Measurements of Microwave Argon-Hydrogen Plasma Jet Temperature and Its Temperature during Propane Decomposition

Abstract

In order to obtain information on the decomposition of hydrocarbons in a microwave plasma jet, the temperature of the microwave argon-hydrogen plasma jet and its temperature during propane decomposition were measured using the thermocouple and the spectroscopic method. Under the condition of, the argon flow rate of 19.1 l/min, the hydrogen flow rate of 0.63 l/min and the output of 470 W, the mean temperature which was measured by the thermocouple reached 15800K at the center of the plasma jet. lt was dependent on the output and the argon-hydrogen mixing ratio but scarcely on the operating gas flow rate. During propane decomposition, it dropped to lower than 13000K under the conditions used. The excitation temperature of ArI was above 10000K, which was much higher than the gas temperature, suggesting that the microwave argon-hydrogen plasma jet is not in thermal equilibrium. The products distribution in the decomposition of propane in the microwave plasma jet was compared with that in the thermal decomposition of propane and the decomposition scheme in the former was proposed.