Synthesis, Characterization and Application of a Derivatized Acidic Salt of a Tetravalent Metal. Pyridine Anchored on to Tin(IV) Tungstoselenate

Abstract

The inorgano-organic ion-exchanger, tin(IV) tungstoselenate–pyridine, has been prepared by derivatizing the inorganic ion-exchange material, tin(IV) tungstoselenate, with an organic moiety, pyridine. Chemical studies showed the tin(IV) tungstoselenate/pyridine mole ratio to be 806.5:1, indicating a weak sorption of pyridine on to the surface of the tin(IV) tungstoselenate. The material was characterized on the basis of SEM, FT-IR, TGA and DTA studies. The uptake of Cu2+, Ni2+, Fe2+ and Fe3+ ions was found to be much higher on tin(IV) tungstoselenate–pyridine relative to tin(IV) tungstoselenate. The uptake of these metal ions as a function of loading and pH was also studied when the following affinity order was observed: Cu2+ > Co2+ > Ni2+ > Fe2+ > Fe3+. The uptake of metal ions increased initially with loading but became constant at higher loading. The most favourable pH range was found to be that between 3.5 and 4.5.