Ion-exchange Properties of Zn4(OH)6(SO4) 2.5H2O

The aim of the present study is to check the possibilities for ion exchange of a new zinc-hydroxy-sulfate-hydrate phase, Zn4(OH)6SO4·2–2.25H2O. The new zinc hydroxy sulfate hydrate phase was obtained by mixing of 0.5 g of Zn5(OH)8(NO3)2.2H2O and 50 ml of 1M Na2SO4 for 48h at room temperature and pH of the solution between 5–7. Ion-exchange properties were investigated by mixing of 0.2 g Zn4(OH)6(SO4) 2.5H2O with 20 ml water solution of NaCl, CaCl2 or SrCl2 with different concentrations (0.5М, 1М, or 2M) for different time (24h, 48h and 72h) at room temperature. The pH of the solutions varied in the range 6–8. The new phase has exchange properties potentials, like other zinc hydroxy sulfate hydrates composed of octahedral-tetrahedral layers. The results obtained for the kinetics of ion-exchange reactions are additional useful data for the solving of the structure of the new zinc-hydroxy-sulfate-hydrate phase in the future.