Method for recovering vanadium from residues from the combustion of petroleum fractions
AssigneeEnte Minerario Siciliano
InventorsFrancesco Corigliano, Sebastiana Di Pasquale, Patrizia Primerano, Cesare Zipelli
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Abstract
A method is described for recovering vanadium from residues from the combustion of petroleum fractions, wherein the residues, such as ash and soot, are leached with aqueous H.sub.2 SO.sub.4 to extract vanadium and any additional polyvalent cations contained therein. The acid leaching solution, after oxidation of the extracted cations, is treated with a complexing agent, in particular EDTA or salts thereof, and then with ammonia to selectively precipitate vanadium as highly pure ammonium polyvanadate.
Claims10
Method for recovering vanadium from the residues from the combustion of petroleum fractions, comprising:
- (i) extracting vanadium together with other polyvalent cations contained in said residues which interfere with the vanadium recovery by acid leaching of said residues whereby obtaining a solution of said vanadium and said interfering cations, and
- (ii) treating the resulting acid solution with an oxidizing agent for vanadium and said interfering cations, wherein said method further comprises
- (iii) adding to said acid solution from (ii) containing oxidized vanadium and interfering cations a complexing agent able to selectively form soluble complexes with the oxidized interfering cations, and
- (iv) adding to said solution ammonia at a pH of 1.7-2.3 and heating to 70.degree.-100.degree. C., whereby the uncomplexed vanadium is selectively precipitated as ammonium polyvanadate in a form substantially free of said interfering cations.
Method for recovering vanadium from the residues from the combustion of petroleum fractions, comprising:
- (i) extracting vanadium together with other polyvalent cations contained in said residues which interfere with the vanadium recovery by acid leaching of said residues whereby obtaining a solution of said vanadium and said interfering cations, and
- (ii) treating the resulting acid solution with an oxidizing agent for vanadium and said interfering cations, wherein said method further comprises
- (iii) adding to said acid solution containing oxidized vanadium and interfering cations a complexing agent selected from ethylenediaminetetraacetic acid and salts thereof, said complexing agent selectively forming soluble complexes with the oxidized interfering cations, and
- (iv) adding to said solution ammonia at a pH of 1.7-2.3 and heating to 70.degree.-100.degree. C. so as to selectively precipitate the uncomplexed vanadium as ammonium polyvanadate in a form substantially free of said interfering cations.
Dependencies are inferred from the claim text.