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

Abstract

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 °C, activated carbon had the highest NO and SO2 adsorption capacity (120.83 and 3549.61 μg/g, respectively). At 110 °C, the highest NO and SO2 adsorption capacity (6.20 and 1182.46 μg/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.

Sorption of Polar Sorbates NH3, H2O, SO2 and CO2 on Selected Inorganic Materials

“…In the case of SO 2 adsorption, the dominant interaction is the formation of hydrogen bonds with functional groups present on the surface. The work of Verner et al [ 51 ] demonstrated a high affinity of SO 2 for the surface of various adsorbents (activated carbon, bentonite, and silica gel) which was interpreted by both the porosity and the chemical nature of the surface of these materials.…”

Nitrogen-Doped Carbon Cryogels as Adsorbents: Efficient Removal of Organophosphate Pesticides from Water and Assessment of Toxicity Reduction

“…The adsorption-based processes are generally determined by the adsorbent's surface chemical composition and textural properties [44,45]. Due to their very favorable properties, carbonaceous materials are especially attractive for the adsorption of both organic and inorganic solutes from the aqueous phase.…”