Chelation and AOP Approach on Mn-Metal and COD Reduction of Liquid Laboratory Waste

Abstract

Heavy metal waste and organic material used in flushing laboratory glassware can accumulate and potentially damage the environment. Thus, it needs to be processed before being disposed of to avoid any damage to the aquatic ecosystem. This research aimed to determine the pH wastewater sample and APDC concentration as chelating agents that would be the best for chelation treatment and determine the H2O2 concentration and UV exposure duration to identify the best treatment for the advanced oxidation process. This research was expected to find an alternative in wastewater treatment and provide an overview of the interaction of chelation treatment with organic pollutants as the basis for AOP-treatment management. Laboratory wastewater quality has improved through the extraction treatment of chelate from the pH 4 experiment, ammonium pyrrolidine dithiocarbamate (APDC) concentration at 7.5% with the manganese metal value decreased by 53%, an advanced oxidation process (AOP) treatment of H2O2 concentration at a 5.10-5%, and 31-hour UV exposure, resulting in chemical oxygen demand (COD) decreased by 98.98%. Waste containing both materials was reduced by combining the extraction of chelate formation and AOP, which was detected from the presence of manganese metal and the COD. This treatment can be an appropriate and easy way to degrade laboratory waste in a mini wastewater treatment process. This research succeeded in finding several novelties: first, a suitable pH value to reactivate Mn metal for chelation with APDC; second, the concentration of APDC determined to optimize the Mn metal chelate; third, the concentration of H2O2 to increase the effectiveness of organic matter reduction; fourth, the duration of UV irradiation is effective and efficient as a photocatalyst to reduce organic matter.