The urgent need to address the current climate crisis
has led to
concerted efforts to develop low-cost and sustainable methods to remove
carbon dioxide from the atmosphere. Carbon capture and storage (CCS)
and negative emissions technologies (NET’s) offer the most
promising paths forward to offsetting global emissions. In this study,
we explore the potential of kraft lignin, a readily available biomaterial,
as a low-cost alternative for the development of a CO2 sorbent.
The approach leverages the known ability of amines to reacting with
carbon dioxide and forming a stable compound. Commercially available
kraft lignin was modified with diethylenetriamine (DETA), triethylenetetramine
(TETA), and tetraethylenepentamine (TEPA) using a one-pot synthesis
approach via the Mannich reaction. The sorbent was evaluated for porosity,
accessible amine density, and nitrogen content. The CO2 capture experiments revealed that the resulting sorbent can capture
0.80 (±0.03) mmol of CO2 per gram of sorbent.