天然褐铁矿处理含Hg(Ⅱ)废水的实验研究

Disposal of Hg(Ⅱ)-bearing wastewater by natural limonite

利用水合金属氧化物和氢氧化物矿物表面重金属离子发生吸附作用的原理 ,进行了天然褐铁矿处理含Hg(Ⅱ )废水的实验。结果表明 :试样用量、粒径、废水浓度、pH值、离子强度、反应时间、振荡器转速等因素对Hg(Ⅱ )的吸附率有一定的影响 ,其中 pH值的影响最大 ;Hg(Ⅱ )在天然褐铁矿上的吸附等温曲线不同于Langmuir和Fre undlich等温线 ,而为台阶型 ,符合分级离子

The main affecting factors and adsorption isotherms in the application of natural iron_bearing oxides and hydroxides to the treatment of Hg(Ⅱ) wastewater were studied with the theory of adsorption of heavy metal ions on the surface of water_metal oxides and hydroxides. The results show that such factors as pH, ionic strength, quantity, Hg(Ⅱ) concentration, grain size, temperature, rotation speed and time exert some influence on adsorption rate, with pH playing the strongest role. In addition, the research indicates for the first time that the adsorption of Hg(Ⅱ) on natural iron_bearing oxides and hydroxides shows plateau isotherms instead of Langmuir and Freundlich isotherms, in accord with the isotherm of stepwise ion/coordination particle exchange.