Method for extracting valuable metals from petroleum ash through sodium salt roasting

The invention discloses a method for extracting valuable metals from petroleum ash through sodium salt roasting. According to the method, firstly vanadium and nickel are separated from each other through sodium salt roasting; vanadium is converted into soluble sodium vanadate; sodium vanadate solution is obtained through leaching of water; high-purity ammonium metavanadate is obtained through purification and vanadium precipitation; nickel, in a form of nickel matte, is kept in reaching residues, and can be used for the further production of nickel products. The technology has the advantages that vanadium and nickel are separated from each other, and high-purity vanadium products and nickel matte can be obtained.