The reaction rates of CO 2 with an innovative CO 2 -capturing organic solvent (CO 2 COS), consisting of blends of 2-tert-butyl-1,1,3,3-tetramethylguanidine (BTMG) and 1-propanol, were obtained as function of BTMG concentration and temperature. A stopped-flow apparatus with conductivity detection was used. The reaction was modeled by means of a modified termolecular reaction mechanism which resulted in a second-order rate constant, and activation energies were calculated for a defined temperature range. Quantum chemical calculations at the B3LYP/6-31G(d) level also produced the activation energy of this reaction system which strongly supports the experimental findings.

The reaction kinetics of CO 2 absorption into new carbon dioxide binding organic liquids (CO 2 BOLs) was comprehensively studied to evaluate their potential for CO 2 removal. A stopped-flow apparatus with conductivity detection was used to determine the CO 2 absorption kinetics of novel CO 2 BOLs composed of DBN (1,.0]non-5ene)/1-propanol and TBD (1,5,7-triazabicyclo[4.4.0]dec-5-ene)/1-butanol. A modified termolecular reaction mechanism for the reaction of CO 2 with CO 2 BOLs was used to calculate the observed pseudo-first-order rate constant k 0 (s −1 ) and second-order reaction rate constant k 2 (m 3 /kmol.s). Experiments were performed by varying organic base (DBN or TBD) weight percentage in alcohol medium for a temperature range of 288-308 K. It was found that k 0 increased with increasing amine concentration and temperature. By comparing using two different CO 2 BOL systems, it was observed that the TBD/1-butanol system has faster reaction kinetics than the DBN/1-propanol system. Finally, experimental and theoretical activation energies of these CO 2 BOL systems were obtained and compared. Quantum chemical calculations using spin restricted B3LYP and MP2 methods were utilized to reveal the structural and energetic details of the single-step termolecular reaction mechanism.

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