Process for the Precipitation of Metal Values from Solutions (Patent No: 642918)

Inventor: Kunda, Vasyl

Location: Fort Saskatchewan

Comments: see Sherritt Gordon

Description:

The embodiments of the invention in which an exclusive property or privilege is claimed, are defined as follows:

1. The method of separating values of metals which form insoluble sulphides more readily than nickel in acid and neutral solutions which contain, in solution, at least one salt of a metal selected from the group consisting of nickel and cobalt, and a salt of at least one metal which forms an insoluble sulphide more readily than nickel which comprises the steps of reacting said solution at a pH value within the range of from about pH 1 to about pH 7 with sulphur dioxide and finely divided particles of elemental sulphur in excess of the stoichiometric equivalent of sulphur required to combine with said first mentioned metal values to form metal sulphides, actively agitating the solution in an inert atmosphere at a temperature above about 125°F., continuing said reaction to form and precipitate said insoluble metal sulphides, and separating precipitated metal sulphides from the solution.

2. The method according to claim 1 in which the pH value of the solution is adjusted to within the range of from about pH 1 to about pH 7 prior to the initiation of sulphidizing reaction.

3. The method according to claim 1 in which elemental sulphur in about the stoichiometric amount required to combine with the values of the metals which form insoluble metal more readily than nickel is provided in the solution.


4. The method according to claim 1 in which the added elemental sulphur is of a particle size smaller than about 104 microns.


5. The method according to claim 1 in which the elemental sulphur is treated with a finite amount of a wetting agent prior to its dispersion in the solution.


6. The method according to claim 1 in which the reaction is conducted at a temperature above about 180°F.


7. The method according to claim 1 in which the sulphur dioxide is formed in the solution by the addition to the solution of a soluble metal sulphite.


8. The method according to claim 1 in which the sulphur dioxide is formed in the solution by the addition to the solution of a soluble metal sulphite selected from the group consisting of ammonium sulphite and sodium sulphite.