Adsorption is a potential technology that is expected to meet NOx ultra-low emission standards and achieve the recovery of NO2. In this study, the adsorption/desorption behavior of NOx with competitive gases (e.g., H2O(g) and CO2) was studied on MFI zeolites with different Si/Al ratios and under different relative humidity (0~90% RH). Sample characterization of self-synthesizing zeolites was conducted by means of X-ray diffraction, Ar adsorption-desorption, and field emission scanning electron microscopy. The results showed that low-silica HZSM-5(35) showed the highest NOx adsorption capacity of 297.8 μmol/g (RH = 0) and 35.4 μmol/g (RH = 90%) compared to that of other adsorbents, and the efficiency loss factor of NOx adsorption capacity at 90%RH ranged from 85.3% to 88.1%. A water-resistance strategy was proposed for NOx multicomponent competitive adsorption combined with dynamic breakthrough tests and static water vapor adsorption. The presence of 14% O2 and lower adsorption temperature (25 °C) favored NOx adsorption, while higher CO2 concentrations (~10.5%) had less effect. The roll-up factor (η) was positively correlated with lower Si/Al ratios and higher H2O(g) concentrations. Unlike Silicalite-1, HZSM-5(35) exhibited an acceptable industrial desorption temperature window of NO2 (255~265 °C). This paper aims to provide a theoretical guideline for the rational selection of NOx adsorbents for practical applications.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.