Mechanisms of Oxidation and Vaporization of Antimony from Liquid Copper with CuCl–CaO Fluxes
Yang Cui, Hiroyuki Matsuura, Tasuku Hamano, Fumitaka Tsukihashi
In order to clarify the reaction mechanisms of oxidation and vaporization of Sb in liquid copper by using CuCl–CaO fluxes, the vaporization behavior from CuCl–Sb2O3 and CuCl–CaO–Sb2O3 fluxes and the reaction behavior of Cu2O between CuCl–Cu2O flux and liquid copper were observed at 1423 K with argon gas.
For the vaporization from CuCl–Sb2O3 and CuCl–CaO–Sb2O3 fluxes, SbCl3 and SbOCl in flux were observed in the fluxes, and these chloride and oxychloride vaporized to gas phase.
In the reaction between CuCl–Cu2O and liquid copper, the decomposition of Cu2O in the flux was confirmed, and the copper weight and oxygen content of copper increased.
The mechanisms of oxidation and vaporization of antimony in liquid copper by using CuCl–CaO fluxes were discussed based on the observed results. The Cu2O existing in CuCl–CaO flux is dissolved in copper melt, and the oxygen content of copper increases. The antimony in liquid copper is oxidized and removed to slag phase as Sb3+. The formed Sb3+ in flux vaporizes from flux as SbCl3 and SbOCl.