The alkaline leachate
of the roasted concentrate was subjected to the precipitation of silica and
alumina; it was then left to stay overnight to allow the crystallization of
sodium sulfate as a purification step. The filtrate was divided into two parts;
the first was used for the direct precipitation of vanadium, whereas the second
was used for the ion-exchange separation.
Precipitation of silica and alumina
leachate of the roasted titanium concentrate of 79%TiO2 has pH