Photoproduction of hydroxyl radicals in aqueous solution with algae under high-pressure mercury lamp

Photoproduction of hydroxyl radicals ((OH)-O-.) could be induced in aqueous solution with algae (Nitzschia hantzschiana, etc.) and (or not) Fe3+ under high-pressure mercury lamp with an exposure time of 4 h. (OH)-O-. was determined by HPLC using benzene as a probe. The photoproduction of (OH)-O-. increased with increasing algae concentration. Fe3+ could enhance the photoproduction of (OH)-O-. in aqueous solution with algae. The results showed that the photoproduction of (OH)-O-. in algal solution with Fe3+ was greater than that in algal solution without Fe3+. The light intensity and pH affected the photoproduction of (OH)-O-. in aqueous solution with algae with/without Fe3+. The photoproduction of (OH)-O-. in aqueous solution with algae and Fe3+ under 250 W was greater than that under 125 W HPML. The photoproduction of (OH)-O-. in algal solution (pH ranged from 4.0 to 7.0) with (or not) Fe3+ at pH 4 was the greatest.