Nitrogen fixation as NOx using air plasma coupled with heterogeneous catalysis at atmospheric pressure

• Published in: Plasma processes and polymers 2024-01, Vol.21 (1), p.n/a
• Main Authors: Pei, Xuekai, Li, Yiheng, Luo, Yi, Man, Chenxi, Zhang, Yumin, Lu, Xinpei, Graves, David B.
• Format: Article
• Language: English
• Subjects: Air plasma; Aluminum oxide; Atmospheric pressure; atmospheric pressure air plasma; Catalysis; Catalysts; Direct current; energy cost; Energy costs; floating catalyst; Gas flow; Glow discharges; nitrogen fixation; Nitrogenation; NOx production; Plasma jets
• ISSN: 1612-8850; 1612-8869
• DOI: 10.1002/ppap.202300135

This study presents insights into the use of activated Al2O3 ${\text{Al}}_{2}{{\rm{O}}}_{3}$ catalysts to improve the energy efficiency of NOx ${\text{NO}}_{x}$ production in atmospheric pressure air plasma. The introduction of catalysts in the direct current glow discharge system reduces the energy cost of NOx ${\text{NO}}_{x}$ production by up to 45% at low gas flow rates. Notably, even when positioned away from the plasma zone, the catalyst enhanced NOx ${\text{NO}}_{x}$ production, suggesting a significant role for the catalytic activation of downstream neutral species. The study also introduced a novel approach involving an air plasma jet infused with floating catalyst powder. This method significantly increased energy efficiency at higher discharge currents, with an associated energy cost of 2.9 MJ/mol for NOx ${\text{NO}}_{x}$ production. This study revealed an innovative, energy‐efficient method for NOx production, utilizing an air plasma jet with a floating catalyst, achieving a record‐low energy cost of 2.9 MJ/mol.