Continuous N2O Capture and Reduction to N2 Using Ca-Zeolite Adsorbent and Pd/La/Al2O3 Reduction Catalyst

There is an urgent need to develop effective methods for converting nitrous oxide (N2O) into nonharmful N-2 because N2O is a potent greenhouse gas, and its increasing concentration in the atmosphere is a major concern for global warming. In this study, we developed a two-step N2O capture and reduction system, employing CaO-incorporated zeolites (Ca-zeolites) as N2O adsorbents and Pd nanoparticles on La-containing Al2O3 (Pd/La/Al2O3) as catalysts for N2O reduction. This process is suitable for continuous operation over a temperature swing of 50-150 degrees C. The N2O capture capacity and subsequent reduction ability were preserved for at least 15 h (10 cycles). Notably, this system can operate at low temperatures (below 150 degrees C) using a simple temperature-swing process in the presence of O-2.