N Atom Radicals and N₂(A³∑_u⁺) Found To Be Responsible for Nitrogen Oxides Conversion in Nonthermal Nitrogen Plasma

Abstract

All species that are likely to be responsible for nitrogen oxides (N 2 O, NO, and NO 2 ) conversion in nitrogen plasma are analyzed in detail through carefully designed systematic experiments and theoretical analysis. The effect of ppm-level CO 2 , CO, and 1% CO on N 2 O conversion reveals that the N 2 O conversion occurs mainly by interaction with N 2 (A 3 ∑ u + ) excited species. The effect of 1% CO on the NO conversion suggests that only N atom radicals are predominantly involved in NO conversion. NO 2 conversion, on the other hand, occurs by interaction with both N 2 (A 3 ∑ u + ) and N atom radicals. Therefore, only two active species, N 2 (A 3 ∑ u + ) and N atom radicals, are found to be responsible for nitrogen oxides conversion in nitrogen plasma.

Effect of reactor configuration on nitric oxide conversion in nitrogen plasma

“…For these experiments, the energy per pulse was about 0.192 J. As found previously,11 NO 2 and N 2 O are formed as byproducts when NO is converted in N 2 . Therefore, total NO x conversion was calculated, rather than NO conversion, because total NO x conversion reflects the degree of direct decomposition of NO into N 2 and O 2 .…”

“…The model parameters α and β for electron‐impact reactions were determined from experimental data using an optimization method 12. On the basis of the prior work,11, 12 a total of 20 reactions with two electron collision reactions, shown in Table 2, were selected to simulate the system of NO in N 2 .…”

High-performance gas sensors with temperature measurement

“…The gases with first ionization energies higher than 10.3 eV are harder to ionize than nitrogen31, but they affect energy and charge transformation33 during gas discharge in a mixture with N 2 . Since the first ionization energies of the gases probed are greater than 10.3 eV, the ionization process will depend mainly on the ionization of N 2 from its two metastable states, and with lower excitation energies3334353637 of ∼6.2 and ∼8.4 eV, respectively. The first ionization coefficient32 of N 2 , α , reflects ionization ability of gas from collision with electrons, and is determined by the applied electric field E and the partial pressure P of N 2 (Supplementary Fig.…”

Methane conversion in pulsed corona discharge reactors

“…Mechanical, bimetallic thermometers placed in the reactor outlet stream proved to be relatively unresponsive and displayed near ambient temperatures, despite the fact that the reactor external support casing (a 0.05 m diameter stainless steel tube concentric to the reactor cathode) was hot to the touch (>350 K) near the reactor outlet. Therefore, the hydrogen switch based reactor (used for NO x conversion in our previous work [22,25,28,[32][33][34][35][36][37]) with the same reactor geometry as the thyratron-based reactor (tube length, 0.914 m; tube diameter, 0.024 m; wire diameter, 1 mm) was used during methane conversion to estimate the temperatures in the thyratron-based reactor. Fig.…”