正长石去除镉离子的试验研究

Experimental Studies of the Interaction of Aqueous Cadmium Ion With Orthoclase

将正长石与含镉溶液混合,分别在不同时间和不同pH值条件下反应,生成了含镉长石。水溶液中镉浓度随着反应时间的延长而降低,120h后去除率达到96%。在pH值为6的近中性条件下,长石对Cd2+离子的去除率达到78.40%,且基本达到了平衡。XRD分析表明反应后的长石生成了含镉的硅酸盐相。XPS分析表明Cd 3d5/2的结合能为406.12eV,说明Cd2+与长石矿物形成了较强的离子键,表明有离子交换反应的发生。长石去除水溶液中的Cd2+既存在有吸附作用,也存在有离子交换作用,表明长石矿物具有一定的修复水体中镉离子污染的功能和效果。

The interactions between cadmium-bearing solution and orthoclase have been studied in the conditions of different mixed periods and pH value, Cd-feldspar was synthesized. The concentrations ofCd^2＋ were reduced with the reaction time extending, the remove rate of Cd^2＋ was up to 96% after 120 hours. The Cd〉 removal effect is almost up to equilibrium, about 78.40%, in the weak acid condition about pH 6. The phase composition of the reaction results was determined by XRD, showing the silicate phase cadmium-bearing occurred. The analysis of XPS were used to ascertained that the Cd 3d5/2 binding energy is 406.12eV, suggesting that Cd〉 entered the structure of orthoclase, ion exchange reaction happened and ion bond formed. Both reactions of adsorption and ion exchange were deduced for the removal of cadmium pollution. It is concluded that wide distributed and amount of feldspar has a function of treating the Cd〉 pollution in the water.