Synthesis of Tetrafluoroethylene from the Pyrolysis of Chlorodifluoromethane in the Presence of Steam

과열 수증기를 이용한 클로로디플루오르메탄 열분해 반응에 의한 테트라플루오르에틸렌의 합성

  • 한명완 (충남대학교 화학공학과) ;
  • 김범식 (한국화학연구소 화학공정연구센터) ;
  • 김철웅 (한국화학연구소 화학공정연구센터) ;
  • 이정민 (한국화학연구소 화학공정연구센터)
  • Received : 1998.04.29
  • Accepted : 1998.12.28
  • Published : 1999.04.10

Abstract

The thermal pyrolysis of chlorodifluoromethane (R22) for producting tetrafluoroethylene (TFE) has been studied using the tubular reactor designed by the authors. The reaction temperature over $600{\sim}850^{\circ}C$, residence time over 0.005~0.6 sec, and steam/R22 ratio 3 to 30 were varied through experiments to analyze the effect of these variables on the conversion of R22 and selectivity for TFE. We have provided the guidelines for the optimal operation and design for the pyrolysis reactor. With increasing the dilution ratio, not only the conversion of R22 but also the selectivity for TFE increase. The optimum range of reaction temperature was $700{\sim}750^{\circ}C$ and the residence time 0.07~0.1 sec. In the kinetic study, first order rate equation was fitted well with the experimental data. This indicates that the main reaction step is a $CF_2$ generation from R22 pyrolysis. The range of activation energy for the rate constant was obtained 44.7~48 kcal/mol.

Keywords

Pyrolysis;Difluorochloromethane;Tetrafluoroethylene;Design;Operation

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