ADVANCED OXIDATION OF 4-CHLOROBENZALDEHYDE IN WATER BY UV-LIGHT, OZONATION AND COMBINATION OF BOTH METHODS

A comparative study was performed on the oxidizing degradation of 4-CL BzAl (used a model pollutant in water) by photolysis (lambda=253.7 nm) , ozonation and by combination of both methods. The resulting yields o f the degradation products (Cl- ions, aldehydes, carboxylic acids) wer e investigated as a function of UV-dose and action of ozone. The produ ct yields were determined by HPLC-analysis and their initial quantum y ields (Q(i)) were calculated. Based on the results, it was shown that the synergistic action of UV-irradiation and ozone leads to a more eff icient degradation of 4-CLBzAl. For explanation of the experimental re sults probable reaction mechanisms are suggested. (C) 1998 Elsevier Sc ience Ltd.