Adsorption of copper(II) and chromium(VI) on diaspore

Abstract

The adsorption of Cu(II) and Cr(VI) on diaspore was studied with the help of X-ray diffraction analysis, BE measurement, zeta potential measurement and atomic adsorption spectrometry. The adsorption equilibrium almost reaches within 60 min. The adsorption isotherms of Cu(II) and Cr(VI) could be well described by the Langmuir equation. The adsorption capacities o Cu(II) and Cr(VI) are 1.944 and 1.292 mg/g, respectively. The adsorption percentage of Cr(II) increases with the increment solution pH, but the adsorption percentage of Cr(VI) decreases. This could be explained by zeta potential theoretical and electrostatic attraction between metal ions and diaspore surface.

Keywords

diaspore / adsorption / copper(II) / chromium(VI) / zeta potentia

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