Decomposition of PFCs by steam plasma at atmospheric pressure

摘要

Research to find out an optimum decomposition process for CF4, one of the most stable gases among PFCs, have conducted with the steam plasma processing which elevates decomposition rate for high reactivity of steam itself. Before performing experiment, thermodynamic equilibrium calculations are done for the condition of 1atm and 300K-5000K by a software program to check the concentration based on the composition at equilibrium. CF4 is injected at atmospheric pressure and analyzed quantitatively and qualitatively by using GC (Gas Chromatography). HF (hydrogen fluoride), a byproduct, is extracted from the device by a vacuum aspirator and changed into fluorite or others as it passes through scrubbers containing NaOH (sodium hydroxide) and CaCO3 (calcium carbonate). We Study the effects of reaction time, quenching condition, additive gas dilution. input power, and etc. on decomposition of CF4 and achieve more than 90% of the CF4 removal rate.