditions and is green, showing certain prospects for industrialization.

[0021] Compared with the existing chlorination etherification technologies,

[0022] In the prior art, in the direct etherification process of 3-chloro-1-propanol and alcohol compounds, an alkaline catalyst is used. In the liquid-phase reaction, the by-produced hydrogen chloride cannot be removed in time, and it is easy to react with alkali metal hydroxides to form salts, resulting in the inability to recycle the catalyst, and the selectivity of the product is less than 90%. Although there is no literature report on the gas-phase process, the present inventor found that when using a sodium oxide-supported catalyst with strong alkalinity, although the generated hydrogen chloride can be removed in time during the reaction process to reduce the influence of hydrogen chloride on the catalyst, due to the too strong alkalinity, di-condensed and tri-condensed propylene glycol ether high-boiling substances are easily formed during the reaction process, covering the surface of the catalyst and sintering at high temperature, resulting in the inactivation of the catalyst and the inability to continuously produce. The present inventor surprisingly found that the B-site of the perovskite composite catalyst system is generally composed of variable-valence transition metal elements. On the unique cubic-phase quantum dot surface of the perovskite material, the B-site metal undergoes a valence change at high temperature. In order to maintain the electrical neutrality of the material, electron migration occurs inside the material, thereby forming electron-rich holes. These holes form covalent bond linkages with the reaction raw materials. After the reaction to remove hydrogen chloride is completed, according to the change in covalent bond energy, the reaction products are rapidly removed at high temperature, thereby achieving the formation of propylene glycol ether with high selectivity and effectively avoiding the occurrence of side reactions, making the selectivity of polypropylene glycol ether high-boiling substances <0.1%, and further solving the problem that the catalyst in the gas-phase process is covered by high-boiling substances and deactivated due to carbon deposition. Detailed implementation manners

[0023] The present invention is further described in detail in combination with the following embodiments, but the scope of the present invention is not limited to these embodiments.

[0024] Gas chromatographic analysis conditions for the product: Agilent gas chromatograph, RTX-WAX column, maintained at 50 °C for 5 min; increased to 80 °C at 10 °C / min and maintained for 5 min; increased to 100 °C at 10 °C / min and maintained for 5 min; increased to 160 °C at 10 °C / min and maintained for 15 min.

[0025] The specific surface area was measured using an F-sorb2400 specific surface area analyzer from KingAir Technology Co., Ltd.

[0026] Hydrogen chloride was analyzed using a metrohm tiamo 905 type acid-base titrator.

[0027] Preparation example (preparation of 3-chloro-1-propanol)

[0028] Add 1150 g of 1,3-dichloropropene to a 3 L three-necked flask, and dropwise add a mixture of 440 g of sodium hydroxide and 1400 g of water to the glass bottle over a period of 1.0 h. After the addition is completed, stir at 35 °C for 4 h, allow to stand for liquid separation, and obtain 944.2 g of 3-hydroxy-1-chloropropene with a yield of 98.5%.

[0029] 100 mL 3% Pd / SiO2 catalyst was installed in a 100 mL fixed bed reactor. Under the conditions of 3 MPa pressure and 70 °C, 3-hydroxy-1-chloropropene was heated to 7.5 h. -1 The gas enters the fixed bed reactor at an air velocity for hydrogenation reaction. The outlet is analyzed by gas phase detection. The conversion rate of 3-hydroxy-1-chloropropene is 96.5%, the selectivity of 3-chloro-1-propanol is 86.4%, and the selectivity of propanol is 13.6%. The hydrogenation reaction liquid is separated to obtain 3-chloro-1-propanol with a purity of 99.8%.

[0030] Example 1

[0031] 100 mL of multiferroic layered perovskite Bi5CoTi3O was installed in a 100 mL fixed bed reactor. 15 Catalyst (Xi'an Qiyue Biotechnology Co., Ltd.), at 0.04MPaG, 280℃, the feed space velocity of 3-chloro-1-propanol was 0.1h -1 , the feed space velocity of phenol is 0.3h -1 The mass composition of the reactor outlet was 67.75% phenol, 25.16% propylene glycol ether (3-phenoxy-1-propanol), 1.02% 3-chloro-1-propanol, 0.03% propylene glycol ether (3-phenoxy-1-propanol diacetate), and 6.04% hydrogen chloride. The conversion rate of 3-chloro-1-propanol was 93.88%, and the selectivity of propylene glycol ether (3-phenoxy-1-propanol) was 99.90%. The catalyst was removed after 20 hours of use for specific surface area analysis. The specific surface area of the catalyst before use was 1086 (m 2 / g), and the specific surface area after use is 1082 (m 2 / g).

[0032] Example 2

[0033] 100 mL of double perovskite nanocrystalline Cs2AgBiBr6 catalyst (Xi’an Qiyue Biotechnology Co., Ltd.) was installed in a 100 mL fixed-bed reactor at 0.05 MPaG, 260 °C, and a feed space velocity of 0.4 h of 3-chloro-1-propanol. -1 , the feed space velocity of tert-butyl alcohol is 1.5h -1 The mass composition at the reactor outlet was 63.35% tert-butyl alcohol, 27.79% propylene glycol tert-butyl ether (3-tert-butoxy-1-propanol), 1.16% 3-chloro-1-propanol, 0.02% propylene glycol ether (3-tert-butoxy-1-propanol diacetate), and 7.68% hydrogen chloride. The conversion rate of 3-chloro-1-propanol was 94.49%, and the selectivity of propylene glycol ether (3-tert-butoxy-1-propanol) was 99.92%. The catalyst was removed after 20 hours of use for specific surface area analysis. The specific surface area of the catalyst before use was 1137 (m 2 / g), and the specific surface area after use is 1132 (m 2 / g).

[0034] Example 3

[0035] 100 mL Cs4CdBi2Cl was installed in a 100 mL fixed bed reactor. 12 (CCBC) quadruple perovskite compound catalyst (Xi'an Qiyue Biotechnology Co., Ltd.), at 0.2MPaG, 245℃, the feed space velocity of 3-chloro-1-propanol was 0.5h -1 , the feed space velocity of methanol is 2.0h -1 The mass composition of the reactor outlet was methanol 73.51%, propylene glycol methyl ether (3-methoxy-1-propanol) 18.22%, 3-chloro-1-propanol 0.86%, dipropylene glycol ether (3-methoxy-1-propanol diacetate) 0.02%, and hydrogen chloride 7.39%. The conversion rate of 3-chloro-1-propanol was 95.70%, and the selectivity of propylene glycol ether (3-methoxy-1-propanol) was 99.94%. The catalyst was removed after 20 hours of use for specific surface area analysis. The specific surface area of the catalyst before use was 1217 (m 2 / g), and the specific surface area after use is 1213 (m 2 / g).

[0036] Comparative Example 1

[0037] 100 mL 10% Na2O / SiO2 catalyst (Qinzhou Yamei Chemical) was installed in a 100 mL fixed bed reactor. At 0.2 MPaG, 260 °C, the feed space velocity of 3-chloro-1-propanol was 0.5 h -1 , the feed space velocity of methanol is 2.0h -1 The mass composition at the reactor outlet was methanol 73.22%, propylene glycol methyl ether (3-methoxy-1-propanol) 12.37%, 3-chloro-1-propanol 0.01%, dipropylene glycol ether (dimethyl 3-methoxy-1-propanol) 5.87%, tripropylene glycol ether (trimethyl 3-methoxy-1-propanol) 0.81%, and hydrogen chloride 7.72%. The conversion rate of 3-chloro-1-propanol was 99.95%, and the selectivity of propylene glycol ether (3-methoxy-1-propanol) was 64.69%. The catalyst was removed after 20 hours of use for specific surface area analysis. The specific surface area of the catalyst before use was 897 (m 2 / g), and the specific surface area after use is 628 (m 2 / g).

[0038] Comparative Example 2

[0039] 100 mL Cs4CdBi2Cl was installed in a 100 mL fixed bed reactor. 12(CCBC) quadruple perovskite compound catalyst (Xi'an Qiyue Biotechnology Co., Ltd.), at 9.0MPaG, 245℃, and a feed space velocity of 0.5h-1 for 3-chloro-1-propanol -1 , the feed space velocity of methanol is 2.0h -1 The mass composition of the reactor outlet was methanol 75.78%, propylene glycol methyl ether 11.86%, 3-chloro-1-propanol 7.54%, propylene glycol ether 0.01%, and hydrogen chloride 4.81%. The conversion rate of 3-chloro-1-propanol was 62.30%, and the selectivity of propylene glycol ether was 99.95%. The catalyst was removed after 20 hours of use for specific surface area analysis. The specific surface area of the catalyst before use was 1217 (m 2 / g), and the specific surface area after use is 1183 (m 2 / g).

Claims

1. A production method of propylene glycol ether, comprising the following steps: 3-chloro-1-propanol and an alcohol compound are used to prepare propylene glycol ether through a gas-phase reaction under the catalysis of a perovskite composite material; the perovskite composite material is selected from one or more of Cs2PbI2Cl2 perovskite nanocrystals, multiferroic layered perovskite Bi5CoTi3O 15 , double perovskite nanocrystals Cs2AgBiI6, three-dimensional perovskite MAPbI3 nanomaterials, double perovskite nanocrystals Cs2AgBiBr6, (PA)2(MA)3Pb4I 13 perovskite nanomaterials, double perovskite nanocrystals Cs2AgBiCl6, double perovskite nanocrystals Cs2AgInxBiCl6, perovskite nanoparticles (CsPbBr3 NCs), Cs4CdSb2Cl 12 (CCSC) quadruple perovskite materials, Cs4CdBi2Cl 12 (CCBC) quadruple perovskite compounds, and one or more of CsPbI3 inorganic perovskites.

2. The method according to claim 1, wherein The alcohol compound is selected from C1-C8 alcohols.

3. The method according to claim 1, wherein The alcohol compound is selected from one or more of methanol, ethanol, propanol, isopropanol, butanol, 2-butanol, tert-butanol, isobutanol, pentanol, isopentanol, phenol, and benzyl alcohol.

4. The method according to claim 1, wherein The mass of the alcohol compound is 1-10 times that of 3-chloro-1-propanol.

5. The method according to claim 1, wherein The mass of the alcohol compound is 2-5 times that of 3-chloro-1-propanol.

6. The method according to claim 1, characterized in that The temperature of the gas-phase reaction is 220-350 °C; the pressure of the gas-phase reaction is 0.01-0.5 MPaG.

7. The method according to claim 1, characterized in that, The temperature of the gas-phase reaction is 240-300 °C; the pressure of the gas-phase reaction is 0.01-0.1 MPaG.

8. The method according to claim 1, wherein The feed space velocity of the 3-chloro-1-propanol is 0.1-5 h -1 .

9. The method according to claim 1, wherein The feed space velocity of the 3-chloro-1-propanol is 0.1-0.5 h -1 .

10. The method according to claim 1, wherein The 3-chloro-1-propanol is prepared by hydrolysis and hydrogenation of 1,3-dichloropropene.