FREMGANGSM}TE FOR RENSING AV PARTIKKELFORMIG KOBBERSULFID.

摘要

1418610 Purification of cupriferous sulphide material INTERNATIONAL NICKEL CO OF CANADA Ltd 3 July 1974 [5 July 1973] 29424/74 Heading C1A Cupriferous sulphide material, containing as impurity one or more sulphides of metals higher in the electromotive series (i.e. more electropositive) than copper, is purified by dissolving the impurity by heating a slurry of the particulate impure sulphide in an acidic aqueous solution containing sulphuric or hydrochloric acid or both in a total amount from 1 to 10 times that stoichiometrically necessary to react with the sulphide impurity to a temperature of 200-275‹ C. in a closed vessel under superatmospheric pressure and under an atmosphere non-oxidizing to the copper sulphide and non-reducing to the dissolved impurity metal and having a partial pressure of hydrogen sulphide of less than 0À1 atmosphere. The partial pressure of hydrogen sulphide formed during dissolution may be kept below 0À1 atmosphere by purging with an inert gas (optionally argon, nitrogen or steam) or with air in an amount insufficient to cause dissolution of the copper sulphide. The vessel may also be purged with air during the later stages of the dissolution. The impurities to be removed include Ni, Fe, Pb, Co, As and Zn.