Study on photolytic and photocatalytic decontamination of air polluted by chemical warfare agents (CWAs)

Abstract

Photolytic and photocatalytic reactions of sarin (GB), soman (GD), sulfur mustard (HD), cyanogen chloride (CK) and perfluoroisobutylene (PFIB) vapors in air were carried out. It was shown that vapors of GB, GD, HD and PFIB could be efficiently eliminated by UV light from germicidal lamp through either photolysis or photocatalysis, but CK could hardly be done through photodegradation. It was demonstrated that GB, GD and HD might possibly undergo a photo-induced polymerization under UV light irradiation. Photocatalytic reaction would lead to a cleavage of these molecules into small inorganic compounds at TiO2 surface. The experimental results strongly suggested that both photolysis and photocatalysis of GB vapor at static conditions were kinetically slowed down and possibly limited by a low diffusion rate of GB molecule. It has been testified that the static photolysis approach could be applicable for decontamination of GB vapor in an indoor space. And that, a dynamic photocatalysis approach for decontamination of GB vapor was proved to be much more efficient than that through photolysis, and it was also considered to be feasible for decontamination of air polluted by GB vapor.