SYNTHESIS OF LEAD METANIOBATE BY THERMAL-DECOMPOSITION OF A COPRECIPITATION PRODUCT

The paper reports a new, nonconventional method for the preparation of oxygen-containing niobium compounds, based upon coprecipitation. The coprecipitation product of niobic acid with lead oxalate was used as p recursor. Lead metaniobate was obtained by proper thermal treatment of the coprecipitate. The coprecipitate mechanism was studied and the op timal conditions for quantitative precipitation of niobium and lead we re established. The mechanism of thermal decomposition of the coprecip itate was investigated by differential thermal analysis and X-ray powd er diagrams. The final product of thermal decomposition, lead metaniob ate, is formed at 850 degrees C.