Lead And Antimony Removal From Contaminated Soil By Phytoremediation Combined With An Immobilization Material
Published 2016 · Chemistry
Phytoextraction (PE) requires long periods for the removal of heavy metals from contaminated soil, even when using a hyperaccumulator. Thus, we designed a new phytoremediation technique called phytosuction separation (PS-S), in which a material that immobilized heavy metals was placed onto contaminated soil and plants were grown on the upper layer of this material. Heavy metals in the soil were transported toward the upper layer by the water suction effect of the roots and immobilized by the material and then removed from the contaminated soil. A pot experiment was conducted to evaluate the ability of PS-S to remove lead (Pb) and antimony (Sb) from the soil. We found that evapotranspiration and shoot biomass were significantly higher in plants grown using PS-S than those grown using PE. The pot experiment demonstrated that PS-S was effective in removing Pb and Sb, and the concentrations of Pb and Sb removed by PS-S were 8–25 and 69–533 times higher than that removed by PE, respectively. Sb could be effectively removed by PS-S from contaminated soil where the concentration of Sb removed corresponded to 166–380% of water-soluble Sb in contaminated soil. This study clearly demonstrated that PS-S was effective in removing Pb and Sb from the contaminated soil and would be particularly useful for removing elements with high mobility.