Radiotracer technique in adsorption study-IX. Adsorption of iodide ions on titanium(IV) oxide powder

Abstract

The adsorption of iodide ions on titanium(IV) oxide powder has been investigated as a function of concentration (10-7-10-2 M), temperature (303-328 K) and pH (1.9-11.9) of the adsorptive solution, employing the radiotracer technique. The rate of uptake of I- was fast initially, slowly decreased with time and finally reached a plateau within ca 6 h. The uptake of iodide ions follows first order kinetics, obeys the Freundlich isotherm and increases with the increase in concentration and decrease in temperature and pH of the adsorbate. Pretreatment of the oxide adsorbent with neutrons and γ-radiations from a 300 mCi (RaBe) neutron source has been associated with decrease in the adsorption capacity of the oxide. The adsorption process involved in the present system is thought to be chemical (ion exchange type) in nature. © 1992.