Patent ID: 6652819
Filing Date: 2003-11-25
Classification: C01G,C22B,H01M,Y02E,Y02P

Abstract:
A process for the production of a vanadium compound from carbonaceous residues containing at least about 20% by weight of carbon and at least about 1% by weight of vanadium, comprising the steps of:(a) combusting said carbonaceous residues at a temperature of 500-690Â° C. using an oxygen-containing gas to form vanadium-containing combustion residues; (b) heating said vanadium-containing combustion residues at a temperature T in Â° C. under an oxygen partial pressure of at most P in kPa wherein T and P meet with the following conditions: log10(P)=âˆ’3.45Ã—10âˆ’3Ã—T1+2.21 500&lE;T&lE;1300 to obtain a solid product containing less than 5% by weight of carbon and vanadium at least 80% of which is tetravalent vanadium oxide;(c) mixing said solid product with water and sulfuric acid to form a mixture and to selectively leach tetravalent vanadium ion while maintaining the pH of said mixture in the range of 1.5-4; (d) separating a liquid phase from said mixture; (e) adding an alkaline substance to said liquid phase to adjust the pH thereof in the range of 4.5-7.5 and to selectively precipitate vanadium ion as a tetravalent vanadium compound; and (f) separating the precipitates obtained in step (e).