绿锈的结构特征与反应活性

Structural characteristics and reactivity of green rust

绿锈是一类含Fe(Ⅱ)和Fe(Ⅲ)的过渡态化合物,因制备成本低、还原吸附效率高、反应活性强和比表面积大等优势在国际上备受关注。绿锈具有层状双金属氢氧化物(LDH)夹层结构,能吸附重金属离子、有机阴离子以及无机离子而形成内层复合物;绿锈中亚铁形态具有较低的还原电位,其还原活性高,在碱性缺氧条件下对污染物的还原去除起关键作用,因而绿锈对水环境污染的修复起了重要作用。综述了绿锈用于废水处理及反应机理的最新研究进展,包括绿锈的制备表征、结构特点以及吸附还原机理等,同时对含结构态亚铁的绿锈应用存在的挑战、未来的发展趋势及前景进行了展望。

Green rusts （GRs） are transition state compounds containing both ferrous and ferric iron, which have attracted much attention worldwide due to low cost for preparation, high adsorption and reduction efficiency, strong reactivity and large specific surface area, but few studies have been done in China. GRs can form the inner layer complex by absorbing heavy metal ions, organic anions and inorganic ions for the layered double hydroxides （LDH） interlayer structure. Ferrous iron of green rust has a lower reduction potential and high activity. It plays a key role in pollutant removal in alkaline hypoxic environment, thus GRs are of great importance in water pollution remediation. This review summarizes the latest representative achievements in the use of green rusts for wastewater treatment and reaction mechanisms, including preparation characterization, structural characteristics, adsorption and reduction mechanisms of green rusts. The challenges and future research trends of green rusts application with structural ferrous iron are suggested.