Study of ammonia decomposition after injection into an induction plasma

The thermal decomposition of NH3, following its introduction into an induction plasma operating at reduced pressure, is investigated. Thermodynamics are initially used to predict the decomposition products of the ammonia and to determine the minimum temperature required for complete decomposition. Experimentally, a cold wall reactor is used to contain the plasma, into which ammonia is injected both axially and radially. The temperature profiles for the plasma stream are evaluated by means of an enthalpy probe while the composition profiles of the plasma gas are measured in the mixing zone with the aid of the same enthalpy probe but now connected to a quadrupole mass spectrometer. The results show that ammonia decomposition is strongly affected by both mass and energy transfer limitations. Furthermore, the results show that both radial and axial injection each have their drawbacks and advantages.