Cation-Exchange Properties of Zirconium (IV)–Tungsten (VI) Precipitates

Abstract

IN an investigation of adsorptive properties of inorganic materials, precipitates of tungstate brought down by addition of zirconium (IV) solutions were found to have cation-exchange properties. The adsorbent may be prepared by mixing a solution of zirconium oxychloride with a large excess of sodium tungstate solution (adjusted to pH c. 1.2 with hydrochloric acid). The precipitate (mole ratio tungsten/zirconium of about 3/1) is dried at 25° without washing, ground and screened. The conditions of preparation are not critical, so long as the acidity is not too high. Drying the precipitates for 24 hr. at temperatures above 80° C. sharply decreases both uptake of cations and the values of distribution coefficients D (amount adsorbed per kgm. adsorber/amount per litre of solution); at 150° C. the exchange properties of the solid are essentially destroyed.