Pure ammonia direct decomposition using rod-electrode-type microwave plasma source

Abstract

This paper presents the experimental results of ammonia (NH3) decomposition without catalyst and dilution using a rod-electrode-type microwave plasma source (MPS) at atmospheric pressure. The direct decomposition ratio of pure NH3 was investigated in relation to the flow rate into the rod-electrode-type MPS and the average transmission power to the rod-electrode-type MPS. The decomposition ratio increased with decreasing the flow rate and with increasing the average transmission power. For example, the decomposition ratio was demonstrated to exceed 40 % at the flow rate of 0.2–0.8 L/min and the average transmission power of about 63–166 W. The highest decomposition ratio was approximately 84 % at the flow rate of 0.2 L/min and the average transmission power of approximately 112 W, and the hydrogen yield was approximately 90 %.