Iron and copper recovery/removal from industrial wastes: A review

Abstract

Surface finishing of steel sheets and strips for the removal of iron oxide scale generates a huge amount of waste sulfate/chloride pickle liquor. Similarly large quantity of bleed stream is generated in the electrolysis industries due to the build up of acidity and metal impurity. The nature of the waste generated has become complex and hazardous in nature. Their impacts on ecological bodies are noticeable due to their toxic nature which is an alarming issue to the environmentalist. Hence, their treatment before disposal is mandatory. With the increasing demand for metals in industry and the depletion of land based resources, the focus of the research community is on the development of new approaches for the recovery of metal values from waste and recycle the water back to the system or dispose of it safely. This paper is a critical review on the waste streams generated from iron and steel industries and copper electro refining industries. Various aspects on the metal value recovery from these wastes are being dealt with. The main focus is on iron recovery from waste pickle liquor and copper recovery from copper electro plating/electro refining units by solvent extraction methods. Various solvents used for metal extraction are discussed he