Abstract: Disclosed is a pyrometallurgical process for producing a crude solder comprising at least 9.5-69% wt of tin and at least 25% wt lead, at least 80% tin and lead together, 0.08-12% wt of copper, 0.15-7% wt of antimony, 0.012-1.5% wt of bismuth, 0.010-1.1% wt of zinc, at most 3% wt of arsenic, at most 2.8% wt of nickel, at most 0.7% wt of zinc, at most 7.5% wt of iron and at most 0.5% wt of aluminium, from a feedstock selected in terms of its levels of Sn, Cu, Sb, Bi, Zn, As, Ni and Pb, the process comprising at least the steps of obtaining in a furnace a liquid bath of metal and slag, introducing a reducing agent and optionally also energy, separating the crude solder from the slag and removing liquid from the furnace. The crude solder may readily be further prepared to become suitable as feedstock for vacuum distillation.

Abstract: Disclosed is a pyrometallurgical process for producing a crude solder from a feedstock selected in terms of its levels of Sn, Cu, Sb, Bi, Zn, As, Ni and Pb, the process comprising at least the steps of obtaining in a furnace a liquid bath of metal and slag, introducing a reducing agent and optionally also energy, separating the crude solder from the slag and removing liquid from the furnace. Further disclosed is a crude solder comprising at least 9.5-69% wt of tin and at least 25% wt lead, at least 80% tin and lead together, 0.08-12% wt of copper, 0.15-7% wt of antimony, 0.012-1.5% wt of bismuth, 0.010-1.1% wt of zinc, at most 3% wt of arsenic, at most 2.8% wt of nickel, at most 0.7% wt of zinc, at most 7.5% wt of iron and at most 0.5% wt of aluminium. The crude solder may readily be further prepared to become suitable as feedstock for vacuum distillation.