Sorption Behavior of Microamounts of Zinc on Titanium Oxide from Aqueous Solutions

Abstract
The adsorption of microamounts of zinc on titanium oxide, prepared and characterized in this laboratory, has been studied in detail. Zinc adsorption has been found to be dependent on the pH of the aqueous solution, amount of oxide, and zinc concentration. Maximum adsorption is from pH 10 buffer. EDTA and cyanide ions inhibit adsorption significantly. The adsorption of other elements under optimal conditions has also been measured on this oxide. Sc(III) and Cs(I) show almost negligible adsorption. Zinc adsorption follows the linear form of the Freundlich adsorption isotherm: with A = 0.48 mol/g and n = 1. Except at a very low bulk concentration (3 × 10−5 mol/dm3), the Langmuir adsorption isotherm is also linear for the entire zinc concentration investigated. The limiting adsorbed concentration is estimated to be 0.18 mol/g.