Method for phytomining of nickel, cobalt and other metals from soil
AssigneesThe United States of America as represented by the Secretary of Agriculture, University of Maryland
InventorsRufus L. Chaney, Jay Scott Angle, Yin-Ming Li
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Abstract
The recovery of nickel, cobalt and other metals by phytomining is described. Plants of the Alyssum genus are grown in nickel rich soil. The uptake of nickel is enhanced by maintaining specific soil conditions, including a concentration of calcium between (but not including) 0.128 mM an 5.0 mM and an acidic pH. Ni uptake may be further enhanced by maintaining a ratio of exchangeable Ca/Mg of 0.16-0.40. Uptake may be further enhanced by addition of chelating agents and ammonium based fertilizers.
Claims11
A method of recovering nickel from soil rich in nickel, comprising:
- (a) growing a nickel hyperaccumulating plant selected from the genera Alyssum on said soil, while maintaining soil conditions such that the concentration of calcium in said soil is from about 0.128 mM to about 5 mM and said pH is maintained below about 7.0,
- (b) allowing said growth to continue until such time as the concentration of Ni in the above ground tissues of said plant is over 1000 mg per kg gross dry weight of the above ground tissues,
- (c) drying said above ground tissues, and
- (d) recovering Ni from said above ground tissues.
Dependencies are inferred from the claim text.