Use of Energy Crop (Ricinus communis L.) for Phytoextraction of Heavy Metals Assisted with Citric Acid |
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Authors: | Hui Zhang Xueping Chen Xia Liang Kokyo Oh Xiaoyan Liu |
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Institution: | 1. School of Environmental and Chemical Engineering, Shanghai University, Shanghai, PR China;2. Center for Environmental Science in Saitama, Kisai, Saitama, Japan |
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Abstract: | Ricinus communis L. is a bioenergetic crop with high-biomass production and tolerance to cadmium (Cd) and lead (Pb), thus, the plant is a candidate crop for phytoremediation. Pot experiments were performed to study the effects of citric acid in enhancing phytoextraction of Cd/Pb by Ricinus communis L. Citric acid increased Cd and Pb contents in plant shoots in all treatments by about 78% and 18–45%, respectively, at the dosage of 10 mM kg?1 soil without affecting aboveground biomass production. Addition of citric acid reduced CEC, weakened soil adsorption of heavy metals and activated Cd and Pb in soil solutions. The acid-exchangeable fraction (BCR-1) of Pb remained lower than 7% and significantly increased with citric acid amendment. Respective increases in soil evaluation index induces by 14% and 19% under the Cd1Pb50 and Cd1Pb250 treatments upon addition of citric acid resulted in soil quality improvement. Ricinus communis L. has great potential in citric acid-assisted phytoextraction for Cd and Pb remediation. |
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Keywords: | phytoextraction Ricinus communis L citric acid cadmium lead |
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