Fig. 2: The reaction mechanism for CO₂ captured in TREA solution and CO₂ absorption performance in 3 M TREA solvent.

a A representation of the proposed CO₂ capture process is shown, where the TREA solution captures CO₂ by stabilizing the bicarbonate on an equimolar basis. b A schematic figure of the CO₂ absorption column used for the capture experiments. The column is 3 meters in height with a diameter of 3 inches. c CO₂ absorption experiment results with varying TREA flow rates at fixed gas flow rate (0.8 m³ h⁻¹) and CO₂ concentration in gas flow (3% CO₂). d Effect of L/CO₂ ratios on CO₂ absorption capacity at various values of TREA flow rates (2–5 L h⁻¹), gas flow rates (0.5–0.8 m³ h⁻¹), and CO₂ concentrations (3–5%). CO₂ absorption capacity shows a linear correlation with L/CO₂ ratio, regardless of TREA flow rate, gas flow rate, and CO₂ concentration.