Polyhydrated phases in the exchange of H+ and K+ in α-titanium phosphate

Abstract

The exchange of H⁺ by K⁺ in α-titanium phosphate, Ti(HPO₄)₂·H₂O, was studied. The exchange isotherm and the hydrolysis and titration curves were obtained, and the evolution of the material was followed by X-ray diffraction. The existence of partially substituted phases was not detected. Phases saturated in potassium and highly hydrated, Ti(KPO₄)₂·3H₂O (interlayer distance 10.4 Å) and Ti(KPO₄)₂·2H₂O (9.6 Å), were obtained. The experimental results are explained by taking account of the structures of the materials.