Adsorption performance of MCM-41 impregnated with amine for CO2 removal

Carbon dioxide (CO2) removal is increasingly important because a high CO2 concentration in the atmosphere leads to global climate changes. In addition, the removal of CO2 is also required in cryogenic plants to prevent CO2 solidification. The removal can be achieved by using methods such as liquid absorption, solid adsorption cryogenic techniques, and selective diffusion through polymer, ceramic, or metallic membranes. At present, chemical absorption using liquid amine has been commercially used in large-scale separation. However, a relatively high heat of absorption caused the high cost of regenerating primary and secondary amines. In addition, solvent leakage and corrosion are also a problem. Alternatively, studies have been carried out to investigate the potential use of adsorption process that requires less energy, is cost effective and is easy to handle in a wide range of temperatures and pressures. This paper discusses carbon dioxide adsorption on solid adsorbent in pressure swing adsorption (PSA) system and its regeneration performance. The adsorbent used is MCM-41 and is modified using MEA and DEA to enhance the adsorption of CO2. In this study, it was found that modified MCM-41 using 25 wt.% MEA has high carbon dioxide removal even after the 10 cycles of operation.

► MCM-41 was modified using amines to enhance CO2 removal.
► MEA and DEA reduce the surface area, but increase the percentage of CO2 removal.
► At 25 wt.% MEA-MCM-41, the purity of the exit gas is 99.91 %.