Application of advanced oxidation process for the removal of synthetic water-based printing dye and microplastics from aqueous solution

Abstract

Starting from the assumption that wastewater treatments can have a significant impact on the interactions between microplastics (MPs) and various pollutants in different matrices, a focus must be directed on examination of classic and redesigned treatments to remove synthetic dyes in the presence of MPs from wastewater. This paper investigates the potential application of Fenton-like process for the removal of water-based printing dye (Cyan) from aqueous solution containing MPs in a form of granulated polyethylene (PEg). The influence of five quantitative parameters on decolorization efficiency was investigated: initial dye concentration (20-180 mgL-1), nano zero valent iron (nZVI) dosage (0.75-60 mgL-1), PEg concentration (1-10 gL-1), hydrogen-peroxide concentration (1-11 mM) and pH value (2-10). A novel statistical approach, definitive screening design, resulted with the optimization process which yielded highest removal efficiency of 92% under following conditions: initial dye concentration of 155 mgL-1, nZVI dosage of 55 mgL-1, PEg concentration of 2.35 gL-1, H2O2 concentration of 2 mM and pH value 2.5. Available data indicate that in the future, wastewater containing MPs will dictate ways to reuse this water in terms of closing the water material cycle and reducing environmental pollution. Therefore, the industrial wastewater reuse is an important component of sustainable wastewater management practices, namely, water resource augmentation and pollutant reduction.