Extraction of Vanadium from High Phosphorus Vanadium Containing Waste Residue via Carbonation: Optimization Using Response Surface Methodology

Vanadium (V) was successfully extracted from a high phosphorus vanadium residue (HPVR) through a carbonation process. Vanadium within HPVR substitutes for Fe in the mineral structure of Ca9(Fe,V)(PO4)7 at elevated temperatures, Na2CO3 reacts with V to form sodium metavanadate (NaVO3), concurrently generating calcium carbonate (CaCO3) through its interaction with Ca9(Fe,V)(PO4)7. Subsequently, V is liberated and leached by water, dissolving in the aqueous phase as metavanadate ions (VO3−). Crucial factors influencing V leaching efficiency include roasting time, roasting temperature, and the amount of Na2CO3 utilized. Response Surface Methodology (RSM) was employed. The optimized parameters determined were as follows: a roasting temperature of 850 °C, a roasting duration of 120 min, a Na2CO3 dosage of 8.01%, a liquid-to-solid ratio (L/S) of 3, and a leaching time of 60 min. Under these conditions, a remarkable V leaching efficiency of 83.82% was achieved. This study underscores the viability of a simplified approach for treating solid waste containing metal slag, which not only mitigates environmental pollution but also yields valuable metals.