Analysis of water leaching and transition processes in zirconium oxychloride octahydrate production

Abstract

The water leaching and transition process in manufacturing zirconium oxychloride octahydrate was examined. Results from X-ray diffraction (XRD) and Fourier-transform infrared (FT-IR) spectra showed that most of the soluble sodium silicate was dissolved and the residue hydrolyzed into H2SiO3 during the water leaching process. In addition, Na+ from sodium zirconate (NaZrO3) in the interlayer was removed during the first and second water leaching and the in-host layer was distinguished in the third water leaching. This process resulted in the hydrolysis of NaZrO3 into ZrO(OH)(2). Results from the scanning electron microscopy (SEM), FT-IR spectra, nuclear magnetic resonance (NMR) and XRD of the transition process showed the main reaction and properties of the products at different pH values. Na2ZrSiO5 reacted with HCl at pH=7, producing ZrO(OH)(2) SiO2 and NaCl. ZrO(OH)(2) SiO2 partially reacted with HCl, forming ZrOCl2 and H2SiO3 with a decrease in pH. (C) 2013 Elsevier Ltd and Techna Group S.r.l. All rights reserved.