Cation exchange and sorption properties of TIN(IV) phosphate

The ion exchange and sorption properties of crystalline Tin bis(monohydroge n orthophosphate) monohydrate of composition Sn(HPO4)(2). H2O were studied in an aqueous solution of KCI over the temperature range 300-320 K, varying the pH and metal ion concentration in the solution. The data were explaine d on the basis of the law of chemical equilibrium. The metal ion sorption d ata were fitted to the Langmuir adsorption equation to evaluate the Langmui r parameters. The extent of adsorption was found to increase with an increa se in temperature and metal ion concentration in the selectivity order Cu2 > Co2+ > Ni2+. The Langmuir parameters were used to calculate the thermody namic functions like standard entropy, enthalpy, and free energy changes du ring the process Of sorption, (C) 2000 Academic Press.