Recovery of Valuable Metals from Wastewater using Electrochemical

Abstract Today, wastewater is already considered a secondary resource due to its abundant nutrients, chemical energy content and other valuable constituents. However, recovery of valuable resources such as valuable metals from wastewater interesting to investigate. This study aims to recover valuable metalfrom wastewater using electrocoagulation (EC). This study used a cylindrically-shaped EC reactor with a total volume of 1500 mL. EC reactors are equipped with cathodes and anodes, which are spiral and cylindrical respectively. The result shows that the initial pH is low at 0.39, then decreases to 0.16 within 1 minute. After that, the pH gradually increases until it reaches its peak at 3.48 after 60 minutes. After 45 minutes, the pH increased significantly, suggesting that the electrocoagulation process could lead to an increase in pH in the wastewater. After 15 minutes, the temperature began to rise gradually, reaching 39.3°C after 60 minutes. This increase in temperature may be due to the ongoing electrocoagulation reaction and the heating effect of electrical voltage. Cr, a valuable metal, has a concentration of 2.09 mg/L, which dramatically decreases to 1.12 mg/L after 1 minute. Cr concentrations continued to decrease until they reached a low of 0.13 mg/L after 30 minutes. This indicates a significant recovery of Cr from wastewater.