Abstract: A process for removing the impurities, such as arsenic, antimony, bismuth, and/or lead, from a metal sulfide melt, such as copper sulfide melt, in which there is a melt solubility gap between the metal to be refined and its sulfide, in which the metal sulfide melt is first sulfidized in order to shift the composition of the melt away from the range of the solubility gap and the sulfidized metal sulfide melt is thereafter exposed to a selective chlorination to remove the impurities as vaporizable chlorides from the metal sulfide melt by a technique known per se, while the sulfur concentration in the melt is simultaneously controlled in such a manner that the composition of the melt remains outside the said melt solubility gap.

Abstract: In a process for purifying carboniferous iron, nickel and/or cobalt alloys in which the base metal tends to form a carbide, a mixture of at least one halogen and hydrogen is added to the metal melt in order to remove in the form of halides the metals present as impurities.