Sustainable treatment of ceramic manufacturing wastewater using combined advanced oxidation and coagulation/precipitation processes with green nano zero-valent iron: multi-metal corrosion monitoring

The ceramic industry generates significant amounts of wastewater, which contains many corrosive ions that pose extensive hazard to the integrity of piping systems, equipment, and machinery, resulting in increased maintenance costs, frequent equipment exchange, and downtimes. To address these issues and achieve the Sustainable Development Goals an advanced treatment process using Fenton Oxidation, coagulation/precipitation, and the addition of green "nano Zero-Valent Iron (nZVI)" was applied to "Ceramica Venezia" wastewater, one of the ceramic factories in Egypt. This study provides a unique multi-metal corrosion benchmarking analysis (Carbon Steel, Stainless Steel, and Copper) specifically examining the impact of green-nZVI advanced treatment on ceramic industrial effluent reuse in comparison with the factory's initial treatment process and untreated ceramic wastewater. The corrosion rate was evaluated using electrochemical techniques, EIS, and PDP of different metals in these two different treatment protocols. Moreover, statistical tools, including ANOVA and t-test, were applied to interpret the results. Advanced-treated water (ATW) exhibited an 86% reduction in steel corrosion and a minor improvement in stainless steel corrosion; meanwhile, worsening copper corrosion resistance. Accordingly, different treatment strategies should be studied for achieving better copper protection.