Degradation of Calmagite by H2O2/UV/US, H2O2/US, H2O2, and US process

1-(1-Hydroxy-4-methyl-2-phenylazo)-2-naphthol-4-sulfonic acid is known as Calmagite. In this study, the degradation of Calmagite in H2O2/UV/US, H2O2/US, H2O2, and US processes were investigated separately and each was compared among themselves. The concentration of H2O2, initial dye concentration, pH, UV light, and also ultrasonic sound significantly influenced the degradation of Calmagite and these parameters were optimized. For the azo dye tested, more than 98% of degradation in H2O2/UV/US, H2O2/US, and H2O2 processes was reached in 20, 40, and 60 min, respectively in Britton Robinson buffer media at pH = 11.0. The proposed degradation pathways of Calmagite were established from the (OH)-O-center dot mediated degradation of this azo dye. The first-order rate kinetics best fit the degradation of Calmagite. (C) 2021 THE AUTHORS. Published by Elsevier BV on behalf of Faculty of Engineering, Alexandria University.