Abstract：In-situ sorbent amendment is a promising contaminated sediment remediation technology. The immobilization of phosphorus (P) in Taihu Lake sediment-water systems using lanthanum-modified zeolite (LaMZ) as a novel amendment was investigated by conducting a series of experiments. P could be released from unamended and LaMZ-amended Taihu Lake sediments at a very low initial concentration of P in water. The amount of P released from LaMZ-amended Taihu Lake sediment was less than that from Taihu Lake sediment. The content of NaOH-P (P extracted with NaOH) or HCl-P (P extracted with HCl) in LaMZ-amended Taihu Lake sediment was higher than that in Taihu Lake sediment. The content of BD-P (P extracted with bicarbonate dithionite) in LaMZ-amended Taihu Lake sediment was less than that in Taihu Lake sediment. The equilibrium sorption of phosphate from aqueous solution at a high initial concentration of P (0.5~15mg/L) could be described by the Langmuir isotherm model. The phosphate sorption capacity for LaMZ-amended Taihu Lake sediment was much higher than that for Taihu Lake sediment. The phosphate sorption capacity for LaMZ-amended Taihu Lake sediment decreased with increasing aging time. Sequential extraction of P from phosphate-sorbed Taihu Lake sediment and LaMZ-amended Taihu Lake sediment indicated that most of sorbed phosphate onto LaMZ existed in NaOH-P and HCl-P forms, and was relatively stable and unlikely to be released under anaerobic condition. Results of this work indicate that in-situ LaMZ amendment is a promising method for controlling P release from Taihu Lake sediment.
李佳, 詹艳慧, 林建伟, 杨孟娟, 方巧, 郑雯婧. 镧改性沸石对太湖底泥-水系统中磷的固定作用[J]. 中国环境科学, 2014, 34(1): 161-169.
LI Jia, ZHAN Yan-Hui, LIN Jian-Wei, YANG Meng-Juan, FANG Qiao, ZHENG Wen-Jing. Immobilization of phosphorus in Taihu Lake sediment-water systems by lanthanum-modified zeolite. CHINA ENVIRONMENTAL SCIENCECE, 2014, 34(1): 161-169.
