Method for plant mining nickel, cobalt and other metals from soil

摘要

Nickel/cobalt, as well as platinum and palladium metal family members are recovered from soil by growing Brassicaceae plants, specifically Alyssum in soil containing nickel/cobalt as well as other metals. The soil is conditioned by maintaining a low pH, low calcium concentration, and the addition of ammonium fertilizer and chelating agents thereto. Nickel accumulation on the order of 2.5 percent or better in above-ground tissues is achieved, which permits recovery of the metal by harvesting the above-ground plant materials, drying, and then combusting the same, to oxidize or vaporize organic materials and recover the metals sequestered therein at 10-20 fold higher concentrations than in the soil, in a form which can be used in conventional Ni refinery or smelting operations.