A PROCESS FOR EXTRACTION OF NICKEL FROM LOW GRADE CHROMITE ORE

摘要

The present invention is a process for the extraction of nickel from low-grade chromite ore containing 0.6 to 0.9 % nickel, said process comprises of crushing, drying and grinding of low grade Chromite Ore to obtain +100 to -400 mesh B.S.S. with 85% -200 mesh B.S.S., subjecting the crushed ore to reduction-roasting with or without pre-mixing of oil, leaching the reduced material in an ammonia-ammonium carbonate solution using oxygen or compressed air at elevated pressure of 0.2 to 1.5 kgs/cm<2>, precipitating the dissolved nickel as basic nickel carbonate and co-precipitating cobalt and recovering ammonia as well as carbon dioxide for recycle and obtaining a magnetic fraction through a wet magnetic separation technique which is suitable for use in low phosphorous iron production.