Destruction of phenol aqueous solution by photocatalysis or direct photolysis

The photodegradation of phenol has been investigated under a high-pressure mercury lamp with a kind of jacket (glass or quartz) depending on used UV l ight range and a variety of experimental conditions: UV (lambda > 200 nm) w ith oxygen or with TiO2 and oxygen or with N-2; UV (lambda > 330 nm) with o xygen or with TiO2 and oxygen or with N-2. Photocatalysis and direct photol ysis of phenol have different reaction pathways. Direct photolysis of pheno l yielded a brown-yellow complex organic polymer in both aerobic and anaero bic environments. The polymer cannot be mineralized in an anaerobic environ ment. The effects of catalyst amount and oxygen concentration in the reacti on atmosphere on the destruction of phenol were studied. The results prove that an appropriate catalyst amount can avoid direct photolysis and increas e the mineralization rate of phenol. (C) 2000 Elsevier Science Ltd. All rig hts reserved.