Adsorption of Cobalt(II) Ions on Crystalline Hydrous Titanium Dioxide Fibers at 298 to 423 K

Abstract

Abstract The distribution of cobalt(II) ions between crystalline hydrous titanium dioxide fibers and aqueous solutions has been investigated. The adsorption behavior of cobalt(II) ions is explained in terms of their ion exchange with hydrogen-ions in the fibers. The distribution coefficients of cobalt(II) ions, Kd, increased with increasing temperature at 298–373 K. Slopes of the plots of logKd vs. pH for 398–423 K were ca. +1.6, which was somewhat lower than those for 298–373 K: +2.0. X-Ray powder diffraction patterns indicate that the fibers hold a layer structure up to 373 K but change to anatase or its precursor above this temperature.