Promoted alkanolamine solutions with amino acid L-arginine for post-combustion CO2 capture in a micro-reactor

With the aim of replacing amine solvents, in the current study, the novel mixture solutions were proposed for CO2 absorption combining amino acid (L-Arginine) with primary, secondary, and tertiary alkanolamines. The mass transfer performance of CO2 capture in the aqueous solutions of MEA-ARG, DEA-ARG, and MDEA-ARG was intensified under operational conditions of 4-12 wt% arginine concentration, 120-300 mL/min feed solvent flow rate, 3-9 mL/min inlet gas flow rate. In this regard, a T-shape micro-reactor with a diameter of 800 mu and a length of 29.5 cm was utilized. All the experiments were performed under the atmospheric pressure and absorption temperature of 45 ?. Considering industrial restrictions, the total concentration of mixtures was kept constant at 25 wt% for MEA-ARG, 35 wt% for DEA-ARG, and 50 wt% for MDEA-ARG. The results of CO2 absorption efficiency (e(f)), overall volumetric mass transfer coefficient, OVGMTC, (K(G)a(V)), and volumetric mass transfer flux (N(A)a(V)) indicated that in all three cases, the aqueous MEA-ARG solution has the highest value of 96%, 90.95 kmol/m(3).h.kPa, and 361.82 kmol/h.m(3), respectively. Also, while the gas and liquid flow rates were kept constant in their middle points, adding arginine from 4 to 12 wt% enhanced the values of the e(f) from 92.55% to 93.76% for DEA-ARG and from 79.20% to 93.23% for MDEA-ARG solutions, respectively. However, the results were obtained differently for solution MEA-ARG.