Synthesis and Characterization of Novel Highly Crystalline Layered Nanosized Zirconium-, Hafnium-, Titanium Tellurates from Their Parent Glassy Sodium Forms via HF Solution

Document Type : Original Article

Authors

1 Department of Chemistry, Faculty of Science, Tripoli University, P.O.Box 13203, Tripoli, Libya.

2 Industrial research centre, Tripoli, Libya.

10.18576/jpac/020312

Abstract

Glassy zirconium-, hafnium-, titanium tellurates were prepared and characterized. Found to be amorphous with vitreous visual look. Their general formulae were MO(HTeO4)2.nH2O ( where M=Zr, Hf, Ti , n =3.35, 3.22 , 3.99),
respectively. Novel crystalline layered nanosized ZrO(HTeO4)2.3.72H2O, HfO(HTeO4)2.2.98H2O and
Ti(TeO4)(HTeO4)2.3.89H2O of high degree of crystallinity, were prepared from crystallization of their parent glassy
sodium forms with HF solution in Pyrex round bottom flask. They were characterized by chemical; X-ray diffraction (XRD), thermal gravimetric analysis (TGA) and Fourier transform spectroscopy (FT-IR). Their exchange capacities were determined. We think these materials crystallized during the conversion process in two steps: 1st their parent glassy sodium forms dissolved in HF solution forming a Miv Fluoride complex, 2nd the crystalline products were gradually precipitated due to HF solution action on the Pyrex flask and to a certain extent evaporation of excess HF. This will explain the formation of high degree of crystallinity of the resulting layered materials. These materials can be considered new inorganic ion exchangers, proton conductance and as solid acid catalysts.

Keywords