Pyrolysis of a mixture of trifluoromethane and tetrafluoroethylene to produce hexafluoropropylene

Authors
Moon, DJAhn, BS
Issue Date
2004-02
Publisher
SOC CHEMICAL ENG JAPAN
Citation
JOURNAL OF CHEMICAL ENGINEERING OF JAPAN, v.37, no.2, pp.318 - 325
Abstract
Pyrolysis of a mixture of trifluoromethane (CHF3, R23) and tetrafluoroethylene (CF2=CF2, TFE) to produce hexafluoropropylene (CF3CF=CF2, HFP) was investigated by the computer simulation and the pyrolysis. Experiments were carried out at the temperature ranges of 700-1000degreesC, molar ratios of R23/TFE=0.1-5.0 and contact times of 0.01-14.00 s. Product distributions for the pyrolysis of R23/TFE were estimated by the computer simulation and were confirmed by pyrolysis experiment. HFP and TFE were mainly produced with a small amount of by-products such as perfluoroisobutylene ((CF3)(2) C=CF2, PFiB), CF3CCCF3, C2F3H, CF3CHCF2 and CF3CF2CFCF2. It was proposed as a reaction mechanism that HFP might be produced from R23 through the following consecutive reaction: CHF3-->CF2=CF2-->C4F8-->CF3CF=CF2-->(CF3)(2)C=CF2, and that perfluoroisobutylene, the most harmful by-product, might be predominately formed by a reaction mechanism involving HFP and carbene [:CF2]. It was found that optimum conditions of the pyrolysis of R23/TFE mixtures experimentally determined were the molar ratio of R23/TFE=1-4, the reaction temperature of 850-900degreesC and the residence time of 0.5-2 seconds. The reaction temperature could be controlled by carefully utilizing the heat balance between an endothermic pyrolysis of R23 and an exothermic dimerization of TFE.
Keywords
CHLORODIFLUOROMETHANE; KINETICS; CHLORODIFLUOROMETHANE; KINETICS; pyrolysis; trifluoromethane (CHF3, R23); tetrafluoroethylene (CF2 = CF2, TFE); hexafluoropropylene (CF3CF=CF2, HFP)
ISSN
0021-9592
URI
https://pubs.kist.re.kr/handle/201004/137901
DOI
10.1252/jcej.37.318
Appears in Collections:
KIST Article > 2004
Files in This Item:
There are no files associated with this item.
Export
RIS (EndNote)
XLS (Excel)
XML

qrcode

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

BROWSE