The chlorination behaviors of two chalcopyrite concentrates and their pure constituents in Cl^sub 2^ + N^sub 2^ were investigated by thermogravimetric analysis (TGA) in nonisothermal conditions up to 1000 deg C. The effect of temperature on the reaction of chlorine with both concentrates was studied between 170 deg C and 300 deg C under isothermal conditions. The effects of gas flow rate, chlorine content of the gas mixture, and reaction time on the reaction rate were also investigated. The reaction products were analyzed by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Results showed that the kinetics of chlorination of chalcopyrite concentrates generating chlorides of Cu, Pb, Zn, Fe, and S was rapid at about 300 deg C. The iron and sulfur chlorides were volatilized, leading to a residue containing valuable metal chlorides.