Treatment of Nickel Containing Matte or the Like Material to Remove Molybdenum (Patent No: 892476)

Inventor: Mehl, Ernest

Location: Fort Saskatchewan

Comments: N/A

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

1. A process for treating nickel, iron and sulphur containing mattes, intermediates and residues which feed material also contains molybdenum as a contaminant to remove said contaminant therefrom which comprises the steps of: mixing finely divided particles of said material with an alkali provided in an amount equivalent to a feed material to sodium hydroxide in the weight ratio in the range of from about 20:1 to about 3:1; adding sufficient water to the mixture of the said material and said alkali to encourage and promote the agglomeration of said mixture into pellets, pelletizing said mixture, roasting the resulting pellets at a temperature within the range of about 1000°F. to about 1600°. in contact with oxygen for a time sufficient to convert substantially all said molybdenum values into soluble alkali metal molybdates, quenching said roasted pelletized mixture in water and agitating the resulting slurry to extract and dissolve the soluble molybdenum values in solution; separating the solution from residue, and recovering said residue and contained nickel values substantially free from molybdenum contamination.

2. The process as claimed in claim I wherein up to 80% by weight of the quantity of alkali mixed with said material is mixed in a dry state and the balance of said alkali is dissolved in the water which is added to said mixture to encourage and promote the agglomeration of said mixture into pellets.

3. The process as claimed in claim 2 wherein said alkali is selected from the group comprising sodium hydroxide, sodium carbonate, sodium sulphide, potassium hydroxide, potassium carbonate and mixtures thereof.

4. The process as claimed in claims 1, 2 or 3 wherein said pelletized mixture is roasted in air at a temperature of about

5. The process as claimed in claims 1 or 2 wherein said pelletized mixture is roasted in air at a temperature of about l400°F. for a period of from about 30 minutes to about 120 minutes.

CLAIM SUPPORTED BY THE SUPPLEMENTARY DISCLOSURE

6. The process according to claims 1, 2 or 3 wherein the oxygen requirements for the pellet roasting step are provided by contacting the pellets with steam during roasting.