Reduction of energy requirement of CO2 desorption from a rich CO2-loaded MEA solution by using solid acid catalysts

In this work, the regeneration of rich CO 2 -loaded monoethanolamine (MEA) solvent with two catalysts (e.g. SAPO-34 and SO 4 2− /TiO 2 ) was investigated in order to reduce the energy requirement for solvent regeneration. The regeneration behavior with and without catalyst of a 5M MEA solution with an initial CO 2 loading of 0.5   mol   CO 2 /mol amine at 96   °C was studied to compare their CO 2 desorption rate and heat duties. The results show that the two solid acid catalysts can reduce the heat duty for solvent regeneration and increase the CO 2 desorption rate in comparison with blank test. The mechanism of CO 2 desorption with catalyst in 5M MEA was proposed based on the result of catalyst characterization (e.g. N 2 absorption/desorption experiment, Py-IR, NH 3 -TPD, FT-IR and XRD) to better understand the desorption process. The results indicate that SAPO-34 with the higher joint value of Brϕnsted/Lewis acid sites ratio (B/L) and mesopore surface area (MSA) shows the faster CO 2 desorption rate and lower heat duty than SO 4 2− /TiO 2 . Based on the experimental results, the addition of solid acid catalysts into amine solution could be considered as one of choices to reduce the heat duty for CO 2 desorption from CO 2 -loaded amine solvent.