(298e) Carbon Dioxide Capture Performance Characterization of Mesoporous Carbon Impregnated with Triethylenetetramine

The increasing world population, followed by increasing energy consumption, leads to unprecedented elevating concentrations of carbon dioxide in the atmosphere. Carbon Dioxide Capture, Utilization, and Storage (CCUS) technology has great potential to reduce the impact of increasing carbon dioxide emissions, which is causing climate change. Conventional carbon capture method of absorption by amine solvent poses several limitations, such as high energy consumption for regeneration, corrosion to the equipment, and environmental issues. Meanwhile, adsorption by solid adsorbents is a more environmentally friendly technology and represents a low-energy consumption process. Among carbon dioxide adsorbents, porous carbon material emerged as one of the most versatile adsorbent materials due to its high surface area and selectivity, as well as ease of surface modification and handling. Amine functionalization of porous carbon material also provides advantages such as reduced corrosion problems and energy consumption for regeneration.

In this research, mesoporous carbon (MC) was impregnated with Triethylenetetramine (TETA) to increase the adsorption ability and selectivity towards carbon dioxide. Mesoporous carbon is chosen as it has a larger surface area to accommodate a large number of amines compared to commercial activated carbon, which mainly consists of micropores. The as-synthesized MC was characterized. MC was impregnated with TETA concentrations of 10%, 20%, 30%, 40%, and 50%, and the resulting material was characterized. The presence of nitrogen element (N) in MC-TETA was observed, which indicates that MC-TETA was successfully modified with TETA. The total surface area of MC was decreased after amine-impregnation with TETA. Furthermore, it was found that the material was stable at 100-125°C, indicating that amine decomposition did not occur at this point. This data is pivotal in determining the desorption temperature without causing amine degradation.

The carbon dioxide capture performance of mesoporous carbon impregnated with TETA (MC-TETA) was evaluated by comparing it with commercially available activated carbon and zeolite, which were also impregnated with TETA. Based on the CO₂ adsorption performance results, it can be understood that the appropriate TETA helped to improve the adsorption ability compared to the unmodified MC. Meanwhile, amine impregnation of activated carbon (AC-TETA) and zeolite (Zeo-TETA) reduced the adsorption ability compared to its unmodified form. Therefore, it can be concluded that MC-TETA is the most suitable material for amine impregnation due to its large pore size, which is attributed to better accommodating large numbers of amines.