Experimental Study on Adsorption of SO2 and NH3 by Activated Carbon with Monometallic Active Sites at Low Concentration under Room Temperature.

SO2 and NH3 are toxic compounds and are the main sources of airborne molecular contaminants (AMCs). Even at low concentrations, they can cause equipment corrosion and reduce product yield. Therefore, it is crucial to develop a combined SO2 and NH3 capture material with a simple process and a high adsorption capacity. In this study, dynamic adsorption breakthrough experiments were conducted at 23 °C under an air pollutant concentration of 90 ppm. The synergistic adsorption results showed that Cu/AC-0.05 had a high adsorption capacity of 1.03 mmol of SO2/g and 1.45 mmol of NH3/g. Furthermore, to confirm the rationality of the modification method, characterization methods such as BET, SEM-EDX, XRD, and TG-DSC were used to study the new adsorbent and spent adsorbent. The results showed that copper was successfully attached to the activated carbon and distributed uniformly. In this study, efficient coremoval performance of SO2 and NH3 was achieved by modifying single metal active sites. Through a comprehensive analysis of the characterization results, the surface reaction mechanism of SO2 and NH3 on the prepared material was further determined. This work provides a feasible option for a highly efficient adsorbent for both SO2 and NH3 capture at low concentrations under room temperature.