Remediation of Copper from Copper Mine Wastes and Contaminated Soils Using (S,S)-Ethylenediaminedisuccinic Acid and Acidophilic Bacteria

Abstract

The biodegradable chelating agent (S,S)-Ehylenediaminedisuccinic acid (EDDS), autochthonous acidophilic bacteria, and a combination of the two means were investigated for the removal of pseudo-total and ethylenediaminetetraacetic acid (EDTA)-available content of Cu from surface layers of three soil categories in the Bor copper mining area. Their efficiencies were compared at mine overburden, flotation tailings, and agricultural land sites in order to determine the potential role of these approaches in the soil remediation process. The most effective removal of Cu was achieved on flotation tailings, where combined treatment showed significant reduction of pseudo-total and EDTA-available concentrations of Cu (40.5 ± 27.3% and 99.6 ± 0.2%, respectively). Acidophilic bacteria treatment showed high efficiency on flotation tailings, removing 94.1 ± 1.2% of EDTA-available Cu. EDDS treatment showed discernible results in the removal of EDTA-available Cu from agricultural land soil (44.4 ± 13.9%). In the case of overburden soil material, selected agents did not have statistically significant results in the removal of pseudo-total or EDTA-available fraction of Cu. Chosen remediation approaches showed diverse efficiency for soil categories on investigated sites. Combined approach showed synergistic results in the case of EDTA-available Cu removal from flotation tailings soils, suggesting that this combination deserves further attention as a potentially promising environmentally friendly remediation option.