The Extraction of Copper Chemistry LibreTexts
The iron in the chalcopyrite ends up converted into an iron(II) silicate slag which is removed. Most of the sulfur in the chalcopyrite turns into sulfur dioxide gas. This is used to make sulfuric acid via the Contact Process. An overall equation for this series of steps is: [2CuFeS_2 + 2SiO_2 +4O_2 rightarrow Cu_2S + 2FeSiO_3 + 3SO_2 label{1} ]