Arsenic Removal from Contaminated Soil by Phytoremediation Combined with Chemical Immobilization

We have designed a new phytoremediation technique called phytosuction separation (PS-S). To date, it has indicated that the PS-S can remove antimony 69-533 times higher than that removed by phytoextraction (PE). However, it should be deeply investigated that PS-S can effectively remove the metalloid other than antimony. Arsenic-contaminated soil was used in this study. Ferryhydrite synthesized in the laboratory was used as an immobilization material. Four treatments for PS-S were prepared changing the amount of contaminated soil put in the pot: 1.6, 1.0, 0.5, 0.2 cm soil depth, respectively. The removal ratios of PS-S system were higher than that of PE despite the soil depth of PS-S system. The removal ratios of PS-S system increased with the decrease in the soil depth, indicating that the PS-S system could remove arsenic from less than 0.5 cm soil layer. This study indicates that the PS-S system can remove arsenic from the contaminated soil compared with PE, and it can be more effective with more shallow soil layer.