RECOVERY OF CHROMIUM FROM ELECTROCHEMICAL MACHINING WASTE BY USING ACID LEACHING

Abstract

The waste from ECM is hazardous solid wastes due to the presence of specific heavy metals such as chromium, iron, nickel, lead and molybdenum. At the same time, some of these metals are valuable and comes in high percentage in the waste such chromium, iron, and nickel. Hence, recovery of these metals has the advantages of financial and economic returns and save the environment from land disposal of heavy metal from the electrochemical machining waste, so recovery of chromium from this waste was investigated. Chromium was recovered by using hydrometallurgical method via acid leaching by using sulfuric acid (H2SO4).The experiments were designed by Taguchi method to determine the optimum conditions for chromium leaching. The optimum leaching conditions were (6 M) sulfuric acid concentration, (60 min) leaching time, and the temperature was (25 Co).