Kinetic modeling of the decomposition of carbon tetrachloride in thermal plasma

Decomposition of carbon tetrachloride in a RF thermal plasma reactor was investigated in argon atmosphere. The net conversion of CCl4 and the main products of its decomposition were determined from the mass spectrometric analysis of outlet gases. Flow and temperature profiles in the reactor were calculated and concentration profiles of the species along the axis of the reactor were estimated using a newly developed chemical kinetic mechanism, containing 12 species and 34 reaction steps. The simulations indicated that all carbon tetrachloride decomposed within a few microseconds. However, CCl4 was partly recombined from its decomposition products. The calculations predicted 70% net conversion of CCl4, which was close to the experimentally determined value of 60%. A thermodynamic equilibrium model also simulated the decomposition. Results of the kinetic and thermodynamic simulations agreed well above 2000 K. However, below 2000K the thermodynamic equilibrium model gave wrong predictions. Therefore, application of detailed kinetic mechanisms is recommended for modeling CCl4 decomposition under thermal plasma conditions.