Hydrothermal synthesis and characterization of the layered zirconium germanate Na2Zr5Ge2O15 center dot nH(2)O

A layered sodium zirconium germanate of formula Na2Zr5Ge2O15. nH(2)O isostr uctural to the layered Na2Zr5Si2O15. O-15. nH(2)O and Zr2O3(HPO4). nH(2)O ( Psi-zirconium phosphate) was synthesized hydrothermally. Its protonic form H2Zr5Ge2O15. nH(2)O was prepared by acid treatment of the initial compound. The properties of these compounds were determined by means of physical and chemical methods, including X-ray diffraction, thermal analysis, IR and sc anning electron microscopy. The layered nature of the compound was confirme d by amine intercalation reactions. The ion exchange behavior of the zircon ium germanate towards alkali and alkaline-earth ions was studied over a wid e pH range (2-14) by the batch technique.