Preparation of V2O5 from Ammonium Metavanadate via Microwave Intensification

Resumo

Parameters of technique to prepare of V₂O₅ by microwave intensification from ammonium metavanadate were optimized using central composite design of response surface methodology. A quadratic equation model for decomposition rate was built and effects of main factors and their corresponding relationships were obtained. The microwave heating behavior indicated that ammonium metavanadate had weak capability to absorb microwave radiation, while V₂O₅ had good capability to absorb microwave radiation. The results of the statistical analysis showed that the decomposition rate of ammonium metavanadate was significantly affected by calcination temperature and calcination time in the range studied. The optimized conditions were as follows: calcination temperature 645.35 K, calcination time 9.66 min and 4.3 g, respectively. The decomposition rates of ammonium metavanadate were 99.13%, which coincided well with experiments values 99.33% under these conditions. These suggest that regressive equation fits the decomposition rates perfectly. XRD reveals that it is feasible to prepare the V₂O₅ by microwave intensification from ammonium metavanadate, which mixed with small amounts of V₂O₅.