Comparative study of saline industrial wastewater treatment by electron beam radiation and ozonation oxidation

This study investigates the treatment performance of saline wastewater using electron beam radiation (EB), comparing it with ozonation. The results indicate that chloride ions (Cl - ) inhibited the mineralization of all the organic pollutants, and the inhibition presented slightly enhancement with the increase of Cl - concentration. Within pH ranging from 3 to 9, Cl - had a minimal impact on the removal of organic pollutants. At pH 3.0 and pH 9.0, Cl - promoted the phenol mineralization when Cl - concentration was 1 and 5 g/L, while decreased the mineralization when Cl - was 10 g/L. Sulfate ions (SO 4 2- ) had no significant effect on removal and mineralization. Similarly, nitrate ions (NO 3 – ) had minor effect on the removal. At 1, 2 and 5 kGy, NO 3 – even enhanced the mineralization. In comparison, Cl - , SO 4 2- , and NO 3 – also had minor effect on the removal of organic pollutants by ozonation, but predominantly inhibited mineralization, except for benzoic acid, where Cl - promoted it. Mechanistic analysis suggests that inorganic ions influenced the types and utilization efficiencies of reactive species during EB, ultimately affecting pollutant degradation. While the effect of inorganic anions on ozonation was not only reflected in the reactive species, but also in the changes in solution ionic strength that further decrease the mineralization. Overall, EB radiation demonstrated superior COD removal and cost-effectiveness compared to ozonation, presenting a viable alternative for saline wastewater treatment.