Application of Titanium Dioxide for Zirconium Ions Adsorption and Separation from a Multicomponent Mixture

This work studies the adsorption of zirconium ions by mesoporous titanium dioxide and by sodium-modified mesoporous titanium dioxide. Experimental maximal adsorption values of zirconium ions by H-TiO2 and Na-TiO2 were found to be 64 mg/g and 109,5 mg/g respectively. This process depends on the interaction time, equilibrium concentration of zirconium ions and acidity of the solution. Adsorption kinetics fit well into the diffusion kinetic model and indicate a several stages of zirconium ions adsorption. Equilibrium adsorption of zirconium ions is well described by the Langmuir's adsorption theory for both adsorbents. The results obtained by inductively coupled plasma mass spectrometry showed that the investigated adsorbent selectively adsorb zirconium ions from the mixture with strontium and yttrium ions in the range of solution pH = 0-1. The percentage of maximum extraction of zirconium ions is 86,61% for H-TiO2 and 94,11% for Na-TiO2. This fact is extremely valuable for nuclear forensics or for the determination of 90Sr in low activity background samples.

Synthesis and Photocatalytic Properties of Three-Dimensional Mesoporous Titanium Dioxide

The three-dimensional (3D) mesoporous titanium dioxide (TiO2) was synthesized by microwave-assisted hydrothermal method, using titanium sulfate as titanium source and urea to adjust pH value. Its structure and photocatalytic oxidation properties were studied. The results show that the TiO2 particles have a 3D mesoporous structure, uniform distribution and spherical shape, the average diameter is about 0.67[Formula: see text][Formula: see text]m. These properties provide strong light adsorption, high specific surface area, which increases the active site of the photocatalyst, porosity can also enhance the ability of the material to adsorb pollutants, thus has better stability. It was applied to photocatalytic degradation of 10[Formula: see text]mg/L rhodamine B (RhB) solution. After 80[Formula: see text]min of irradiation under 420[Formula: see text]nm ultraviolet (UV) light, the degradation rate of RhB reached more than 90%. In addition, it also provided an excellent photocatalytic efficiency of removing Hg0 in simulated flue gas. The removal efficiency could still reach over 86% after 40 h, which could be used in the treatment of heavy metal pollutants such as metallurgical flue gas.