Sulfur oxides (SO2) and nitrogen oxides (NOx) are principal pollutants in the atmosphere due to their harmful impact on human health and environment. We use molecular simulations to study different adsorbents to remove SO2 and NOx from flue gases. Twelve representative porous materials were selected as possible candidates, including metal-organic frameworks, zeolitic imidazolate frameworks, and all-silica zeolites. Grand canonical Monte Carlo simulations were performed to predict the (mixture) adsorption isotherms to evaluate these selected materials. Both Cu-BTC and MIL-47 were identified to perform best for the removal of SO2 from the flue gases mixture. For the removal of NOx, Cu-BTC was shown to be the best adsorbent. Additionally, concerning the simultaneous removal of SO2, NOx, and CO2, Mg-MOF-74 gave the best performance. The results and insights obtained may be helpful to the adsorbents selection in the separation of SO2 and NOx and carbon capture. (c) 2014 American Institute of Chemical Engineers AIChE J, 60: 2314-2323, 2014