Photocatalytic oxidation of propan-2-ol in the liquid phase by rutile

Abstract

The photocatalytic oxidation of liquid propan-2-ol to acetone has been investigated using irradiated suspensions of pure rutile. It is shown that ultraviolet radiation, rutile and a source of oxygen are all necessary for measurable reaction to occur at 310 K. The parameters controlling the photoactivity of pure rutile, together with effects of adding hydrogen peroxide, water or dissolved salts to the reaction mixture, have been investigated. Supporting measurements with doped rutile and less pure anatase have also been made.

The experimental results, which include values of the quantum yield, do not support a chain mechanism for acetone formation. Mechanisms are proposed, in which reactive species are formed by the surface trapping of both photoelectrons and photoholes.