INHIBITORY EFFECT OF THIOACETAMIDE ON CDS DISSOLUTION DURING PHOTOCATALYTIC OXIDATION OF 2,4-DICHLOROPHENOL

CdS dissolution and 2,4-dichlorophenol oxidation have been studied in the presence of thioacetamide during the photocatalytic reaction. It i s interesting to find that both the organic oxidation and the degree o f inhibition of CdS dissolution increase with increasing pH. In low pH range, the protonation of CdS surface is the major reason for CdS dis solution. Thioacetamide can inhibit the CdS dissolution to a certain d egree only at the beganing of the first 8 hours. At high pH range, the formation of Cd(OH)(2) determines the extent of CdS dissolution The i nhibition effect of thioacetamide on CdS has been minimized. The two p roposed mechanisms have been confirmed by quantitative analysis of bas e consumption during the processes. The optimal light intensity is 700 watts and temperature was found to be not an important factor in CdS dissolution