The influence of calcium, magnesium, phosphorus and silica on vanadium precipitation in acidic sulfate solutions

The experimental research work was carried out in accordance with the Facto rial Design Statistical Method to evaluate and analyze the influence of cal cium, magnesium, silica and phosphorus on the precipitation of vanadates, P recipitation was performed by neutralization with H2SO4 of alkaline aqueous solutions containing vanadium pentoxide (V2O5) at 60+/-2 degrees C. The ex perimental responses measured were percent of vanadium recovery and vanadiu m pentoxide content in the precipitate. These impurities are considered rep resentative of those present in a leach liquor from the ore obtained at Cam po Alegre de Lourdes (Brazil). The operational variables in this work were used under optimum conditions as determined by the statistical approach. Among the impurities under study, phosphorus exhibited the highest negative influence on the experimental responses. Phosphorus diminished the percent of vanadium recovered from 98.9 to 34.5 and the vanadium oxide content in the precipitate from 91.2 % to 39.3 %.