1 research outputs found
As(III) and As(V) Adsorption by Hydrous Zirconium Oxide Nanoparticles Synthesized by a Hydrothermal Process Followed with Heat Treatment
No full textHydrous zirconium oxide (ZrO<sub>2</sub>·<i>x</i>H<sub>2</sub>O) were synthesized by a low-cost hydrothermal process followed with heat treatment. ZrO<sub>2</sub>·<i>x</i>H<sub>2</sub>O nanoparticles ranged from 6 nm to 10 nm and formed highly porous aggregates, resulting in a large surface area of 161.8 m<sup>2</sup> g<sup>–1</sup>. The batch tests on the laboratory water samples demonstrated a very high degree of As(III) and As(V) removal by ZrO<sub>2</sub>·<i>x</i>H<sub>2</sub>O nanoparticles. The adsorption mechanism study demonstrated that both arsenic species form inner-sphere surface complexes on the surface of ZrO<sub>2</sub>·<i>x</i>H<sub>2</sub>O nanoparticles. Higher arsenic removal effect of these ZrO<sub>2</sub>·<i>x</i>H<sub>2</sub>O nanoparticles were demonstrated, compared with commercially available Al<sub>2</sub>O<sub>3</sub> and TiO<sub>2</sub> nanoparticles. Ionic strength and competing ion effects on the arsenic adsorption of these ZrO<sub>2</sub>·<i>x</i>H<sub>2</sub>O nanoparticles were also studied. Testing with natural lake water confirmed the effectiveness of ZrO<sub>2</sub>·<i>x</i>H<sub>2</sub>O nanoparticles in removing arsenic species from natural water, and the immobilization of ZrO<sub>2</sub>•xH<sub>2</sub>O nanoparticles on glass fiber cloth minimized the dispersion of nanoparticles into the treated body of water. The high adsorption capacity of ZrO<sub>2</sub>·<i>x</i>H<sub>2</sub>O nanoparticles is shown to result from the strong inner-sphere surface complexing promoted by the high surface area, large pore volume, and surface hydroxyl groups of zirconium oxide nanoparticles
