Rates of formation of ethylene, hydrogen, and methane have been measured at 630 °C for the thermal decomposition of ethane at pressures between 100 and 620 Torr, with various pressures (approximately 1 to 100 Torr) of added hydrogen sulfide. The effect of the H2S was to increase the rate of methane formation and to decrease the rate of ethylene and hydrogen formation. Rates of formation of all three of these gases decreased with increasing hydrogen sulfide pressures. The quantitative data obtained and the partial product analysis indicate that a complex mechanism is operative. Possible qualitative explanations for the observations are discussed.
