ISOELECTRIC POINTS FOR NIOBIUM AND VANADIUM PENTOXIDES

Abstract
The isoelectric points for niobium and vanadium pentoxide were determined through electrophoretic measurements and the experimental results were compared with three alternative procedures to predict this parameter. Experimental and predicted results show good agreement for Nb2O5 that presents a well defined value for the isoelectric point but they do not correlate well in the case of V2O5 that present a rather high solubility in the isoelectric pH region.