Alexander Jock Asanja, Surajudeen Abdulsalam, Aliyu El-Nafaty Usman, Omeiza Aroke Umar, Zaini Muhammad Abbas Ahmad
Chemical & Petroleum Option, Department of Science Laboratory Technology, University of Jos, Plateau, Nigeria.
Department of Chemical Engineering, Abubakar Tafawa Balewa University, Bauchi, Nigeria.
Water Sci Technol. 2017 Oct;76(7-8):2232-2241. doi: 10.2166/wst.2017.391.
The present work was aimed at evaluating the multi-metals column adsorption of lead(II), cadmium(II) and manganese(II) ions onto natural bentonite. The bentonite clay adsorbent was characterized for physical and chemical properties using X-ray diffraction, X-ray fluorescence, Brunauer-Emmett-Teller surface area and cation exchange capacity. The column performance was evaluated using adsorbent bed height of 5.0 cm, with varying influent concentrations (10 mg/L and 50 mg/L) and flow rates (1.4 mL/min and 2.4 mL/min). The result shows that the breakthrough time for all metal ions ranged from 50 to 480 minutes. The maximum adsorption capacity was obtained at initial concentration of 10 mg/L and flow rate of 1.4 mL/min, with 2.22 mg/g of lead(II), 1.71 mg/g of cadmium(II) and 0.37 mg/g of manganese(II). The order of metal ions removal by natural bentonite is lead(II) > cadmium(II) > manganese(II). The sorption performance and the dynamic behaviour of the column were predicted using Adams-Bohart, Thomas, and Yoon-Nelson models. The linear regression analysis demonstrated that the Thomas and Yoon-Nelson models fitted well with the column adsorption data for all metal ions. The natural bentonite was effective for the treatment of wastewater laden with multi-metals, and the process parameters obtained from this work can be used at the industrial scale.
本研究旨在评估天然膨润土对铅（II）、镉（II）和锰（II）离子的多金属柱吸附性能。采用X射线衍射、X射线荧光、布鲁诺尔-埃米特-泰勒比表面积和阳离子交换容量等方法对膨润土吸附剂的物理和化学性质进行了表征。使用5.0 cm的吸附剂床层高度，在不同的进水浓度（10 mg/L和50 mg/L）和流速（1.4 mL/min和2.4 mL/min）下评估柱性能。结果表明，所有金属离子的穿透时间为50至480分钟。在初始浓度为10 mg/L和流速为1.4 mL/min时获得最大吸附容量，其中铅（II）为2.22 mg/g，镉（II）为1.71 mg/g，锰（II）为0.37 mg/g。天然膨润土去除金属离子的顺序为铅（II）>镉（II）>锰（II）。使用亚当斯-博哈特、托马斯和尹-尼尔森模型预测了柱的吸附性能和动态行为。线性回归分析表明，托马斯和尹-尼尔森模型与所有金属离子的柱吸附数据拟合良好。天然膨润土对含多金属废水的处理有效，本研究获得的工艺参数可用于工业规模。
