College of Chemistry and Chemical Engineering, Shaoxing University, Shaoxing, Zhejiang 312000, China E-mail:
Shaoxing Yigao Testing Technology Co., Ltd, Shaoxing, Zhejiang 312000, China.
Water Sci Technol. 2021 Nov;84(9):2446-2456. doi: 10.2166/wst.2021.434.
In this study, two-dimensional (2D) MXene material (TiCT) was employed to investigate its potentials toward the Cr(VI) removal in aqueous system by batch experiments. Characterization techniques such as SEM-EDS, HRTEM, XRD, FI-TR and XPS were used to analyze the structure and interaction of TiCT before and after Cr(VI) adsorption. The results indicated that the layered structure of TiCT had unique surface functional properties and abundant active sites, such as -OH, Ti-O, C = O, which exhibited high adsorption capacity for Cr(VI) removal. The Cr(VI) adsorption capacity by TiCT decreased with the increase of pH, and its maximum value can reach 169.8 mg/g at pH = 2.0. The adsorption kinetic was well-explained by a pseudo-second-order kinetic, indicating that chemical interaction played a dominant role in the adsorption of Cr(VI) on TiCT. Meanwhile, the isotherm data was calculated to conform to the Freundlich isotherm model. Thermodynamic analysis indicated that the adsorption process of Cr(VI) on TiCT was a spontaneous endothermic process. These experimental results revealed that TiCT had tremendous potential in heavy metals adsorption from aqueous solutions.
在这项研究中，采用二维（2D）MXene 材料（TiCT）通过批处理实验来研究其在水溶液中去除 Cr(VI) 的潜力。采用 SEM-EDS、HRTEM、XRD、FI-TR 和 XPS 等表征技术来分析 TiCT 在吸附 Cr(VI)前后的结构和相互作用。结果表明，TiCT 的层状结构具有独特的表面官能团性质和丰富的活性位点，如 -OH、Ti-O、C = O，这使其对 Cr(VI)的去除具有很高的吸附能力。TiCT 对 Cr(VI)的吸附容量随 pH 值的增加而降低，在 pH = 2.0 时最大值可达 169.8 mg/g。吸附动力学很好地解释了准二级动力学，表明化学相互作用在 Cr(VI)在 TiCT 上的吸附中起主导作用。同时，计算了等温线数据以符合 Freundlich 等温线模型。热力学分析表明，Cr(VI)在 TiCT 上的吸附过程是一个自发的吸热过程。这些实验结果表明，TiCT 在从水溶液中吸附重金属方面具有巨大的潜力。
