Photochemical oxidation of chlorinated phenols in comparison with electro-oxidation

Abstract

Photooxidation of chlorophenols was studied and the results were analyzed. It has been found that 4-chlorophenol is oxidized faster than other chlorinated phenols, indicating that higher chlorinated phenols are hard to decompose and the order of the decomposition was as follows: 4-CP > 2,4-DCP > 2,4,6-TCP > PCP.

Substituent effect on nano TiO2‐ and ZnO‐catalyzed phenol photodegradation rates

“…So are the reports on the susceptibility of substituted phenols to photodegradation, but the results are contra-dictory. The presence of chlorine in the phenyl ring slows down the degradation, and the ease of degradation on TiO 2 , TiO 2 film, and Ag-TiO 2 is p-Cl > o,p-Cl 2 > o,o ,p-Cl 3 > Cl 5 [12,13], H > p-Cl > o,p-Cl 2 ≈ o,m,p-Cl 3 [14], and H > o,p-Cl 2 > o,m,m -Cl 3 > Cl 5 [15], respectively. However, some reports present the order as o,o ,p-Cl 3 > o,p-Cl 2 > o-Cl [16] and p-Cl ≥ o-Cl > m-Cl ≈ H ≈ o,p-Cl 2 [17][18][19][20][21].…”