氢氧化铁对五价锑的吸附作用研究

Study of Absorption of Sb(V) onto Fe(OH)_3

环境中的锑近年来受到越来越多的关注,锑的化合物被美国和欧盟列为优先控制的污染物。氢氧化铁是土壤和沉积物的重要组成部分,对环境中锑的迁移转化产生重要影响。作者开展了不同pH值和初始Sb(V)浓度下氢氧化铁吸附Sb(V)的实验研究。结果表明低pH值条件下(pH≤7)Sb(V)以内层络合物的形式强烈吸附到氢氧化铁表面,而高pH值条件下由于氢氧化铁表面可交换OH的减少和KSb(OH)60离子团的形成,导致Sb(V)吸附量的减少。因此,利用铁(氢)氧化物处理含锑废水时将pH值控制在6-7之间较为合理。

Antimony is an element of growing concern in recent years and its compounds are classified as priority pollutants by the USA and European Union. Iron hydroxides are important composition of soils and sediments and play a crucial role in antimony mobility and transformation. The adsorption of Sb （V） onto Fe （OH）3 was conduc- ted in varying solution pH values and Sb （V） concentrations. The results suggest that Sb （V） adsorb strongly onto and form inner-sphere surface complex at the Fe（OH）3 surface bdow pH 7. At pH values above pH 7, Sb（V） shows decreasing adsorption capacity onto Fe （OH） 3 surface owing to decrease of exchangeable hydroxyl group and formation of KSb（ OH）6 ion pair. It is advised that pH values should be pH 6 -7 when treating Sb-bearing wastewater with iron hydroxides.