Laboratory of Environmental Engineering, Faculty of Engineering, Badji Mokhtar University, P.O. Box 12, 23000 Annaba, Algeria.
Water Sci Technol. 2012;66(5):953-7. doi: 10.2166/wst.2012.262.
This work was conducted to develop a suitable kinetic model for the removal of zinc (Zn) using the duckweed Lemna gibba L. as a phytoremediation agent at laboratory scale. The 7-day treatments of 6.0-18.0 mg Zn/L were performed under controlled conditions: 12 h photoperiod, temperature of 21±1 °C, pH of 6.0±0.1 and a quarter Coïc and Lesaint solution as a culture medium. The results revealed a Zn removal efficiency of 60-70% and an accumulation capacity of plants ranging from 4.23 to 25.88 mg/g DM. Two simplified kinetic models namely pseudo-first-order and pseudo-second-order were used to study the mechanism that controls the biological process. The kinetic study proved that the removal rate of Zn by L. gibba was proportional to the Zn concentration present in water. Therefore, the pseudo-first-order model was considered to be more suitable to describe the disappearance of Zn from water in the presence of fronds of L. gibba L. These results may serve as a basis in mathematical modelling for large-scale application.
本研究旨在开发一种合适的动力学模型，以利用浮萍（Lemna gibba L.）作为植物修复剂在实验室规模下去除锌（Zn）。在受控条件下进行了 7 天的 6.0-18.0 mg Zn/L 处理：12 h 光周期、21±1°C 的温度、pH 值为 6.0±0.1 以及四分之一 Coïc 和 Lesaint 溶液作为培养基。结果表明，Zn 的去除效率为 60-70%，植物的积累能力范围为 4.23 至 25.88 mg/g DM。使用两种简化的动力学模型，即拟一级和拟二级动力学模型，研究控制生物过程的机制。动力学研究证明，L. gibba 去除 Zn 的速率与水中存在的 Zn 浓度成正比。因此，认为拟一级模型更适合描述浮萍存在时水中 Zn 的消失。这些结果可以为大规模应用的数学建模提供基础。
