Process for extracting of vanadium pentoxide by water immersion from cured mixture of stone coal ash with surfuric acid by heating

Process of extracting V205 from bone coal ash which is difficult to oxidize includes: ash is mixed with sulfuric acid, and is slaked at 100-250-deg.C for 1-3hr. in fluidizing reactor;after immersion with water, solid-liquid separation, crystallization of potassium alum and ammonium alum, reduction, extraction, back-extraction, oxidation precipitation of vanadium and calcination a product of V205 is obtd. The overall recovery rate of V205 is over 62%. By the process of this invention 10 tons of pure potassium alum and 55 tons of pure ammonium alum may be recovered for prodn. of one ton of V205.