PHOTOELECTROCATALYTIC DEGRADATION OF DIURON ON TITANIA FILM

Abstract

Diuron is an herbicide generally used in Thailand. It is persistent and highly toxic. Thus, diuron has leaded to contamination problems in soil and water. In this study, photoelectrocatalysis (PEC), which is a coupling between photocatalysis and electrolysis, was used to degrade diuron in water, using titania as a photocatalyst. Titania was synthesized via sol-gel method and was coated on a titanium substrate that was used as the anode. On the other side of the system, a graphite plate was placed as the cathode. Box – Behnken design (BBD) was used to describe effect of applied voltage, pH, and chloride ion on the diuron degradation. As the results, efficiency of diuron degradation depends on pH, chloride ion and applied voltage, while apparent rate constant depends on pH and chloride ion.