Synthesis and purification method of high-content chloroformic acid-2-ethyl hexyl ester

Abstract

The invention discloses a synthesis and purification method of high-content chloroformic acid-2-ethyl hexyl ester. A raw material iso-octanol is completely converted into chloroformic acid-2-ethyl hexyl ester and chloro-isooctane through a low-temperature and high-temperature two-step reaction, especially in a purification treatment stage, an entrainer is added, the chloro-isooctane is azeotrope and brought out at a relatively low temperature, chloroformic acid-2-ethyl hexyl ester is separated from chloro-isooctane through rectification, so that the purpose of purification is achieved, meanwhile, decomposition of chloroformic acid-2-ethyl hexyl ester can be avoided through low rectification temperature, and the product yield is guaranteed. The content of the chloroformic acid-2-ethyl hexyl ester treated by the method can be greater than 99%, and the impurity is composed of diisooctyl carbonate and a small amount of chloro-isooctane. The method has the characteristics of mild operation process conditions and simple equipment, meanwhile, the production of high-content chloroformic acid-2-ethyl hexyl ester has better market competitiveness, and the method has very good industrial application value.

Description

technical field

[0001] The application relates to the technical field of synthesis of 2-ethylhexyl chloroformate, in particular to a method for synthesizing and purifying high-content 2-ethylhexyl chloroformate. Background technique

[0002] 2-Ethylhexyl chloroformate is mainly used to prepare di(2-ethyl)hexyl peroxydicarbonate (EHP). EHP belongs to a highly active initiator and is often used as a polymerization initiator for general-purpose plastics and rubber materials. It can also be used in the production of bleaching agents, oxidation accelerators, flame retardants, etc. At present, the methods for producing 2-ethylhexyl chloroformate are divided into solid-light method and gas-light method. Most of industrialization adopts gas-light method, and the reaction mode is divided into batch reaction of kettle type and continuous reaction of tower type.

[0003] Patent CN101602667 introduces a preparation method of chloroformic acid-2-ethylhexyl ester, which uses solid phosge...

Examples

Embodiment 1

[0040] Put 20.0 mol of iso-octanol into the synthesis kettle, the ratio of phosgene:iso-octanol is 1:1.5, the reaction time is 4 hours, and the reaction temperature is 15°C. After the reaction in the low temperature section, the analytical content of the synthetic solution was 97.6% of 2-ethylhexyl chloroformate, 0.27% of diisooctyl carbonate, 1.16% of isooctyl alcohol, and 0.97% of chloroisooctane. Raise the temperature of the synthesis liquid in the low-temperature section to 40°C, and feed in phosgene. The molar ratio of phosgene to iso-octanol is 0.2:1, and the reaction time is 2 hours. After the reaction in the high temperature section, the analytical content of the synthetic solution was 98.2% of 2-ethylhexyl chloroformate, 0.29% of diisooctyl carbonate, 0.01% of isooctyl alcohol, and 1.5% of chloroisooctane. Light, acidity less than 0.1%.

[0041] The synthetic liquid of 2-ethylhexyl chloroformate extracted from the synthetic kettle is sent to the mixing kettle, and an...

Embodiment 2

[0043] Put 20.0 mol of isooctyl alcohol into the synthesis kettle, the ratio of phosgene:isooctanol is 1:1.3, the reaction time is 4 hours, and the reaction temperature is 15°C. After the reaction in the low temperature section, the analytical content of the synthetic liquid was 96.51% of 2-ethylhexyl chloroformate, 0.30% of di-isooctyl carbonate, 2.3% of isooctyl alcohol, and 0.89% of chloroisooctane. Raise the temperature of the synthesis liquid in the low-temperature section to 40°C, and feed in phosgene. The molar ratio of phosgene to iso-octanol is 0.2:1, and the reaction time is 2 hours. After the reaction in the high temperature section, the analytical content of the synthetic solution was 97.2% of 2-ethylhexyl chloroformate, 0.52% of diisooctyl carbonate, 0.005% of isooctyl alcohol, and 2.27% of chloroisooctane. Light, acidity less than 0.1%.

[0044] Send the synthesis liquid of 2-ethylhexyl chloroformate into the mixing tank, add an entrainer, the mass ratio of DMF:...

Embodiment 3

[0046] Put 20.0 mol of iso-octanol into the synthesis kettle, the ratio of phosgene:iso-octanol is 1:1.5, the reaction time is 6 hours, and the reaction temperature is 15°C. After the reaction in the low temperature section, the analytical content of the synthetic solution was 97.8% of 2-ethylhexyl chloroformate, 0.32% of diisooctyl carbonate, 0.93% of isooctyl alcohol, and 0.95% of chloroisooctane. Raise the temperature of the synthesis solution in the low-temperature section to 50°C, and feed in phosgene. The molar ratio of phosgene to iso-octanol is 0.2:1, and the reaction time is 2 hours. After the reaction in the high temperature section, the analytical content of the synthetic solution was 98.4% of 2-ethylhexyl chloroformate, 0.69% of diisooctyl carbonate, 0.01% of isooctyl alcohol, and 0.90% of chloroisooctane. Light, acidity less than 0.1%.

[0047] Send the synthesis liquid of 2-ethylhexyl chloroformate into the mixing tank, add an entrainer, the mass ratio of DMF:sy...

technical field

[0001] The application relates to the technical field of synthesis of 2-ethylhexyl chloroformate, in particular to a method for synthesizing and purifying high-content 2-ethylhexyl chloroformate. Background technique

[0002] 2-Ethylhexyl chloroformate is mainly used to prepare di(2-ethyl)hexyl peroxydicarbonate (EHP). EHP belongs to a highly active initiator and is often used as a polymerization initiator for general-purpose plastics and rubber materials. It can also be used in the production of bleaching agents, oxidation accelerators, flame retardants, etc. At present, the methods for producing 2-ethylhexyl chloroformate are divided into solid-light method and gas-light method. Most of industrialization adopts gas-light method, and the reaction mode is divided into batch reaction of kettle type and continuous reaction of tower type.

[0003] Patent CN101602667 introduces a preparation method of chloroformic acid-2-ethylhexyl ester, which uses solid phosge...

Examples

Embodiment 1

[0040] Put 20.0 mol of iso-octanol into the synthesis kettle, the ratio of phosgene:iso-octanol is 1:1.5, the reaction time is 4 hours, and the reaction temperature is 15°C. After the reaction in the low temperature section, the analytical content of the synthetic solution was 97.6% of 2-ethylhexyl chloroformate, 0.27% of diisooctyl carbonate, 1.16% of isooctyl alcohol, and 0.97% of chloroisooctane. Raise the temperature of the synthesis liquid in the low-temperature section to 40°C, and feed in phosgene. The molar ratio of phosgene to iso-octanol is 0.2:1, and the reaction time is 2 hours. After the reaction in the high temperature section, the analytical content of the synthetic solution was 98.2% of 2-ethylhexyl chloroformate, 0.29% of diisooctyl carbonate, 0.01% of isooctyl alcohol, and 1.5% of chloroisooctane. Light, acidity less than 0.1%.

[0041] The synthetic liquid of 2-ethylhexyl chloroformate extracted from the synthetic kettle is sent to the mixing kettle, and an...

Embodiment 2

[0043] Put 20.0 mol of isooctyl alcohol into the synthesis kettle, the ratio of phosgene:isooctanol is 1:1.3, the reaction time is 4 hours, and the reaction temperature is 15°C. After the reaction in the low temperature section, the analytical content of the synthetic liquid was 96.51% of 2-ethylhexyl chloroformate, 0.30% of di-isooctyl carbonate, 2.3% of isooctyl alcohol, and 0.89% of chloroisooctane. Raise the temperature of the synthesis liquid in the low-temperature section to 40°C, and feed in phosgene. The molar ratio of phosgene to iso-octanol is 0.2:1, and the reaction time is 2 hours. After the reaction in the high temperature section, the analytical content of the synthetic solution was 97.2% of 2-ethylhexyl chloroformate, 0.52% of diisooctyl carbonate, 0.005% of isooctyl alcohol, and 2.27% of chloroisooctane. Light, acidity less than 0.1%.

[0044] Send the synthesis liquid of 2-ethylhexyl chloroformate into the mixing tank, add an entrainer, the mass ratio of DMF:...

Embodiment 3

[0046] Put 20.0 mol of iso-octanol into the synthesis kettle, the ratio of phosgene:iso-octanol is 1:1.5, the reaction time is 6 hours, and the reaction temperature is 15°C. After the reaction in the low temperature section, the analytical content of the synthetic solution was 97.8% of 2-ethylhexyl chloroformate, 0.32% of diisooctyl carbonate, 0.93% of isooctyl alcohol, and 0.95% of chloroisooctane. Raise the temperature of the synthesis solution in the low-temperature section to 50°C, and feed in phosgene. The molar ratio of phosgene to iso-octanol is 0.2:1, and the reaction time is 2 hours. After the reaction in the high temperature section, the analytical content of the synthetic solution was 98.4% of 2-ethylhexyl chloroformate, 0.69% of diisooctyl carbonate, 0.01% of isooctyl alcohol, and 0.90% of chloroisooctane. Light, acidity less than 0.1%.

[0047] Send the synthesis liquid of 2-ethylhexyl chloroformate into the mixing tank, add an entrainer, the mass ratio of DMF:sy...

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