Study on adsorption characteristics of uranyl ions from aqueous solutions using zirconium hydroxide

The removal of uranyl ions from aqueous solutions using Zr(OH)4·3.35H2O (ZH) as adsorbent was investigated using a batch adsorption technique. The maximum removal rate was found as 451.7 mg UO2 2+·g−1 ZH. The adsorption capacity and adsorption rate of the calcinated products gradually decreases with increasing calcination temperature. The hydroxyl groups in the zirconium hydroxide play an important role for the adsorption uranyl ions, which agree well with the thermogravimetric analysis of zirconium hydroxide for completely dehydration at 700 °C. The observed data shows that the adsorption process is dependent on surface complexation mechanism.