Ningbo Institute of Technology, Zhejiang University, Ningbo 315100, China.
J Colloid Interface Sci. 2012 Jan 1;365(1):204-12. doi: 10.1016/j.jcis.2011.09.002. Epub 2011 Sep 14.
In this study, mercapto-functionalized nano-Fe(3)O(4) magnetic polymers (SH-Fe(3)O(4)-NMPs) have been prepared and characterized by transmission electron microscopy (TEM), X-ray diffractometer (XRD), vibrating sample magnetometer (VSM), thermogravimetry and differential thermogravimetry analyses (TG-DTA), as well as Fourier-transformed infrared spectroscopy (FTIR). The adsorptive characteristics of the SH-Fe(3)O(4)-NMPs intended for removal of mercury (II) were deeply studied. The results showed that the adsorption efficiency increased with pH increasing and reached a plateau at pH above 3.0. The adsorption data obtained at the optimized condition, i.e., 308 K and pH of 3.0, were well fitted with the Freundlich isotherm. The adsorption of Hg(II) reached equilibrium within 60 min. Thermodynamic parameters such as ΔH(θ), ΔS(θ) and ΔG(θ) suggested that the adsorption processes of Hg(II) onto the SH-Fe(3)O(4)-NMPs were endothermic and entropy favored in nature, with ΔH(θ) at 30.31 kJ mol(-1), ΔS(θ) at 111.41 J mol(-1) K(-1). The effects of mercury salts, i.e., Hg(NO(3))(2), HgSO(4), and different acids, were also deeply investigated and showed that the adsorption capacity of Hg(II) onto the SH-Fe(3)O(4)-NMPs decreased when Cl(-) existed.
在这项研究中，制备了巯基功能化的纳米 Fe(3)O(4)磁性聚合物（SH-Fe(3)O(4)-NMPs），并用透射电子显微镜（TEM）、X 射线衍射仪（XRD）、振动样品磁强计（VSM）、热重和差热分析（TG-DTA）以及傅里叶变换红外光谱（FTIR）进行了表征。深入研究了 SH-Fe(3)O(4)-NMPs 对汞（II）的吸附特性。结果表明，吸附效率随 pH 值的升高而增加，在 pH 值高于 3.0 时达到一个平台。在优化条件下（即 308 K 和 pH 为 3.0）获得的吸附数据与 Freundlich 等温线拟合良好。Hg(II)的吸附在 60 min 内达到平衡。热力学参数如ΔH(θ)、ΔS(θ)和ΔG(θ)表明，Hg(II)在 SH-Fe(3)O(4)-NMPs 上的吸附过程是吸热的，本质上有利于熵的增加，其中ΔH(θ)为 30.31 kJ mol(-1)，ΔS(θ)为 111.41 J mol(-1) K(-1)。还深入研究了汞盐（如 Hg(NO(3))(2)、HgSO(4)）和不同酸的影响，结果表明当存在 Cl(-)时，Hg(II)在 SH-Fe(3)O(4)-NMPs 上的吸附容量降低。
