Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Synthetic process of 1,2 difluoro-1,2 dichloroethylene

A dichloroethylene and synthesis process technology, applied in the chemical industry, can solve the problems of difficulty in stirring, difficult to handle the bottom material, easy agglomeration, etc., and achieve the effects of reducing unsafe factors, no potential safety hazards, and not easy to agglomerate

Active Publication Date: 2016-07-27
许茂乾
View PDF2 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, there are some problems in the traditional F112 production process of 1,2-difluoro-1,2-dichloroethylene: 1) The traditional process is to put zinc powder and ethanol into the reactor at one time, and then add F112 dropwise at about 50°C reaction
However, when the activated zinc powder and a large amount of ethanol exist together, it is easy to agglomerate, which makes stirring very difficult, and the bottom material is also difficult to handle.
2) Activated zinc powder is relatively active, and reacts with water to generate hydrogen and a large amount of heat, so when mixed with ethanol, it will produce a great unsafe factor, which may easily cause ethanol combustion accidents

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Synthetic process of 1,2 difluoro-1,2 dichloroethylene

Examples

Experimental program
Comparison scheme
Effect test

specific Embodiment 1

[0021] Such as figure 1 Shown, a kind of 1,2 difluorine-1,2 dichloroethylene synthesis technique comprises the steps:

[0022] The first step, dechlorination reaction: using difluorotetrachloroethane (R112) as raw material and zinc powder to carry out dechlorination reaction in the presence of ethanol to generate difluorodichloroethylene, the 10% zinc powder is passed through dilute acid Carry out activation, the order number of zinc powder is 50 orders, and reaction equation is as follows:

[0023] ;

[0024] In the first step, the dechlorination reaction, a batch process is adopted, and 204 g of difluorotetrachloroethane is added into the reaction kettle after being measured, and stirring is started, and zinc powder is added in a 1:1 mol ratio, and the temperature is raised to 20 ° C, slowly Slowly add ethanol to react, the ratio of ethanol is 1:2mol, control the reflux ratio well, take out the fraction after passing the test to the fraction tank, and gradually raise the...

specific Embodiment 2

[0028] Such as figure 1 Shown, a kind of 1,2 difluorine-1,2 dichloroethylene synthesis technique comprises the steps:

[0029] The first step, dechlorination reaction: using difluorotetrachloroethane (R112) as raw material and zinc powder to carry out dechlorination reaction in the presence of ethanol to generate difluorodichloroethylene, the 10% zinc powder is passed through dilute acid Carry out activation, the order number of zinc powder is 100 orders, and reaction equation is as follows:

[0030] ;

[0031] In the first step, the dechlorination reaction, a batch process is adopted, and difluorotetrachloroethane is added into the reaction kettle after metering, stirring is started, zinc powder is added in a ratio of 1:2mol, and the temperature is raised to 20°C-70°C , slowly add ethanol dropwise to react, the ratio of ethanol is 1:6mol, control the reflux ratio well, take out the distillate after passing the test to the distillate tank, and gradually raise the temperatu...

specific Embodiment 3

[0035] Such as figure 1 Shown, a kind of 1,2 difluorine-1,2 dichloroethylene synthesis technique comprises the steps:

[0036] The first step, dechlorination reaction: using difluorotetrachloroethane (R112) as raw material and zinc powder to carry out dechlorination reaction in the presence of ethanol to generate difluorodichloroethylene, the 10% zinc powder is passed through dilute acid Carry out activation, the order number of zinc powder is 80 orders, and reaction equation is as follows:

[0037] ;

[0038] In the first step, the dechlorination reaction, a batch process is adopted, and difluorotetrachloroethane is added into the reaction kettle after metering, stirring is started, zinc powder is added in a ratio of 1:1.5mol, and the temperature is raised to 20°C-70°C. ℃, slowly add ethanol dropwise for reaction, the ratio of ethanol is 1:3mol, control the reflux ratio well, take out the distillate after passing it to the distillate tank, and gradually raise the temperat...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
particle size (mesh)aaaaaaaaaa
Login to View More

Abstract

The invention discloses a synthetic process of 1,2 difluoro-1,2 dichloroethylene. The synthetic process comprises the following steps: dechlorination reaction: causing tetra-chlorodifluoroethane (R112) which is used as a raw material and zinc powder to carry out a dechlorination reaction under a condition of the presence of ethyl alcohol to generate difluoro-dichloroethene; distillation operation: slowly adding sodium ethoxide into distillate at the temperature of 0-60DEG C to carry out reaction distillation operation, causing impurities 1.1 difluoro-2.2 dichloroethene and alcohol to react to generate ether in the presence of catalyst, then, carrying out distillation operation to remove impurity ether, and obtaining the finished product 1,2 difluoro-1,2 dichloroethylene. An intermittent process is adopted, the distillate is added into a reaction still by metering and is stirred, the catalyst is slowly added to carry out the reaction distillation operation, and fractionation is carried out to obtain the product, wherein the purity of the product is greater than or equal to 99.5%, and the yield of the product is greater than or equal to 95%.

Description

technical field [0001] The invention belongs to the field of chemical industry, and in particular relates to a synthesis process of 1,2-difluoro-1,2-dichloroethylene. Background technique [0002] 1,2 difluoro-1,2 dichloroethylene is a chemical intermediate with important industrial significance, and it is a necessary intermediate for the preparation of perfluoroalkyl (oxygen) vinyl ethers, such as perfluoromethyl vinyl ether (PMVE for short). body. PMVE is an important intermediate for the production of perfluoroethers, low-temperature resistant fluororubbers and modified fluoroplastics, as well as an important raw material for the synthesis of fluorine-containing pesticides and fluorine-containing pharmaceutical intermediates, with broad market prospects. [0003] Usually, 1,2-difluoro-1,2-dichloroethylene is prepared by dechlorinating 1,2-difluorotetrachloroethane (F112 for short) in a polar solvent under the catalysis of zinc powder. However, there are some problems in...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): C07C17/23C07C17/395C07C21/18
CPCC07C17/23C07C17/395C07C21/18
Inventor 吴盛均黄小磊徐斌斌张嘉鑫
Owner 许茂乾
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products