Kinetics of chlorination process of copper oxide

Recycling Fe elements from copper slag is beneficial to decrease the pressure on Chinese dependence on imported iron ore for the content of iron element in copper slag is as high as 30 %~40 %. The feasibility of copper chlorination was analyzed by performing thermogravimetric analysis on the chlorination process of CuO-FeCl₂ system at temperatures of 823 K, 873 K, 923 K and 973 K respectively. The influences of temperature and flow rate of argon gas in CuO-FeCl₂ system on the reaction were discussed. The results show that chlorination rate increases with rising temperature. At the condition of 50 mL/min of argon flow rate, chlorination rate reaches a maximum of 62.46 % in CuO-FeCl₂ system. The chlorination reaction of the system is determined to be zero order reaction by deriving kinetic equation of chlorination, and the system transited from chlorination kinetic region to diffusion region at 873 K. The reaction rate in kinetic region depends on CuCl₂ evaporation rate, and the reaction rate of diffusion region depends on the rate of surface diffusion from FeCl₂ to CuO.