Degradation of Trimethoprim Using the UV/Free Chlorine Process: Influencing Factors and Optimal Operating Conditions

Trimethoprim (TMP) is a pharmaceutical compound, which commonly found in the water environment. The UV/chlorine process forms several reactive species, including hydroxyl radicals (HO•) and chlorine to degrade contaminants. influencing factors optimal operational conditions for degradation of TMP by were investigated. was much faster as compared UV alone or free process. A kinetic model developed simulate determine unknown rate constants. This study also predicted relative contributions each species photolysis using model. It that ClO• radical major reactant responsible TMP. Furthermore, most important finding identification best conditions. resulted lowest use energy electrical per order (EE/O), namely, (1) ultrapure water, optimum intensity light dosage 2.56 Einstein/L·s 0.064 mM, respectively, with minimum EE/O 0.136 kWh/m3; (2) matrix containing 3 mg/L NOM, 3.45 Einstein/L s 0.172 0.311 kWh/m3.