摘要
In this paper, the adsorption-desorption variations of trivalent La, Ce, Y and mixed rare earths are discussed. The curves of pH-rare earth element adsorption were very well fitted to the equation: InD =a+b pH. The selectivity of RE (rare earth element) ions by the samples decreased in the following order: Ce> RE> La> Y, but the sequences were: La> Ce> Y on kaolinite and Y> La on amorphous iron oxide. Since the trivalent RE ions existed in the form of RE(OH)2+ in the solutions from pH < 5.45 to 7.0, the ratio of H+ displaced to RE3+ adsorbed in micromole was proposed to be about 2. The specific adsorption mechanism for RE was proposed to be that the RE ions complexed with oxide surface and the ion-surface complex of Ce3+ promoted oxidization on Mn hydroxide.
In this paper,the adsorption-desorption variations of trivalent La,Ce,Y and mixed rare earths are discussed.The curves of pH-rare earth element adsorption were very well fitted to the equation:1nD=a+b pH.The selectivity of RE(rare earth element) ions by the samples decreased in the following order:Ce>RE>La>Y,but the sequences were:La>Ce>Y on kaolinite and Y>La on amorphous iron oxide.Since the trivalent RE ions existed in the form of RE(OH)^2+ in the solutions from pH<5.45 to 7.0,the ratio of H^+ displaced to RE^3+ adsorbed in micromole was proposed to be about 2.The specific adsorption mechanism for RE was proposed to be that the RE ions complexed with oxide surface and the ion-surface complex of Ce^3+ promoted oxidization on Mn hydroxide.
