Kinetics of Carbon Dioxide Binding by Promoted Organic Liquids

The reaction kinetics of carbon dioxide and CO2-binding organic liquids (CO(2)BOLs) promoted by piperazine (PZ) and its derivatives were investigated experimentally by stopped-flow conductimetry. The study was carried out at 298 K and for a concentration range of 0-0.25 kmol m(-3) of PZ, 1-(2-aminoethyl)piperazine (AEPZ) or 1-(2-hydroxyethyl)piperazine (NHEPZ) while the superbase (1,1,3,3-tetramethylguanidine or 1,8-diazabicyclo[5.4.0]undec-7-ene) concentrations were kept constant at 10.0 wt %. Based on pseudo-first-order reaction conditions, the intrinsic reaction rate data were analyzed according to a modified termolecular reaction mechanism. The results showed that the rate of reaction between CO(2)BOLs and CO2 could be significantly enhanced by blending with small amounts of PZ, NHEPZ or AEPZ as promoters.