Preparation,characterisation and thermal decomposition of barium zirconyl oxalate

Barium zirconyl oxalate hydrate (BZO) is prepared and characterised by chemical analysis and IR spectral studies. Thermal decomposition studies have been made using TG and DTA techniques. The decomposition has been found to proceed through four steps. The first step involves a two-stage dehydration (100–190°C, 190–260°C) and the second step the decomposition of oxalate (260–460°C). The third step involves the evolution of carbon monoxide present in the lattice and partial decomposition of carbonate. The fourth step involves the final stage decomposition of carbonate (760–920°C) giving barium zirconate as an end product. The identification of compounds at various stages has been done by IR spectra. The X-ray diffraction pattern of BZO confirms that it is a crystalline compound.