Leaching of heavy metal from native plants by chemical leachants

Plant biomass harvested after heavy-metal phytoremediation must be considered as a hazardous waste that should be contained or treated appropriately before disposal or reuse. This study provides an evaluation of extractants for the removal of lead from Abutilon Theophrastus biomass. The research was carried out a leaching study to determine the lead-extraction efficiency of the different leachants (water, several aqueous ammonium salts, and ethylenediaminetetraacetic acid solution as lead extractants). The result of this study showed that, lead concentrations measured in leached biomass and in leachates were significantly different among the various leachants. Also the extraction strength of the leachants followed the order ethylenediaminetetraacetic acid > ammonium citrate > water ammonium phosphate > ammonium acetate, to , achieving lead extraction efficiencies of 96%, 67%, 4.2%, 3.9% and 0.3%, respectively, in single-stage extractions. In this study, ethylenediaminetetraacetic acid is the most frequently lead extractants.