Short Wavelength Ultraviolet Photolysis of Aqueous Carbon Tetrachloride

Abstract

ABSTRACT

A dielectric barrier discharge xenon-xenon excimer lamp, which emits with a maximum peak at 172 nm, was used to photolyze carbon tetrachloride (CCl₄) in air and in water. In air the primary removal mechanism for CCl₄ was found to be oxidation by atomic oxygen O(¹D). The O(¹D) radicals were formed by photolysis of O₂. Direct photolysis of CCl₄ and reaction with OH^., from the photodissociation of H₂O, were found to play minor roles. In aqueous phase photolysis, direct photolysis of CCl₄ was minimal and reactions with OH^. or H^. from the photolysis of H₂O were found to dominate the removal rate.

The energy costs of Vacuum Ultraviolet (VUV) photolysis as a treatment method are estimated for CCl₄ and chloroform (CHCl₃).