Green recovery of vanadium from spent vanadium catalyst from sulfuric acid production

Research on extracting secondary raw materials from hazardous waste is gaining global importance. Spent catalysts containing heavy metals pose a great threat to environment. A key example is spent catalysts from sulfuric acid production, which contain 4.66% V₂O₅. This work aims at recovering vanadium from spent catalyst discharged from sulfuric acid industry. Experiments used four different leaching acids: tartaric acid, oxalic acid, acetic acid, and citric acid. The effects of temperature, reagent concentration, leaching duration, and solid/liquid (S/L) ratio were tested. Under optimal conditions, an impressive 95% of vanadium was recovered through citric acid leaching, with the following parameters (2% S/L ratio, 1 M citric acid, 70 °C, pH, and a leaching duration of 120 min). Results indicated the potential for recovering vanadium pentoxide from spent vanadium catalysts used in the sulfuric acid industry in Egypt.