Abatement of CF<sub>4</sub> and Associated Gas (NOx) with Combined Microwave Plasma and TiO<sub>2</sub> Catalyst

Abstract

The atmospheric-pressure microwave plasma can remove perfluorocompounds (PFCs) efficiently, which have long lifetime and serious global warming implications. However, associated gases such as NOx are produced in the abatement process of PFCs. In order to destroy PFCs and NOx pollutants, TiO2 catalyst is introduced into the abatement system. The effective TiO2 catalysts are prepared by a sol-gel method with the ratio of tetrabutyl titanate, ethanol, H2O and acetic acid = 1: 7: 1: 0.4. The abatement of CF4 and associated gas (NOx) is carried out with combined microwave plasma and TiO2 catalyst. The results show that the combined microwave plasma and catalyst abatement system can be successfully used to remove CF4 and NOx. The destruction and removal efficiency of CF4 and NOx were higher with the combined catalyst and plasma process than that with catalyst or plasma only.