Modelling and optimization of photocatalytic mineralization of acetaminophen using ZnFe2O4-TiO2nanocomposite prepared via microwave assisted combustion method

Present work focuses on microwave assisted synthesis of ZnFe2O4-TiO2 nanocomposite and its application for photocatalytic mineralization of acetaminophen (one of the most widely used analgesic drugs) in water under visible light illumination. The synthesized ZnFe2O4-TiO2was characterized using x-ray diffractometry and scanning electron microscopy.The effects initial concentration of acetaminophen, ZnFe2O4-TiO2dosage, and irradiation time on photocatalytic mineralization of acetaminophen were investigated using the central composite design. Photocatalytic mineralization of acetaminophen using ZnFe2O4-TiO2 was described by a model quadratic equation with R^2of 0.993 and R^2 adjof 0.984. Under the optimized conditions (initial acetaminophen concentration of 11.2 mg/L, ZnFe2O4-TiO2dosage of 1.0 g/L and irradiation time of 28.7 min), 95.9 % mineralization of acetaminophen was achieved. Experiments were conducted in order to validate the model. Under the predicted optimized conditions, the experimental percentage photocatalytic mineralization of acetaminophen was found to be 95.9 % which is very close to the predicted value of 96.3%.