Kangkang Yuan

Characterization and adsorption mechanism of ZrO 2 mesoporous fibers for health-hazardous fluoride removal

One-dimension ZrO2 mesoporous fibers were successfully synthesized by utilizing the electrospinning device combining with the soft-template method. The morphology and composite of the fibers were characterized by XRD, SEM, TEM, FT-IR, TGA/DSC and XPS, and the pore structure and surface area were calculated according the BET measured results. The fluoride adsorption performance of the fibers was investigated and the adsorption capacity was upto 297.70 mg g-1. Moreover, the equilibrium concentration could be reached to 1.41 mg L-1 with the initial of 30 mg L-1, and the removal rate could be reached to 95.3%. The adsorption data were well fitted with the Freundlich isotherm model and pseudo-second-order kinetic model. The fibers had a good reusability and long-term utilization for fluoride adsorption. All the results suggested that the as-prepared ZrO2 mesoporous fibers with high surface area could be an excellent adsorbent for the wastewater defluoridation treatment.

Effects of atmosphere and stabilizer on the decomposition and crystallization of polyacetylacetonatozirconium

The present study fully reports the decomposition of polyacetylacetonatozirconium (PAZ) in air with thermogravimetry–differential scanning calorimetry and Fourier transform infrared spectroscopy. The influence of water vapor on the decomposition of PAZ was characterized with the Fourier transform infrared spectroscopy. Crystallization and phase transformation of PAZ were studied by X-ray diffraction and Raman spectroscopy. The experimental results show that water vapor promotes the decomposition of PAZ and crystallization of zirconia compared with air. Furthermore, the effect of different amount of stabilizer Y(NO3)3·6H2O on the pyrolysis and phase stabilization of PAZ shows that NO3− was beneficial to the oxidation of organic components and the formation of Y2O3 could stabilize tetragonal zirconia and hinder grain growth.