核壳结铁纳米线对水中Cd^(2+)的吸附性能及机理

Adsorption performance and mechanisms of Cd^(2+) ions from aqueous solution using Fe@Fe_2O_3 nanowires

利用液相还原法制备得到的核壳结构的铁纳米线(Fe@Fe_2O_3)进行了去除水中Cd^(2+)的实验研究。考察了溶液初始pH、金属离子浓度、反应时间、吸附剂投加量、反应温度等因素对于吸附反应的影响。采用了X射线衍射(XRD)、扫描电子显微镜(SEM)、X射线能量弥散分析(EDS)以及X射线光电子能谱(XPS)等分析手段对材料进行了表征并分析去除机理。结果表明,Fe@Fe_2O_3纳米线可以有效快速去除水溶液中的Cd^(2+),吸附机理涉及物理吸附和化学吸附,无氧化还原反应发生。

Removal of Cd2＋ from aqueous solution using core-shell structure zero-valent iron nanowires（ Fe@Fe_2O_3） prepared by the liquid-phase reduction method was investigated. The effects of the main parameters such as pH,initial Cd2＋ concentration,dosage,reaction time,and temperature on the sorption of Cd2＋ on Fe@Fe_2O_3 were investigated. The as-prepared and Cd-loaded Fe@Fe_2O_3 nanowires were characterized by X-ray powder diffraction（ XRD）,scanning electron microscopy（ SEM）,energy-dispersive X-ray spectroscopy（ EDS）,and X-ray photoelectron spectroscopy（ XPS） to identify the elemental composition and structure of the adsorbents and verify the Fe@Fe_2O_3 removal mechanisms. Fe@Fe_2O_3 nanowires proved to be a promising candidate for the removal of Cd2＋ from aqueous solution. The mechanisms of Cd2＋ sorption on the Fe@Fe_2O_3 nanowires involved both physical adsorption and chemical adsorption,with no reduction of Cd2＋.