Process for the production of crude solder

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.

Dependencies are inferred from the claim text.