Sonocatalytic degradation of caffeine using CeO₂ catalyst: parametric and reusability studies

Abstract

Abstract This work examined sonocatalytic degradation of caffeine in the presence of CeO 2 prepared by hydrothermal method. Several characterization techniques were used to study the CeO 2 including TEM, XRD and BET method. Effects of various parameters such as pH, initial concentration of caffeine and dosage of CeO 2 were investigated. This study also examined the reusability of CeO 2 . Results showed that the CeO 2 had mixed shapes of crystallites consisting of rods and cubes with the specific surface area (Sbet) and pore volume of 126.63 m 2 /g and 0.4898 cm 3 /g, respectively. About 95.5% of caffeine degradation was achieved under the best parameter conditions i.e. at pH of 7.5, 5.0 mg/L of initial concentration of caffeine and 1.0 g/L of CeO 2 dosage within 150 min. It was also revealed that the operating parameters played major roles in caffeine degradation efficiency. In addition, the CeO 2 were quite stable since the efficiency of caffeine degradation achieved in the third cycle was 81.4%.