Rate of uranium adsorption on hydrous titanium (IV) oxide granulated with poly acrylic hydrazide.

Abstract

Three kinds of granulated hydrous titanium oxides (HTiOs) with different particle size (100 ∼ 120, 42 ∼ 60 and 32 ∼ 35 mesh size) were prepared by using poly acrylic hydrazide (PAH) as a binder. Rates of U adsorption on native HTiO powder and the granulated HTiOs were measured from U-enriched sea water by batchwise method. The intraparticle diffusivity (Dp ) of U was evaluated by using the model of pore, diffusion with Freundlich-type adsorption isotherm. The estimated diffusivity (Dp ) was 1.07 × 10−6 cm2/s for the HTiO powder. Its tortuosity factor calculated by parallel plate pore model was 1.6. Although the granulated HTiOs had macropores around 2,000 nm in radius in addition to the mesopores originated from HTiO powder, they showed smaller Dp values (3.0 × 10−7 ∼ 8.6 × 10−7 cm2/s) than the native HTiO. The smaller Dp values of the granulated HTiOs may be due to the influence of the PAH which adheres on the HTiO particles.