Effects of Structure and Composition of Adsorbents on Competitive Adsorption of Gaseous Emissions: Experiment and Modeling

Dangerous gases arising from combustion processes must be removed from the air simply and cheaply, e.g., by adsorption. This work is focused on competitive adsorption experiments and force field-based molecular modeling of the interactions at the molecular level. Emission gas, containing CO, NO, SO2, and CO2, was adsorbed on activated carbon, clay mineral, silicon dioxide, cellulose, or polypropylene at two different temperatures. At 20 degrees C, activated carbon had the highest NO and SO2 adsorption capacity (120.83 and 3549.61 mu g/g, respectively). At 110 degrees C, the highest NO and SO2 adsorption capacity (6.20 and 1182.46 mu g/g, respectively) was observed for clay. CO was adsorbed very weakly, CO2 not at all. SO2 was adsorbed better than NO, which correlated with modeling results showing positive influence of carboxyl and hydroxyl functional groups on the adsorption. In addition to the wide range of adsorbents, the main novelty of this study is the modeling strategy enabling the simulation of surfaces with pores of controllable sizes and shapes, and the agreement of the results achieved by this strategy with the results obtained by more computationally demanding methods. Moreover, the agreement with experimental data shows the modeling strategy to be a valuable tool for further adsorption studies.

Automated summary

This study focuses on competitive adsorption experiments and force field-based molecular modeling of interactions. It was found that activated carbon had the highest adsorption capacity for NO and SO2 at 20 degrees C, while clay had the highest adsorption capacity at 110 degrees C. The modeling results showed that carboxyl and hydroxyl functional groups had a positive influence on adsorption. The novelty of this study lies in the modeling strategy that allows simulation of surfaces with controlled pore sizes and shapes.