Department of Environmental Science, Laboratory of Applied Environmental Chemistry, The University of Kuopio, FI-50100 Mikkeli, Finland.
J Hazard Mater. 2009 Nov 15;171(1-3):1071-80. doi: 10.1016/j.jhazmat.2009.06.111. Epub 2009 Jun 27.
In this study, the removal of Co(II) and Ni(II) ions from contaminated water was investigated using silica gel materials functionalized with both ethylenediaminetetraacetic acid (EDTA) and diethylenetriaminepentaacetic acid (DTPA). The modified adsorbents were characterized using elemental analysis, surface area and pore size analysis, and zeta potential analysis. The adsorption and regeneration studies were conducted in batch mode. The optimum conditions for the removal of both metals at an initial concentration of 10mg/L were 2g/L of dose, pH 3, 50 rpm of agitation speed and 4h of contact time. The removal of Co(II) and Ni(II) by EDTA- and/or DTPA-modified silica gels was substantially higher than that by their unmodified form. The maximum Co(II) and Ni(II) uptakes by the EDTA-modified silica gel were 20.0 and 21.6 mg/g, comparable to their adsorption capacities by DTPA-modified silica gel (Co(II): 16.1mg/g; Ni(II): 16.7 mg/g). At the same concentration of 10mg/L, the removal of both metals by the modified adsorbents ranged from 96% to 99%. The two-site Langmuir model was representative to simulate adsorption isotherms. The kinetics of Co(II) and Ni(II) adsorption by modified silica gels followed pseudo-second-order.
在这项研究中，使用同时功能化有乙二胺四乙酸（EDTA）和二乙烯三胺五乙酸（DTPA）的硅胶材料来研究从受污染的水中去除 Co(II) 和 Ni(II) 离子。通过元素分析、表面积和孔径分析以及动电电势分析对改性吸附剂进行了表征。吸附和再生研究在批量模式下进行。在初始浓度为 10mg/L 的情况下，去除两种金属的最佳条件为 2g/L 的剂量、pH 值 3、50rpm 的搅拌速度和 4h 的接触时间。与未改性形式相比，EDTA 和/或 DTPA 改性硅胶对 Co(II) 和 Ni(II) 的去除率要高得多。EDTA 改性硅胶对 Co(II) 和 Ni(II) 的最大吸附量分别为 20.0 和 21.6mg/g，与 DTPA 改性硅胶的吸附容量相当（Co(II)：16.1mg/g；Ni(II)：16.7mg/g）。在相同的 10mg/L 浓度下，改性吸附剂对两种金属的去除率范围为 96%至 99%。双位点 Langmuir 模型是模拟吸附等温线的代表性模型。改性硅胶对 Co(II)和 Ni(II)的吸附动力学符合拟二级动力学模型。
