<p>This study presents the development and experimental validation of an integrated technology for producing high-purity ammonium metavanadate (NH₄VO₃) from vanadium-containing technogenic raw materials contaminated with phosphorus and sulfur. Roasted spent vanadium catalysts from the petrochemical industry were used as the initial feedstock. </p><p>It was demonstrated that direct precipitation of vanadium from alkaline solutions using ammonium sulfate leads to significant co-precipitation of phosphorus and sulfur impurities into the target product. Therefore, preliminary purification of vanadium-containing solutions is required.</p><p>Two approaches for phosphorus removal were investigated: precipitation using magnesium oxide and aluminum sulfate. Magnesium oxide provided only partial phosphorus removal and was accompanied by vanadium losses due to co-precipitation. In contrast, treatment with aluminum sulfate reduced the phosphorus concentration in solution to 0.035 g/L, corresponding to a purification efficiency of approximately 90%.</p><p>Following deep purification, vanadium precipitation with ammonium nitrate enabled the production of ammonium metavanadate with phosphorus content below the detection limit and minimal sulfur content. The obtained product exhibits an orthorhombic crystalline structure and is suitable for the production of high-purity V₂O₅ and subsequent metallurgical applications.</p>