METHOD FOR RECOVERING HIGH PURITY VANADIUM

摘要

PROBLEM TO BE SOLVED: To provide a method of wet process for recovering a high purity vanadium with a sulfur content of 0.1% or less from a petroleum-based incineration ash.

SOLUTION: The method contains: a first process of adding an acid and a reducing agent to a mixture liquid of a petroleum-based incineration ash and water to thereby render a pH of the above mixture liquid to be 2-3 and to separating and removing a solid matter from the above mixture liquid while regulating an ORP to be 200-400 mV; a second process of adding an alkali and a reducing agent to the solution after the separation and removal of the above solid matter to thereby render the pH of the above solution to be 5-7 and of separating a solid matter by precipitating a vanadium ion while regulating the ORP to be -100 to 100 mV; the third process of dissolving the above separated solid matter in hydrochloric acid with a concentration of 30-35% and of continuously infusing a reducing agent in the above solution and moreover of adding an alkali and regulating the pH to be 5.5-6.5 to thereby recrystallize it; and a fourth process of washing with water the crystallized vanadium- containing crystal and thereafter of dehydrating it and collecting V2O4or V2O4-2H2O of a high purity.

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