Tatsuya ISEKI

Iron and manganese hydroxide particle lead ion priority adsorption.

Kazunori SATO

Goethite particles are stable in the wide range of aquatic solution and can be synthesized by the dissolution and recrystallization of Ferrihydrite generated from Fe(NO3) 3. Mn-Goethite has been focused in this research as a promising adsorbates for lead ions in an aquatic environment. The influence of the content of manganese on the adsorption characteristic on Cu(II) , Pb(II), and Zn(II) ions was examined. The lattice constant measurement by X-ray diffraction for Mn-Goethite particles have shown the solid solubility limit of Mn ions. The MnO2H2O phase appears for the particles including the Mn content more than about 15 mol%. The observation by transmission electron microscopy revealed that MnO2EnH2O fine particles exist with the Mn-Goethite particles. The amount of adsorption of the Pb(II) ion increased with an increase of the solution pH. The amount of adsorbed Pb(II) ions increased with the Mn content. The amount of Cu(II) ion adsorption was not significantly affected by the Mn content. The results of the adsorption measurement showed that the Mn-Goethite particle and the MnO2EnH2O has an ability of preferential adsorption of Pb(II) ions. This effect is most likely to be controlled by the surface electric potential of the particles.