MULTITRACER STUDY ON THE EFFECT OF HUMATE FORMATION ON THE ADSORPTIONBEHAVIOR OF METAL-IONS ON KAOLINITE AND SILICA-GEL

The multitracer technique was applied to elucidate of influence of hum ate formation on adsorption behavior of ultratrace elements. Dissolved fractions of Co, As, Rb, Sr, Y, Zr, Ba, Ce, Eu, Gd, Tb, Yb, Lu, Hf,Re and Pt in contact with kaolinite or silica gel were determined simult aneously either in the presence or absence of humic acid, which was pa rtly adsorbed on the solid. Percentage of dissolved fraction of rare e arth elements was identical to that of humic acid, indicating high sta bility of the are earth-humate complex. Hydrolysis was the most import ant factor controlling the behavior of Zr and Hf. Both hydrolysis and humate complexation influenced the adsorption of Co, Sr, Ba and Pt, wh ereas neither affected the distribution of As, Rb and Re.