Process to recover vanadium contained in acid solutions

A process to separate the vanadium dissolved in solutions containing sulfuric acid consisting of:

• a. Oxidizing all the vanadium present in solution or liquor to vanadium (V) by delivering an air current.
• b. Adding calcium hydroxide, quicklime or calcium carbonate.
• c. Separating the resulting solid, a mixture of vanadium pentoxide and calcium sulfate, by means of a physical method, solid-liquid separation.
• d. Dissolving the solid obtained in numeral ‘c’ in an acid different from sulfuric to obtain solid calcium sulfate and dissolved vanadium pentoxide.
• e. Separating the solid resulting in numeral ‘d’, calcium sulfate, with a physical method (solid-liquid separation).
• f. Precipitating the vanadium pentoxide by adding to the solution obtained in numeral ‘d’ solid sodium hydroxide.

A process for recovering vanadium from non-sulfuric acid inorganic acid solutions or liquors, comprising:

• a. oxidizing the vanadium present in the solution or liquor to vanadium (V);
• b. adding a neutralizing agent selected from the group consisting of calcium hydroxide, quicklime, calcium carbonate, and combinations thereof, to the solution or liquor;
• c. precipitating solid vanadium pentoxide from the solution or liquor;
• d. separating the solid vanadium pentoxide from the solution or liquor;
• e. converting the separated solid vanadium pentoxide to crystalline vanadium pentoxide by heating the solid vanadium pentoxide to a temperature from about 500 degrees to about 1400 degrees Celsius.

A process for recovering vanadium from solutions or liquors containing sulfuric acid comprising:

• a. oxidizing the vanadium in the solution or liquor to vanadium (V);
• b. adding to the solution or liquor a neutralizing agent selected from the group consisting of calcium hydroxide, quicklime, calcium carbonate or combinations thereof to form a precipitate of calcium sulfate and vanadium pentoxide;
• c. separating the vanadium pentoxide and calcium sulfate precipitate from the solution or liquor;
• d. adding an acid other than sulfuric acid to the vanadium pentoxide and calcium sulfate precipitate to obtain solid calcium sulfate and dissolved vanadium pentoxide;
• e. separating the solid calcium sulfate from the resultant solution obtained from step d;
• f. adding sodium hydroxide to the resultant solution;
• g. precipitating the vanadium pentoxide from the resultant solution;
• h. separating the precipitated vanadium pentoxide from the resultant solution.

A process for separating vanadium from non-sulfuric acid inorganic acid solutions containing oxidized vanadium, comprising:

• a. adding a neutralizing agent selected from the group consisting of calcium hydroxide, quicklime, calcium carbonate, and combinations thereof, to the solution;
• b. precipitating solid vanadium pentoxide from the solution;
• c. separating the solid vanadium pentoxide from the solution;
• d. converting the separated solid vanadium pentoxide to crystalline vanadium pentoxide by heating the solid vanadium pentoxide to a temperature from about 500 degrees to about 1400 degrees Celsius.

A process for recovering vanadium from sulfuric acid solutions containing oxidized vanadium comprising:

• a. adding to the solution a neutralizing agent selected from calcium hydroxide, quicklime, calcium carbonate or combinations thereof;
• b. separating solid vanadium pentoxide and calcium sulfate precipitate from the solution;
• c. adding an acid other than sulfuric acid to the solid vanadium pentoxide and solid calcium sulfate precipitate to obtain solid calcium sulfate and dissolved vanadium pentoxide in solution;
• d. separating the solid calcium sulfate from the resultant solution obtained from step c;
• e. adding sodium hydroxide to the resultant solution;
• f. precipitating solid vanadium pentoxide from the resultant solution;
• g. separating the solid vanadium pentoxide from the resultant solution.