Frontiers of Environmental Science & Engineering
Reuse of heavy metal-accumulating
State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
Phytoremediation technology is regarded as a simple and efficient way to remove heavy metals from contaminated soil. A reasonable disposal of metal hyperaccumulators is always a major issue in waste reuse and resource-saving. The heavy metal-accumulating (L.) was investigated where heavy metals were desorbed by a facile acid-treatment. The result indicated that more than 90% of heavy metals (Zn, Pb and Cu) was extracted from with 0.2 mmol·L HCl. The plant residue was used to adsorb heavy metals ions. The adsorption fitted the Langmuir isotherm model with the saturation adsorption capacity of 9.5 mg·g Zn , 36.2 mg·g Pb and 12.9 mg·g Cu , and the surface complexation and the backfilling of heavy metal-imprinting cavities existed simultaneously during the adsorption. The treatment of wastewaters indicated that the plant residue exhibited a high removal rate of 97% for Cu. Also, the material could be recycled. The method offers a new disposal approach for heavy metal hyperaccumulator.