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J. Laimer, G. Misslinger, H. Störi:
"Time-resolved study of the conversion of chlorinated hydrocarbons in non-equilibrium hydrogen plasmas";
Vacuum, 71 (2003), 213 - 217.

The time evolution of the decomposition of chlorinated hydrocarbons in non-equilibrium hydrogen plasmas was investigated by experiment as well as by kinetic modelling. Singly chlorinated hydrocarbons (C₂H₃Cl, C₂H₅Cl) highly diluted in hydrogen were decomposed in an electrodeless pulsed r.f. discharge sustained in a quartz glass tube. The gasphase chemistry was also modelled by CHEMKIN computer code. In the model, the plasma was considered as weakly ionized so that the chemistry of neutral species plays the major role.
lt was found that the chlorinated hydrocarbons were decomposed very quickly to the main stable species HCI, CH₄ and C₂H₂. During the decomposition process, which lasts only a few milliseconds, a few chlorinated hydrocarbon radicals show up in the gas phase. Later on, the plasma is dominated by the radicals CH₃, Cl and H. CH₄, C₂H₂, and also smaller amounts Of C₂H₄ and C₂H₆ are in a quasi equilibrium after the decomposition process is completed. At steady state, the concentrations of the chlorinated hydrocarbons were close to the detection limit. Experiment and modelling are in good agreement.

Keywords: PIasma chemistry, Chlorinated hydrocarbons, Mass spectrometry; Kinetic modelling

http://aleph.ub.tuwien.ac.at/F?base=tuw01&func=find-c&ccl_term=AC04405850