The employment of amino acids as green fast-reacting biodegradable solvents for CO2 capture has been recently considered a viable option owing to their elevated solubility for CO2. However, in the application of L-lysine as an absorbent for CO2 capture, there is no comprehensive understanding of the continuous mass transfer process in gas-liquid contactors, which leads to the lack of guidance for the industrial flue gas decarbonization processes. To enhance the mass transfer of CO2 capture utilizing incorporated alkanolamine solutions along with elucidate the impact of amino-acid incorporation, the capability of a novel multi-component absorbent, including methyldiethanolamine (MDEA), diisopropanolamine (DIPA), and L-lysine (Lys) was assessed for the first time in a tree-shaped parallel micro-contactor. The CO2 capture percent, total volumetric gas-phase mass transfer coefficient (TGMTC), and CO2 molar flux (NAaV) were explored over an entire range of feed gas flow rate (60–240 mL/min), mixed absorbent flow rate (3–9 mL/min), CO2 concentration in the feed (5–15 vol%), and absorption temperature (25–45 ˚C). Under a given temperature of 40˚C, the TGMTC value attained its peak at 47.52 kmol/m3.h.kPa with a concentration of MDEA-DIPA-Lys (30-3-7) wt% under a Qg= 240 mL/min, and Ql=9 mL/min. Besides, in comparison to the aqueous pure solution of MDEA, the values of the NAaV and TGMTC for the ternary MDEA-DIPA-Lys solution has been enhanced by 3.21 and 3.34 times, respectively. This illustrates the possible benefit of green L-lysine amino acid within the MDEA-DIPA mixture concerning the CO2 absorption process.
