In this study, a radio‐frequency plasma system was used to decompose a dichloromethane (CH2Cl2) containing gas. Analyses of the reactants and final products were conducted by using Fourier Transform Infrared Spectroscopy. Then, the effects of plasma operation‐parameters, including the gas flow rate, the feeding CH2Cl2 concentration, the equivalence ratio ϕ ( = stoichiometric O2 needed/actual O2 used) and the input power wattage, for CH2Cl2 decomposition and for the fraction of total carbon input converted into CO2 and CO were investigated. Mole fraction profiles for each experimental condition were determined for the reactants (CH2Cl2 and O2) and for CO, CO2, H2O, HCl, CHCl3, CCl4, COCl2, C2HCl3 and C2Cl4. In addition, the possible reaction pathways were built up and discussed.

A radio frequency (RF) plasma system has been used to decompose 1,2-dichloroethane (DCE). Final products were identified by a Fourier transform infrared (FTIR) spectrometer. The main products of DCE decomposition in O 2 /Ar plasma were CO 2 , CO, and HCl. Other minor chlorinated products were CCl 4 , C 2 HCl 3 , C 2 H 3 Cl, C 2 Cl 4 , CHCl 3 , C 2 HCl 5 , and COCl 2 . Nonchlorinated products were C 2 H 2 , C 2 H 4 , C 2 H 6 , and HCOOH. The plasma reactor with a brass electrode had a higher decomposition fraction of DCE [η C 2 H 4 Cl 2 , (C in − C out )/C in × 100%] than that obtained with other materials (Au, Ni, and Cr). Different electrode configurations (inner and outer) were also evaluated for the decomposition of DCE. Argon plus oxygen was found to be the most suitable carrier/auxiliary gas for DCE decomposition. In addition, operational parameters for DCE decomposition in RF plasma including concentration, operational pressure, and total gas flow rate were evaluated.

Application of radio-frequency (RF) plasma as an alternative technology for the decomposition of carbon dioxide with methane gas is demonstrated. The results of this study revealed that in plasma, the best CO 2 /CH 4 /Ar decomposition fraction of carbon dioxide was 60É0%, which occurs around 316¡C in the condition designed for 5% feeding concentration of 5% CO 2 , feeding concentration of 20 torr operation pressure, 100 sccm total gas CH 4 , Ñow rate and 90 watts input power wattage. The CH, and radicals CH 2 CH 3 obtained from the destruction of could result e †ectively in high decomposi-CH 4 tion of in the plasma reactor. The optimal mathematical models based on CO 2 the experimental data obtained were also developed and tested by means of sensitivity analysis, which shows that the input power wattage (W) was the most sensitive parameter for the decomposition. 1998 Society of Chemical CO 2 ( Industry J. Chem. T echnol. Biotechnol. 73, 432È442 (1998)