A method for preparing 1,2-dichloroethane

Abstract

The present application discloses a method for preparing 1,2-dichloroethane, which comprises reacting a raw material containing ethylene glycol diacetate and hydrogen chloride in the presence of a catalyst to obtain the 1,2-dichloroethane. This method allows ethylene glycol diacetate to be efficiently converted into 1,2-dichloroethane, and the yield of 1,2-dichloroethane is very high.

Description

Technical Field

[0001] The present application relates to a method for preparing 1,2-dichloroethane, and belongs to the field of preparation and synthesis of 1,2-dichloroethane. Background Art

[0002] 1,2-Dichloroethane is a key raw material for the production of vinyl chloride monomer (VCM), which is primarily used in the production of polyvinyl chloride (PVC). It is also commonly used as a solvent in chemical processes. Currently, 1,2-Dichloroethane is primarily produced through the chlorination of ethylene (using petroleum as a raw material) or the oxychlorination of ethylene. However, due to my country's lack of petroleum, 1,2-Dichloroethane production has failed to meet domestic market demand.

[0003] Therefore, there is an urgent need to provide a new method for preparing 1,2-dichloroethane to meet the needs of the domestic market. Summary of the Invention

[0004] In order to overcome the deficiencies in the prior art, the present application provides a method for producing 1,2-dichloroethane from ethylene glycol diacetate.

[0005] The reaction of ethylene glycol diacetate and hydrogen chloride to produce 1,2-dichloroethane is a cascade reaction, and the reaction equation is as follows:

[0006] CH3COOCH2CH2OOCCH3+HCl→CH3COOCH2CH2Cl+CH3COOH (1)

[0007] CH3COOCH2CH2Cl+HCl→ClCH2CH2Cl+CH3COOH (2)

[0008] The method of the present application uses ethylene glycol diacetate and hydrogen chloride as the reaction raw materials. Ethylene glycol diacetate can be efficiently converted to obtain a high yield of 1,2-dichloroethane. Furthermore, the reaction between ethylene glycol diacetate and hydrogen chloride produces 1,2-dichloroethane and acetic acid. No water is produced during the reaction, significantly reducing the corrosiveness of the reaction system. Furthermore, the byproduct acetic acid can be recycled and reacted with ethylene glycol to produce the raw material ethylene glycol diacetate.

[0009] So far, the technology of converting ethylene glycol diacetate into 1,2-dichloroethane has not been reported.

[0010] The method for preparing 1,2-dichloroethane of the present application comprises reacting raw materials containing ethylene glycol diacetate and hydrogen chloride in the presence of a catalyst to obtain the 1,2-dichloroethane.

[0011] Optionally, the raw materials consist of ethylene glycol diacetate and hydrogen chloride.

[0012] Optionally, the raw material further includes a solvent; the solvent includes at least one of acetic acid, benzene, toluene, xylene, and 1,4-dioxane.

[0013] Optionally, the catalyst includes at least one of zinc chloride, chromium chloride, tin chloride, copper chloride and an ionic liquid.

[0014] Optionally, the ionic liquid is selected from at least one of pyridine hydrochloride, triethylamine hydrochloride, and imidazole hydrochloride.

[0015] Optionally, the imidazole hydrochloride includes at least one of imidazole hydrochloride, 1-methylimidazole hydrochloride, 1-ethyl-3-methylimidazole hydrochloride and 1-butyl-3-methylimidazole hydrochloride.

[0016] Optionally, the pyridine hydrochloride includes at least one of pyridine hydrochloride, 2-chloromethylpyridine hydrochloride, 1-butylpyridine hydrochloride and 1-butyl-4-methylpyridinium chloride hydrochloride.

[0017] Optionally, the mass ratio of ethylene glycol diacetate to hydrogen chloride is ethylene glycol diacetate:hydrogen chloride=1:0.5-20.

[0018] Optionally, the mass ratio of ethylene glycol diacetate to hydrogen chloride is ethylene glycol diacetate:hydrogen chloride=1:0.5-15.

[0019] Optionally, the mass ratio of ethylene glycol diacetate to hydrogen chloride is ethylene glycol diacetate:hydrogen chloride=1:4-12.

[0020] Optionally, the mass ratio of ethylene glycol diacetate to hydrogen chloride is selected from any value among 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, 1:11, 1:12, 1:13, 1:14, 1:15, 1:16, 1:17, 1:18, 1:19 and 1:20, or any range value therebetween.

[0021] Optionally, the mass ratio of ethylene glycol diacetate to the catalyst is ethylene glycol diacetate:catalyst=1:0.01-10.

[0022] Optionally, the mass ratio of ethylene glycol diacetate to the catalyst is ethylene glycol diacetate:catalyst=1:0.01-8.

[0023] Optionally, the mass ratio of ethylene glycol diacetate to the catalyst is ethylene glycol diacetate:catalyst=1:0.4-9.

[0024] Optionally, the mass ratio of ethylene glycol diacetate to the catalyst is selected from any value among 1:0.01, 1:0.05, 1:0.1, 1:0.2, 1:0.4, 1:0.5, 1:1, 1:1.2, 1:1.5, 1:2, 1:2.5, 1:3.0, 1:3.5, 1:4.0, 1:4.5, 1:5.0, 1:5.5, 1:6.0, 1:6.5, 1:7.0, 1:7.5, 1:8.0, 1:8.5, 1:9.0, 1:9.5 and 1:10.0, or any range value therebetween.

[0025] Optionally, the mass ratio of ethylene glycol diacetate to the solvent is: ethylene glycol diacetate:solvent=1:0-20.

[0026] Optionally, the mass ratio of ethylene glycol diacetate to the solvent is: ethylene glycol diacetate:solvent=1:0.5-1.5.

[0027] Optionally, the mass ratio of the ethylene glycol diacetate to the solvent is selected from any value among 1:0, 1:0.01, 1:0.05, 1:0.1, 1:0.2, 1:0.5, 1:1, 1:1.5, 1:2, 1:2.5, 1:3.0, 1:3.5, 1:4.0, 1:4.5, 1:5.0, 1:5.5, 1:6.0, 1:6.5, 1:7.0, 1:7.5, 1:8.0, 1:8.5, 1:9.0, 1:9.5, 1:10.0, 1:12.0, 1:13.0, 1:14.0, 1:15.0, 1:16.0, 1:17.0, 1:19.0 and 1:20.0, or any range value therebetween.

[0028] Optionally, the reaction conditions include: a pressure of 0.1 to 10 MPa.

[0029] Optionally, the reaction conditions include: a pressure of 0.1 to 1 MPa.

[0030] Optionally, the reaction conditions include: a pressure of 0.5 to 8 MPa.

[0031] Optionally, the reaction conditions include: a pressure of 1.5 to 6 MPa.

[0032] Optionally, the pressure is selected from any value among 0.1 MPa, 0.2 MPa, 0.5 MPa, 1.0 MPa, 1.5 MPa, 2.0 MPa, 3.0 MPa, 4.0 MPa, 5.0 MPa, 6.0 MPa, 7.0 MPa, 8.0 MPa, 9.0 MPa and 10.0 MPa, or a range value between any two of them.

[0033] Optionally, the reaction conditions include: a temperature of 50 to 220°C.

[0034] Optionally, the reaction conditions include: a temperature of 130-160°C.

[0035] Optionally, the reaction temperature is selected from any value among 50℃, 55℃, 60℃, 65℃, 70℃, 75℃, 80℃, 85℃, 90℃, 95℃, 100℃, 110℃, 120℃, 130℃, 140℃, 150℃, 160℃, 170℃, 180℃, 190℃, 200℃, 210℃ and 220℃, or any range between two of them.

[0036] Optionally, the reaction conditions include: time is 0.1 to 10 hours.

[0037] Optionally, the reaction conditions include: time is 0.1 to 9 hours.

[0038] Optionally, the time is selected from any value among 0.1h, 0.2h, 0.5h, 1.0h, 1.2h, 1.5h, 2.0h, 2.5h, 3.0h, 3.5h, 4.0h, 4.5h, 5.0h, 5.5h, 6.0h, 6.5h, 7.0h, 7.5h, 8.0h, 8.5h, 9.0h, 9.5h and 10.0h, or a range between any two of the values.

[0039] As an embodiment, the method for preparing 1,2-dichloroethane includes the following steps: adding the reaction raw materials ethylene glycol diacetate and hydrogen chloride, and optionally a specific solvent and a catalyst in a corrosion-resistant high-pressure reactor in a certain proportion, and then reacting at a certain pressure and a certain temperature for a certain time to obtain the reaction product 1,2-dichloroethane.

[0040] Optionally, the corrosion-resistant high-pressure reactor includes a corrosion-resistant kettle reactor and a corrosion-resistant tubular reactor, and the material thereof is selected from one of glass lining, porcelain enamel, tetrafluoroethylene lining, Hastelloy material and titanium material.

[0041] The beneficial effects of this application include:

[0042] 1) The present application provides a method for preparing 1,2-dichloroethane from ethylene glycol diacetate. Ethylene glycol diacetate can be efficiently converted into 1,2-dichloroethane, and the yield of 1,2-dichloroethane is very high.

[0043] 2) The method for preparing 1,2-dichloroethane provided in this application has great economic benefits. It not only develops downstream products of ethylene glycol, but also is closely connected with the vinyl chloride industry. DETAILED DESCRIPTION

[0044] The present application is described in detail below with reference to embodiments, but the present application is not limited to these embodiments.

[0045] The endpoints of the ranges disclosed in this application and any values are not limited to the exact ranges or values, and these ranges or values should be understood to include approximate ranges or values. For numerical ranges, the endpoints of each range and the individual point values can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0046] Unless otherwise specified, the raw materials in the examples of this application were purchased through commercial channels.

[0047] The analysis method in the examples of this application is as follows:

[0048] In the examples of the present application, the conversion of ethylene glycol diacetate was calculated by the following method:

[0049] The gas chromatographic peak area is obtained by configuring the ethylene glycol diacetate content in the standard solution, and the peak area is used as the abscissa and the concentration of ethylene glycol diacetate is used as the ordinate to obtain a standard curve; further, the concentration of ethylene glycol diacetate in the reaction solution after the reaction can be calculated, and the conversion rate of ethylene glycol diacetate can be calculated based on the concentration.

[0050] In the examples of the present application, the yield of 1,2-dichloroethane is calculated by the following method:

[0051] The gas chromatographic peak area is obtained by configuring the 1,2-dichloroethane content in the standard solution, and the peak area is used as the abscissa and the concentration of 1,2-dichloroethane is used as the ordinate to obtain a standard curve; further, the concentration of 1,2-dichloroethane in the reaction solution after the reaction can be calculated, and the yield of 1,2-dichloroethane can be calculated based on the concentration.

[0052] Example 1

[0053] 5g of ethylene glycol diacetate, 10g of hydrogen chloride, 50g of acetic acid as a solvent, and 0.05g of zinc chloride as a catalyst were added to a corrosion-resistant high-pressure reactor. The mixture was reacted at 0.5 MPa and 120°C for 4 hours. Gas chromatography analysis revealed a 97% conversion of ethylene glycol diacetate and a 91% yield of 1,2-dichloroethane.

[0054] In this embodiment, ethylene glycol diacetate:hydrogen chloride=1:2;

[0055] Ethylene glycol diacetate: catalyst = 1:0.01;

[0056] Ethylene glycol diacetate: solvent = 1:10.

[0057] Example 2

[0058] 5g of ethylene glycol diacetate, 100g of hydrogen chloride, 100g of acetic acid as a solvent, and 50g of 1-butyl-3-methylimidazole hydrochloride as a catalyst were added to a corrosion-resistant high-pressure reactor and reacted at 10 MPa and 50°C for 10 hours. Gas chromatography analysis revealed a 93% conversion of ethylene glycol diacetate and a 92% yield of 1,2-dichloroethane.

[0059] In this embodiment, ethylene glycol diacetate:hydrogen chloride=1:20;

[0060] Ethylene glycol diacetate: catalyst = 1:10;

[0061] Ethylene glycol diacetate: solvent = 1:20.

[0062] Example 3

[0063] 5g of ethylene glycol diacetate, 50g of hydrogen chloride, 50g of benzene as a solvent, and 6g of tin chloride as a catalyst were added to a corrosion-resistant high-pressure reactor. The mixture was reacted at 90°C at a pressure of 6 MPa for 6 hours. Gas chromatography analysis revealed a 95% conversion of ethylene glycol diacetate and a 93% yield of 1,2-dichloroethane.

[0064] In this embodiment, ethylene glycol diacetate:hydrogen chloride=1:10;

[0065] Ethylene glycol diacetate: catalyst = 1:1.2;

[0066] Ethylene glycol diacetate: solvent = 1:10.

[0067] Example 4

[0068] 5g of ethylene glycol diacetate, 30g of hydrogen chloride, 30g of 1,4-dioxane as a solvent, and 15g of 1-methylimidazole hydrochloride as a catalyst were added to a corrosion-resistant high-pressure reactor. The mixture was reacted at 3 MPa and 150°C for 2 hours. Gas chromatography analysis revealed a 97% conversion of ethylene glycol diacetate and a 95% yield of 1,2-dichloroethane.

[0069] In this embodiment, ethylene glycol diacetate:hydrogen chloride=1:6;

[0070] Ethylene glycol diacetate: catalyst = 1:3;

[0071] Ethylene glycol diacetate: solvent = 1:6.

[0072] Example 5

[0073] 5g of ethylene glycol diacetate, 2.5g of hydrogen chloride, and 20g of pyridine hydrochloride as a catalyst were added to a corrosion-resistant high-pressure reactor. The mixture was then reacted at 0.1 MPa and 200°C for 8 hours. Gas chromatography analysis revealed a 94% conversion of ethylene glycol diacetate and a 92% yield of 1,2-dichloroethane.

[0074] In this embodiment, ethylene glycol diacetate:hydrogen chloride=1:0.5;

[0075] Ethylene glycol diacetate: catalyst = 1:4;

[0076] Ethylene glycol diacetate: solvent = 1:0.

[0077] Example 6

[0078] 5g of ethylene glycol diacetate, 70g of hydrogen chloride, 60g of xylene as a solvent, and 30g of 1-butylpyridine hydrochloride as a catalyst were added to a corrosion-resistant high-pressure reactor. The mixture was reacted at 1 MPa and 170°C for 0.5 hours. Gas chromatography analysis revealed a 95% conversion of ethylene glycol diacetate and a 93% yield of 1,2-dichloroethane.

[0079] In this embodiment, ethylene glycol diacetate:hydrogen chloride=1:14;

[0080] Ethylene glycol diacetate: catalyst = 1:6;

[0081] Ethylene glycol diacetate: solvent = 1:12.

[0082] Example 7

[0083] 5g of ethylene glycol diacetate, 15g of hydrogen chloride, 10g of toluene as a solvent, and 2g of chromium chloride as a catalyst were added to a corrosion-resistant high-pressure reactor. The mixture was reacted at 2MPa and 220°C for 0.1 hour. Gas chromatography analysis revealed a 96% conversion of ethylene glycol diacetate and a 94% yield of 1,2-dichloroethane.

[0084] In this embodiment, ethylene glycol diacetate:hydrogen chloride=1:3;

[0085] Ethylene glycol diacetate: catalyst = 1:0.4;

[0086] Ethylene glycol diacetate: solvent = 1:2.

[0087] Example 8

[0088] 5g of ethylene glycol diacetate, 20g of hydrogen chloride, and 40g of 2-chloromethylpyridine hydrochloride as a catalyst were added to a corrosion-resistant high-pressure reactor and reacted at 1.5 MPa and 140°C for 4 hours. Gas chromatography analysis revealed a 100% conversion of ethylene glycol diacetate and a 99% yield of 1,2-dichloroethane.

[0089] In this embodiment, ethylene glycol diacetate:hydrogen chloride=1:4;

[0090] Ethylene glycol diacetate: catalyst = 1:8;

[0091] Ethylene glycol diacetate: solvent = 1:0.

[0092] Example 9

[0093] 5g of ethylene glycol diacetate, 25g of hydrogen chloride, 2.5g of xylene as a solvent, and 0.5g of copper chloride as a catalyst were added to a corrosion-resistant high-pressure reactor. The mixture was reacted at 3.5 MPa and 150°C for 4 hours. Gas chromatography analysis revealed a 100% conversion of ethylene glycol diacetate and a 97% yield of 1,2-dichloroethane.

[0094] In this embodiment, ethylene glycol diacetate:hydrogen chloride=1:5;

[0095] Ethylene glycol diacetate: catalyst = 1:0.1;

[0096] Ethylene glycol diacetate: solvent = 1:0.5.

[0097] Example 10

[0098] 5g of ethylene glycol diacetate, 40g of hydrogen chloride, 5g of benzene as a solvent, and 5g of triethylamine hydrochloride as a catalyst were added to a corrosion-resistant high-pressure reactor. The mixture was reacted at 5 MPa and 160°C for 2 hours. Gas chromatography analysis revealed a 100% conversion of ethylene glycol diacetate and a 96% yield of 1,2-dichloroethane.

[0099] In this embodiment, ethylene glycol diacetate:hydrogen chloride=1:8;

[0100] Ethylene glycol diacetate: catalyst = 1:1;

[0101] Ethylene glycol diacetate: solvent = 1:1.

[0102] Example 11

[0103] 5g of ethylene glycol diacetate, 65g of hydrogen chloride, 40g of 1,4-dioxane as a solvent, and 40g of 1-butyl-4-methylpyridinium chloride hydrochloride as a catalyst were added to a corrosion-resistant high-pressure reactor. The mixture was reacted at 7 MPa and 180°C for 1 hour. Gas chromatography analysis revealed a 100% conversion of ethylene glycol diacetate and a 97% yield of 1,2-dichloroethane.

[0104] In this embodiment, ethylene glycol diacetate:hydrogen chloride=1:13;

[0105] Ethylene glycol diacetate: catalyst = 1:8;

[0106] Ethylene glycol diacetate: solvent = 1:8.

[0107] Example 12

[0108] 5g of ethylene glycol diacetate, 75g of hydrogen chloride, and 30g of 1-ethyl-3-methylimidazole hydrochloride (catalyst) were added to a corrosion-resistant high-pressure reactor. The mixture was reacted at 8 MPa and 190°C for one hour. Gas chromatography analysis revealed a 100% conversion of ethylene glycol diacetate and a 98% yield of 1,2-dichloroethane.

[0109] In this embodiment, ethylene glycol diacetate:hydrogen chloride=1:15;

[0110] Ethylene glycol diacetate: catalyst = 1:6;

[0111] Ethylene glycol diacetate: solvent = 1:0.

[0112] Example 13

[0113] 5g of ethylene glycol diacetate, 90g of hydrogen chloride, 4g of acetic acid as a solvent, and 50g of imidazole hydrochloride as a catalyst were added to a corrosion-resistant high-pressure reactor. The mixture was reacted at 9 MPa and 220°C for 0.2 hours. Gas chromatography analysis revealed a 100% conversion of ethylene glycol diacetate and a 97% yield of 1,2-dichloroethane.

[0114] In this embodiment, ethylene glycol diacetate:hydrogen chloride=1:18;

[0115] Ethylene glycol diacetate: catalyst = 1:10;

[0116] Ethylene glycol diacetate: solvent = 1:0.8.

[0117] The above descriptions are merely a few embodiments of the present application and do not constitute any form of limitation to the present application. Although the present application discloses the preferred embodiments as above, they are not intended to limit the present application. Any technical personnel familiar with the present profession, without departing from the scope of the technical solution of the present application, using the technical content disclosed above to make slight changes or modifications are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A method for preparing 1,2-dichloroethane, characterized in that: The method comprises: reacting raw materials containing ethylene glycol diacetate and hydrogen chloride in the presence of a catalyst to obtain the 1,2-dichloroethane; The raw materials further include a solvent; the solvent includes at least one of acetic acid, benzene, toluene, xylene, and 1,4-dioxane; The catalyst comprises at least one of zinc chloride, chromium chloride, tin chloride, copper chloride and ionic liquid; The ionic liquid is selected from at least one of pyridine hydrochloride, triethylamine hydrochloride, and imidazole hydrochloride; The mass ratio of ethylene glycol diacetate to hydrogen chloride is ethylene glycol diacetate:hydrogen chloride=1:0.5-20; The mass ratio of ethylene glycol diacetate to the catalyst is ethylene glycol diacetate:catalyst=1:0.01-10; The mass ratio of ethylene glycol diacetate to solvent is ethylene glycol diacetate:solvent=1:0-20; The reaction conditions include: pressure of 0.1 to 10 MPa; temperature of 50 to 220° C.; and time of 0.1 to 10 hours.

2. The method according to claim 1, characterized in that The imidazole hydrochloride includes at least one of imidazole hydrochloride, 1-methylimidazole hydrochloride, 1-ethyl-3-methylimidazole hydrochloride and 1-butyl-3-methylimidazole hydrochloride; The pyridine hydrochloride includes at least one of pyridine hydrochloride, 2-chloromethylpyridine hydrochloride, 1-butylpyridine hydrochloride and 1-butyl-4-methylpyridinium chloride hydrochloride.

3. The method according to claim 1, characterized in that The mass ratio of the ethylene glycol diacetate to hydrogen chloride is ethylene glycol diacetate:hydrogen chloride=1:0.5-15.

4. The method according to claim 1, wherein The mass ratio of the ethylene glycol diacetate to hydrogen chloride is ethylene glycol diacetate:hydrogen chloride=1:4-12.

5. The method according to claim 1, wherein The mass ratio of the ethylene glycol diacetate to the catalyst is ethylene glycol diacetate:catalyst=1:0.01-8.

6. The method according to claim 1, characterized in that The mass ratio of the ethylene glycol diacetate to the catalyst is ethylene glycol diacetate:catalyst=1:0.4-9.

7. The method according to claim 1, characterized in that The mass ratio of the ethylene glycol diacetate to the solvent is ethylene glycol diacetate:solvent=1:0.5-1.

5.

8. The method according to claim 1, characterized in that The pressure is 0.1-1 MPa.

9. The method according to claim 1, characterized in that The pressure is 0.5-8 MPa.

10. The method according to claim 1, characterized in that The pressure is 1.5-6 MPa.

11. The method according to claim 1, wherein The temperature is 130-160°C.

12. The method according to claim 1, characterized in that The time is 0.1 to 9 hours.