Ion Exchange Properties of Zirconium Molybdate and Zirconium Tungstate-I

Department of Chemistry, D. B. S. College, Dehradun

Department of Chemistry, University of Delhi, Delhi

Manuscript received 18 September 1979, accepted 30 December 1979

Zirconium molybdate and tungstate were obtained by adding aqueous solution of zirconium oxychloride to aqueous solutions of ammonium molybdate and sodium tungstate. pH-metric studies reveal that both the materials exhibit ion exchange properties. The thermogravimetric analysis of the samples indicate that both the exchanger materials contain about 11-12% of hydrated water which is released slowly within the temperature range 90 to 240° in case of zirconium molybdate and within 80 to 180° in the case of zirconium tungstate. The sorption of ammines of Zn(II), Cu(II), Cd(Il) and Ni(II) on the above exchangers have been studied at different ionic concentrations of the external solutions. In each case the sorption increases with increase in the external concentration (0.01 to 0.10 M), attains a maximum at 0.10111 and then decreases with further increase in the concentration. The sorption capacity, q_A, follows the order :

Zn(ll)-ammine > Cn(II)-ammine > Cd(II)-ammine > Ni(ll)-ammine.