The paper presents a new, nonconventional method, based upon coprecipitation, for the synthesis of niobium oxidic compounds.
The coprecipitation product of niobic acid with calcium oxalate was used as precursor. Calcium metaniobate was obtained by
appropriate thermal treatment of the coprecipitate. The coprecipitation mechanism was studied and the optimal conditions for
quantitative precipitation of niobium and calcium were established. The mechanism of thermal decomposition of the coprecipitate
was investigated by means of differential thermal analysis and X-ray powder diagrams. The final product of thermal decomposition,
calcium metaniobate, is formed at 730°C.