Systematic LCA-AHP Approach to Compare Hydrometallurgical Routes for Copper Recovery from Printed Circuit Boards: Environmental Analysis

Abstract

To ensure that metal recovery processes in electronic waste are truly sustainable from an industrial perspective, studies on the performance of such methodologies are necessary to verify the economic, environmental, social, and technological viabilities. The importance of conducting multicriteria and comparative investigations into the actual performances of methods used in the recovery of these materials is emphasized, considering trade-offs such as high efficiency in metal extraction balanced against intense consumption of energy and chemical reagents. The analytical hierarchy process, multicriteria decision support tool, and the life cycle assessment tool are proposed to be used in combination in this work to assess and contrast the environmental effects of two hydrometallurgical paths for the recuperation of copper in electronic circuit boards (PCBs). The results indicate that the sulfuric acid method had a copper solubilization efficiency of 90.05%, whereas the route employing the combination of ammonium sulfate and ammonia had an estimated copper solubilization efficacy of 49%. It was feasible to calculate the life cycle effects of the hydrometallurgical procedures connected to the copper recovery activities on the PCBs with regard to the LCA. Compared to the acidic leaching pathway, alkaline leaching was responsible for about 71% of the environmental damage discovered in the study, according to the AHP tool.