METHOD FOR PRODUCING TETRAFLUOROETHYLENE AND CHLOROTRIFLUOROETHYLENE

PROBLEM TO BE SOLVED: To provide a method for producing tetrafluoroethylene and a chlorotrifluoroethylene stably and at high yield even in a large scale.SOLUTION: The method for producing tetrafluoroethylene and chlorotrifluoroethylene is characterized by heating a raw material gas including, as main components, flon 21 (CHClF) and flon 22 (CHClF) by bringing into contact with steam to cause reactions having the following steps (a) to (c), wherein (a) a raw material gas supplying step of supplying the raw material gas including the flon 21 and the flon 22 with molar ratios of the flon 21 to the flon 22 of 2/98 through 80/20 and heating over a clouding point and 400°C or lower, (b) a steam supplying step of supplying steam with elevated temperatures at 800°C through 1,100°C and (c) a reaction step of heating the raw material gas by bringing into contact with the steam to cause reaction to give the tetrafluoroethylene and the chlorotrifluoroethylene, where the molar ratio of the contact amounts of the raw material gas to the steam be 30/70 through 2/98.