Cui Limei, Guo Xiaoyao, Wei Qin, Wang Yaoguang, Gao Liang, Yan Liangguo, Yan Tao, Du Bin
School of Resources and Environment, University of Jinan, Jinan 250022, China.
Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China.
J Colloid Interface Sci. 2015 Feb 1;439:112-20. doi: 10.1016/j.jcis.2014.10.019. Epub 2014 Nov 1.
Xanthate functionalized magnetic graphene oxide (Fe3O4-xGO) was successfully synthesized through linking xanthate groups to a kind of graphenes magnetic material (Fe3O4-GS). Fe3O4-xGO was found to be an ideal adsorbent for Hg(II) and methylene blue removal with a higher adsorption capacity. The synthesized adsorbent was characterized by SEM, TEM, FTIR, XRD, and BET respectively. Fe3O4-xGO can be simply recovered from water with magnetic separation at low magnetic field within only 1min. The adsorption capacity was found to be 118.55mg g(-1) for Hg(2+) (contact time for 180min, pH at 7 and temperature at 25°C) and 526.32mg g(-1) for methylene blue (contact time for 120min, pH at 5.5 and temperature at 25°C), respectively. Kinetic data showed good correlation with pseudo-second-order equation and the Langmuir model was found to fit for the isotherm data, which showed the contaminant sorption was accomplished mainly via chelation or ion exchange. The results of thermodynamic studies (ΔG<0, ΔH>0, ΔS>0) illustrate that the adsorption process was endothermic and spontaneous in nature. The experimental results suggest that Fe3O4-xGO has the potential applications in the environmental management.
通过将黄原酸酯基团连接到一种石墨烯磁性材料（Fe3O4-GS）上，成功合成了黄原酸酯功能化的磁性氧化石墨烯（Fe3O4-xGO）。发现Fe3O4-xGO是去除Hg(II)和亚甲基蓝的理想吸附剂，具有较高的吸附容量。分别用扫描电子显微镜（SEM）、透射电子显微镜（TEM）、傅里叶变换红外光谱（FTIR）、X射线衍射（XRD）和比表面积分析仪（BET）对合成的吸附剂进行了表征。在低磁场下仅需1分钟，Fe3O4-xGO就能通过磁分离简单地从水中回收。发现对Hg(2+)的吸附容量为118.55mg g(-1)（接触时间180分钟，pH值为7，温度为25°C），对亚甲基蓝的吸附容量为526.32mg g(-1)（接触时间120分钟，pH值为5.5，温度为25°C）。动力学数据与准二级方程显示出良好的相关性，并且发现Langmuir模型适用于等温线数据，这表明污染物的吸附主要通过螯合或离子交换完成。热力学研究结果（ΔG<0，ΔH>0，ΔS>0）表明吸附过程是吸热的且本质上是自发的。实验结果表明Fe3O4-xGO在环境治理方面具有潜在应用。
