主催: The Society of Chemical Engineers, Japan
The present work is concerned with the destruction of air pollutant containing perfluorocompounds such as CHClF2, SF6 and CHF3 in a wire-in-tube pulsed corona reactor incorporated with in-situ absorption of halogenated gases formed. The influence of oxygen concentration and in-situ Ca(OH)2 absorption on the destruction of CHClF2, SF6 and CHF3 by non-thermal plasma was investigated. It was found that the destruction ratios of CHClF2, SF6 and CHF3 decreased with an increase in O2 concentration, but remained constant when the O2 concentration exceeded 10%. The major products detected from the destruction of CHClF2 in the presence of oxygen were HCl, Cl2, HF, F2, phosgene (COCl2) and CO2. The fractions of CO2 or SO2 in the destruction of CHClF2, SF6 and CHF3 increased dramatically with O2 concentration up to 2%, while the fractions increased slightly in the O2 concentration range of 2-20%. These behaviors in O2 atmosphere might have been due to the electrical properties of O2 in electrical discharge and to the production of O3 in the plasma system. When the Ca(OH)2 absorbent was placed on the corona reactor's wall, byproducts such as COCl2, HCl, HF, Cl2 and F2 were effectively scavenged during the destruction of CHClF2 in the presence of O2. It was considered that this was due to ability of Ca(OH)2 to absorb halogen radical or ion easily.
