In this study, to appraise the performance of hybrid Diethanolamine-methanol solvent for the CO2 absorption process in the packed bed, the volumetric overall gas phase mass transfer coefficient (KGaV) and the absorption percentage (η) under different operating conditions were investigated including inlet solvent temperature 25–65 °C, reboiler temperature 75–115 °C, the inlet CO2 concentration 5–15 vol%, solvent flow rate 0.50–1.50 lit/min, gas flow rate 50–100 lit/min and solvent concentration 10–30 wt%. The results show that by reducing the reboiler temperature from 115 to 95 °C, the mass transfer coefficient reduces 1%, but the reboiler temperature reduces 17% instead. This issue has a great effect on energy saving in the desorption section. Moreover, by adjusting the operating condition, the maximum KGaV and η were 4.69 (kmol m−3 h−1. kPa−1) and 99.9%, respectively. The results of this study indicate that the use of DEA-methanol solution had equal and even higher absorption percentage (up to 99.9%) than the conventional MEA aqueous solution in addition to the lower regeneration temperature.
