Abstract:High temperature treatment method is the main research direction in treating spent cathode of aluminum electrolysis. The effects of calcination temperature, calcination time and particle size of sample on removal efficiency of cyanide, fluoride and other elements were studied, and the relationship between degree of graphitization, true density, powder resistivity and calcination temperature were investigated. The results show that cyanide can be completely decomposed by roasting at 600 ℃, fluorine and other components (without carbon) can be removed by roasting at 1 000 ℃ above. The removal rate of fluorine and other components rises with the increase of calcination temperature. The graphitization degree and true density of graphite fragments rises with the increase of calcination temperature. When the calcination temperature reaches 2 600 ℃, the graphitization degree and true density of graphite fragments reach 98.4% and 2.270 3 g/cm3 respectively. The resistivity of graphite powder drops with the increase of calcination temperature. The calcinated graphite grains are of high application value.