Optimization of photocatalytic degradation of Cefradine using a "green" goethite/H2O2 system

An environmental friendly photocatalyst, goethite in the presence of H2O2, was used to remove Cefradine from aqueous solution. Four factors were examined using Box-Behnken Design and results were analyzed by response surface method. H2O2 concentration had the largest effect on Cefradine removal and the optimal reaction conditions were: H2O2 concentration, 4 mmol/L; solution pH, 5; goethite dosage, 1.2 g/L and illumination time, 9 h. Experimental data on Cefradine removal under optimal conditions closely coincided with model predictions, validating the model. Hydroxyl radicals ((OH)-O-center dot) and superoxide anion were involved in the Cefradine photodegradation process and that (OH)-O-center dot makes the larger contribution. (C) 2019 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.