Abstract
Degradation of trypan blue (TB) by persulfate/CuNPs system was investigated as a function of TB concentration, persulfate concentration, CuNPs concentration, pH, and reaction temperature in aqueous solution. The rate of the decolorization and destruction of aromatic ring were studied spectrophotometrically. The dye mineralization was performed with potassium dichromate for the determination of chemical oxygen demand (COD) in solution. The blue color reaction mixture became red-chocolate, purple, light blue to dark blue as a function of time. The CuNPs acted as an activator of K2(2)S(2)O(8) and generates various reactive oxygen and/or sulphur species. Decolorization of dye starts due to the cleavage of azo bond by the generated radical species. The role of sulfate radicals (SO4 center dot-), and hydroxyl radicals (HO center dot-) were established by using different radical scavengers. Degradation and mineralization of dye follows first-order kinetics. These results can support the design of remediation processes and also assist in predict their fate in environment (c) 2022 The Author(s). Published by Elsevier B.V. on behalf of King Saud University.