海水中氨基酸对Cu(Ⅱ)在r-MnOOH上吸附的影响

THE EFFECT OF AMINO ACIDS ON THE ADSORPTION OF Cu(Ⅱ) ON r-MnOOH IN SEAWATER

实验测定了海水中氨基酸存在下Cu(Ⅱ)在r-MnOOH上吸附的等温线、Cu(Ⅱ)％—pH曲线和Cu(Ⅱ)％—氨基酸浓度曲线。结果表明,较低浓度氨基酸对Cu(Ⅱ)在r-MnOOH上吸附没有影响,而较高浓度氨基酸却起抑制作用,这主要是由于海水中Cu(Ⅱ)—氨基酸络合反应与r-MnOOH竞争Cu(Ⅱ)所致。此外,海水中较高浓度氨基酸只使Cu(Ⅱ)在r-MnOOH上吸附的表面分级离子交换稳定常数K_1(i=1,2,3)略有减小。

We experimentally measured the adsorption isotherms, the plots of Cu (II) %-pH and of Cu(II)%-amino acid concentration for the adsorption of Cu(II) on r-MnOOH in the presence of amino acid in seawater. The experimental results show that amino acid of lower concentrations does not affect the adsorption of Cu(II) on r-MnOOH in seawater, but higher concentrations (such as 20.0mg/l) inhibit, mainly due to the Cu(II)-amino acid complex reaction in seawater competing with r-MnOOH for Cu(II). In addition, amino acid of higher concentrations decreases the interfacial stepwise ion exchange stability constants ki (i=1, 2, 3) for the adsorption of Cu(II) on r-MnOOH in seawater.