Pb^(2+)在稀土掺杂纳米氧化铁表面的吸附行为

Adsorption Behavior of Pb^(2+) on the Surface of Rare-Earth-Doped Iron Oxide

采用溶胶-凝胶法制备稀土元素(La、Ce)掺杂改性的纳米氧化铁,利用原子吸收分光光度计(AAS)测定pH值的变化及掺杂的稀土元素对吸附重金属离子Pb2+的影响。根据Pb2+在样品表面的吸附数据,运用W inSGW软件拟合计算出相应的络合平衡常数。结果表明:La、Ce的掺杂提高了纳米氧化铁的比表面积及表面吸附容量,得出的络合平衡常数均为10-1.2,而相应的表面电容有所不同。

Rare earth elements La,Ce-doped iron oxides were prepared by sol-gel method,and the effects of pH and doped elements on the adsorption of heavy metal ion Pb2＋ were measured using atomic absorption spectrophotometer（AAS）.The surface complexation constants were calculated using WinSGW software,based on experimental data.Testing results show that the dopants of La and Ce can result in the increase of surface area and surface protonation capacity of nano-iron oxides,and the complexation constants of Pb2＋ on the surfaces of iron oxides with and without doping are all 10-1.2 with some differences in electrical capacity.