Atmospheric carbon dioxide levels reaching ~ 417 ppm and the associated alarming effects of global warming call for advancements in carbon dioxide capture and utilization technologies [1]. Post-combustion CO2 capture at the emission source itself is actively researched as a possible solution. Biomass (coco peat and chitosan) derived carbons are considered the best environment friendly materials for CO2 capture by adsorption at ambient temperatures [2]. The CO2 adsorption capacity of carbon materials depends on their structural properties and chemical nature of the functionalization of carbon networks. For this purpose, amorphous carbon materials derived from coco peat by KOH activation and melamine as pore-directing template have been studied for CO2 adsorption capacity [3]. It is found that coco peat-derived carbons could achieve a maximum CO2 adsorption capacity of 4.8 mmol g-1 at 298 K and 1 bar. The pore size distribution and pore volume of biomass derived carbons can be tuned to achieve CO2 capture effectively at room temperature. The other materials of interest are layered double hydroxides (LDHs) which can capture CO2 at around 200 C [4]. The material chosen for this study is SrMgAl LDH which shows higher thermal stability and ability for CO2 capture at 200 °C. The active species in this material seems to be MgO sites that are generated upon calcination. This material can be activated effectively at 600 °C for CO2 capture. The background literature and the results obtained on biomass derived carbons and LDH materials will be discussed.

References:

[1] S. Choi, J.H. Drese, C.W. Jones, ChemSusChem, 2009, 2, 796; ACS Omega 2023, 8, 11643.
[2] X. Yuan et. al. Renewable Sustainable Energy Rev, 2022, 162, 112413.
[3] S.M. Varghese, A.R. Chowdhury, D.N. Arnepalli, G. Ranga Rao, Carbon Trends, 2023, 10, 100250.
[4] Y. Gao et. al. J. Mater. Chem. A, 2013, 1, 12782.