Li Deliang, Ding Ying, Li Lingling, Chang Zhixian, Rao Zhengyong, Lu Ling
a Institute of Environmental and Analytical Sciences, College of Chemistry and Chemical Engineering, Henan University , Kaifeng 475004 , People's Republic of China.
Environ Technol. 2015 May-Jun;36(9-12):1084-90. doi: 10.1080/09593330.2014.975286. Epub 2014 Nov 3.
The removal of hexavalent chromium [Cr(VI)] from aqueous solution by using red mud activated with cetyltrimethylammonium bromide (CTAB) was studied. The optimum operation parameters, such as CTAB concentration, pH values, contact time, and initial Cr(VI) concentration, were investigated. The best concentration of CTAB for modifying red mud was found to be 0.50% (mCTAB/VHCl,0.6 mol/L). The lower pH (<2) was found to be much more favourable for the removal of Cr(VI). Red mud activated with CTAB can greatly improve the removal ratio of Cr(VI) as high as four times than that of original red mud. Adsorption equilibrium was reached within 30 min under the initial Cr(VI) concentration of 100 mg L(-1). The isotherm data were analysed using Langmuir and Freundlich models. The adsorption of Cr(VI) on activated red mud fitted well to the Langmuir isotherm model, and the maximum adsorption capacity was estimated as 22.20 mg g(-1) (Cr/red mud). The adsorption process could be well described using the pseudo-second-order model. The result shows that activated red mud is a promising agent for low-cost water treatment.
研究了用十六烷基三甲基溴化铵（CTAB）活化的赤泥从水溶液中去除六价铬[Cr(VI)]的情况。研究了最佳操作参数，如CTAB浓度、pH值、接触时间和初始Cr(VI)浓度。发现用于改性赤泥的CTAB最佳浓度为0.50%（mCTAB/VHCl，0.6 mol/L）。发现较低的pH值（<2）对Cr(VI)的去除更为有利。用CTAB活化的赤泥可大大提高Cr(VI)的去除率，比原始赤泥高出四倍。在初始Cr(VI)浓度为100 mg L(-1)的情况下，30分钟内达到吸附平衡。用Langmuir和Freundlich模型分析等温线数据。Cr(VI)在活化赤泥上的吸附很好地符合Langmuir等温线模型，最大吸附容量估计为22.20 mg g(-1)（Cr/赤泥）。吸附过程可用准二级模型很好地描述。结果表明，活化赤泥是一种有前景的低成本水处理剂。
