Investigation of Reducing Magnetite in Copper Slag Using CO–CO₂

In this paper, CO is used as reductant in the process of copper slag cleaning, which can reduce the Fe₃O₄ content and improve the settling environment of copper in slag. The results showed that the Fe₃O₄ content and converter slag viscosity decrease with the increase in reduction temperature and time. The system temperature and reduction time have important effects on the CO utilization ratio. According to the variation of Fe₃O₄ reduction degree, the kinetic of the reduction process between CO and Fe₃O₄ at 1250–1350 °C was studied. It was found that the \([-\text{ln}\left(1-X\right){]}^\frac{2}{3}=kt\) $[-\text{ln}\left(1,-,X\right){]}^{\frac{2}{3}}=kt$ accords with the kinetic equation of cleaning process of copper slag by CO. The apparent activation energy of reaction process was 313 kJ/mol, and the reaction rate was controlled by the interface chemical reaction.