Selective Recovery of Copper from Printed Circuit Board Leachate Using Cementation on Iron Scrap

Abstract

The rapid growth of electronic waste has increased the need for efficient recovery technologies for valuable metals present in discarded printed circuit boards (PCBs). This study investigates the selective recovery of copper from PCB leachate through cementation using iron scrap as an economical and environmentally sustainable hydrometallurgical technique. The process utilizes the difference in electrochemical potential between iron and copper to facilitate selective metal deposition from acidic leach solutions. Experimental investigations were conducted to evaluate the effects of pH, temperature, reaction time, agitation speed, iron scrap dosage, and initial copper concentration on cementation efficiency and copper recovery performance. Results demonstrated that iron scrap effectively reduced dissolved copper ions and achieved high recovery efficiency with minimal co-precipitation of impurity metals. The cementation process exhibited rapid reaction kinetics and stable operational performance under optimized conditions, leading to the formation of high-purity metallic copper deposits suitable for recycling and industrial reuse. Surface morphology and compositional analyses confirmed efficient copper deposition on iron surfaces and progressive dissolution of the sacrificial metal. Kinetic evaluation indicated that mass transfer and electrochemical reaction mechanisms significantly influence the overall cementation rate. Compared with conventional metal recovery methods, cementation using iron scrap offers advantages such as low operational cost, simple process design, reduced chemical consumption, and minimal secondary waste generation. The findings highlight the potential of cementation as a practical and sustainable approach for copper recovery from electronic waste streams, supporting resource conservation, circular economy strategies, and environmentally responsible recycling practices in the metallurgical and electronic waste management industries.