A new amorphous phase of stannic phosphor–silicate

Autor: K. G. Varshney, S. D. Sharma, S. C. Mojumdar
Rok vydání: 2014
Předmět:
Zdroj: Journal of Thermal Analysis and Calorimetry. 119:837-844
ISSN: 1588-2926
1388-6150
Popis: Sixteen samples of a new phase of stannic phosphor–silicate inorganic ion exchanger have been synthesized under different conditions of preparation. The sample possessing the maximum ion-exchange capacity (1.50 meq g−1 of dry exchanger) was chosen for the detailed study and its chemical composition was determined. The new phase is found to be thermally stable, possessing a high ion-exchange capacity, and showing an interesting regeneration phenomenon after heating at elevated temperatures when compared to the corresponding ion exchanger stannic phosphate. The ion-exchange capacity is found to be almost completely regained when determined on regenerated samples. The gain/loss of ion-exchange capacity has been studied as a function of temperature, in the range of 40–800 °C. Thermo gravimetric (TG) analysis, X-ray, pH titrations and IR spectral studies have been performed. TG of the exchanger shows a higher percent mass loss in H+ form than that in the K+ form. Thermal studies give an idea of the internal and the external water molecules present in the exchanger. On this basis, the empirical formula of the new phase of the stannic phosphor–silicate prepared in these studies has been proposed. Quantitative separation of UO 2 2+ from VO2+ and Zn2+, and that of Cu2+ from Al3+ and Ni2+ have been achieved on the basis of its adsorption behaviour. The reproducibility in the properties of the exchanger has been checked by duplicate preparations.
Databáze: OpenAIRE
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