Unlock instant, AI-driven research and patent intelligence for your innovation.

Method for recovering perfluoro propylene from technique of producing tetrafluoroethlene

A technology of perfluoropropylene and tetrafluoroethylene, applied in chemical instruments and methods, preparation of halogenated hydrocarbons, organic chemistry, etc., can solve problems such as difficult operation, low product quality, complicated process, etc., and reduce the amount of azeotrope , good extraction effect and simple operation

Active Publication Date: 2008-03-12
ZHONGHAO CHENGUANG RES INST OF CHEMICALINDUSTRY CO LTD
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This method uses two types of solvents, water and chloroform at the same time. Although the solvent is not expensive, it is also difficult to operate and the product quality is not high. In addition, in the second step of operation, since chloroform and water are high boiling substances, it is difficult to recycle chloroform. , cannot operate continuously, and also has the disadvantage of poor economy
[0008] In summary, prior art from containing perfluoropropene (C 3 f 6 ) and difluorochloromethane (CHClF 2 ) Perfluoropropene (C) is separated from the azeotrope 3 f 6 ) in the presence of perfluoropropene (C 3 f 6 ) The shortcomings of low product quality, complicated process, environmental pollution and high cost are obviously not suitable for industrial production.

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
  • Method for recovering perfluoro propylene from technique of producing tetrafluoroethlene
  • Method for recovering perfluoro propylene from technique of producing tetrafluoroethlene

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0030] Embodiment 1: the method for reclaiming perfluoropropene from tetrafluoroethylene production process, to mainly contain 5-8% perfluoropropene (C 3 f 6 ) and the corresponding component F 22 The mixture 1 of the mixture 1 is used as the starting material, and the 6th cut 7 containing perfluoropropene of higher concentration is separated therefrom, adopts the recovery equipment among Fig. Three series-connected dehydrogenation towers 17 and rectifying towers 18, of course, also include connected pipelines, reflux pipelines and corresponding valves, pumps and other conventional parts, the method is:

[0031] (1) Due to the low content of perfluoropropylene in the production system of tetrafluoroethylene, if the F containing perfluoropropylene 22 It is all used for extraction treatment, and the processing capacity is large, so it is not easy to recover perfluoropropylene, and it is difficult to recover F 22 , with a large amount of F 22Recycling back to the tetrafluoroe...

Embodiment 2

[0040] Embodiment 2: the processing capacity and composition of mixture 1 are unchanged, and ethanol is used to replace ethylene glycol, and all the other methods are the same as in embodiment 1, and the flow and composition of different fractions are obtained in the following table:

[0041] The flow rate and composition table of each fraction

[0042] project

mixture

Fraction 1

Fraction 2

Fraction 3

Fraction 4

Fraction 6

Mixture flow(kg / h)

140

115

25

18.4

6.6

5.4

Volume contains

quantity%

C 3 f 6

3

0.09

18.20

2.17

92

99.99

F 22

97

99.91

81.8

97.83

8

Quality contains

quantity%

C 3 f 6

5.1

0.16

27.84

3.7

95.22

F 22

94.9

99.84

72.16

96.3

4.78

Each component flow

Quantity(kg / h)

...

Embodiment 3

[0045] Embodiment 3: the processing capacity of mixture 1 is halved, and mixture 1 is substantially the same as embodiment 1, and extractant 8 is the same as embodiment 1, namely adopts ethylene glycol, and all the other methods are the same as embodiment 1, and the flow and composition of different fractions are obtained. The following table:

[0046] The flow rate and composition table of each fraction

[0047] project

mixture

Fraction 1

Fraction 2

Fraction 3

Fraction 4

Fraction 6

Mixture flow(kg / h)

70

54.16

15.84

12.20

3.64

3.1

Volume contains

quantity%

C 3 f 6

3.2

0.20

14.5

0.95

89

99.98

F 22

96.8

99.80

85.5

99.05

11

Quality contains

quantity%

C 3 f 6

5.42

0.35

22.73

1.64

93.35

F 22

94.58

99.65 ...

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

No PUM Login to View More

Abstract

This invention discloses a method for recovering hexafluoropropylene from the azeotrope of hexafluoropropylene and difluorochloromethane during tetrafluoroethylene production process. The method comprises primary distillation, extractive rectification and major rectification. The method has such advantages as high hexafluoropropylene recovery rate (higher than or equal to 97.8 vol. %), low solvent loss (lower than 1.1 kg / h), and high hexafluoropropylene quality (99.99 vol. %).

Description

technical field [0001] The present invention relates to a kind of recovery method of perfluoropropene, especially from containing perfluoropropene (C 3 f 6 ) and difluorochloromethane (CHClF 2 ) method for recovering perfluoropropylene in the tetrafluoroethylene production process of azeotrope. Background technique [0002] In difluorochloromethane (CHClF 2 , hereinafter collectively referred to as F 22 ) pyrolysis to generate tetrafluoroethylene (C 2 f 4 ) process, a certain amount of perfluoropropene (C 3 f 6 ), F 22 The pyrolysis cracking reaction equation is as follows: [0003] CHClF 2 →C 2 f 4 (volume ratio: 45-50%)+C 3 f 6 (volume ratio: 3-5%)+CHClF 2 (volume ratio: 40-45%) + others. [0004] The conversion rate of F22 in the cracking process is generally controlled at 20-80%. The unconverted F22 is recovered by rectification and then recycled for cracking. During the rectification process of recovering F22, because perfluoropropylene and F22 form a ho...

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 Patents(China)
IPC IPC(8): C07C17/386C07C19/08
Inventor 曾本忠朱德江
Owner ZHONGHAO CHENGUANG RES INST OF CHEMICALINDUSTRY CO LTD