Considering the slow reaction kinetics of tertiary alkanolamines with carbon dioxide, in this study, ammonia additive (NH3) has been used as a rate promoter for CO2 absorption by triethanolamine (TEA) solvent. The experiments were performed in a T-shaped microchannel with a circular cross-section. Effect of five independent variables including: temperature (20-40 ℃), ammonia concentration (0-5 wt.%), triethanolamine concentration (10-30 wt.%), gas flow rate (150-250 ml/min) and liquid flow rate (2-6 ml/min) on CO2 absorption efficiency (η) was investigated. The results showed that in the ammonia concentration range of 0-4 wt.%, adding ammonia to TEA leads to an increase in CO2 absorption efficiency from 33.91% to 93.52%, but in higher concentrations (4-5 wt.%), the adding ammonia is accompanied by a decrease in CO2 absorption efficiency.
