Kinetics of CO2 capture by carbon dioxide binding organic liquids: Experimental and molecular modelling studies

Abstract

In the scope of this work, new carbon dioxide binding organic liquids (CO2BOLs) were developed and kinetic parameters in terms of pseudo first-order rate constants for homogenous reaction between CO2 and CO2BOLs in 1-hexanol were obtained by using stopped-flow method with conductivity detection. As an amidine DBN (1,5-diazabicyclo[4.3.0]non-5-ene) and as a guanidine TBD (1,5,7-triazabicyclo[4.4.0]dec-5-ene) and BTMG (2-tert-butyl-1,1,3,3-tetramethylguanidine) were investigated. Experiments were performed by varying organic base (amidine or guanidine) weight percentage in 1-hexanol medium for a temperature range of 288–308K. A modified termolecular reaction mechanism was used to analyse the experimental kinetic data. In addition, quantum chemical calculations by using B3LYP, MP2 and CCSD methods were performed to reveal the structural and energetic details of the single step termolecular reaction mechanism. Experimental and theoretical activation energies for these novel carbon dioxide capturing organic liquids were also unveiled.