水溶性大豆多糖体外吸附Pb2+的研究

In Vitro Binding of Lead by Soybean Soluble Polysaccharides

摘要:

以水溶性大豆多糖（SSPS）为吸附剂，改变pH、吸附时间、初始Pb2+浓度、加入人体必需金属元素（Ca2+，Mg2+，Zn2+，Cu2+）探究其体外吸附Pb2+的规律性质。结果表明：适宜吸附的pH范围为4～6；等温吸附曲线符合Langmuir单层吸附模型；动力学实验表明初始Pb2+质量浓度为25 mg/L和50 mg/L时符合准一级动力学方程，初始Pb2+质量浓度为100 mg/L时符合准二级动力学方程。大豆多糖对Pb2+的选择性优于Zn2+和Mg2+，其清除Pb2+的同时可避免有益微量元素Zn2+和Mg2+的过度损失，是一种安全的Pb2+吸附剂。

Abstract:

Soybean soluble polysaccharides（SSPS），was evaluated for possible use as a kind of heavy metals adsorbent. In vitro binding of lead as affected by pH，contact time，metal concentration，and essential metals was carried out in a batch mode. The results indicated that the suitable range of pH was 4～6，lead binding isotherm was well described by Langmuir model at pH 5.5. Kinetics at low concentrations（25、50 mg/L） and high metal concentrations（100 mg/L） obeyed pseudo-first-order model and pseudo-second-order model，respectively. SSPS showed a higher selectivity toward Pb2+ than Zn2+ and Mg2+. Thus SSPS can be used as a safe detoxifying agent for Pb2+ which preventing the loss of essential metals（Zn2+ and Mg2+） successfully.