title: Carbamate stabilities of sterically hindered amines from quantum chemical methods: relevance for CO2 capture.
abstract: The influence of electronic and steric effects on the stabilities of carbamates formed from the reaction of CO2 with a wide range of alkanolamines was investigated by quantum chemical methods. For the calculations, B3LYP, M11-L, MP2, and spin-component-scaled MP2 (SCS-MP2) methods were used, coupled with SMD and SM8 solvation models. A reduction in carbamate stability leads to an increased CO2 absorption capacity of the amine and a reduction of the energy required for solvent regeneration. Important factors for the reduction of the carbamate stability were an increase in steric hindrance around the nitrogen atom, charge on the N atom and intramolecular hydrogen bond strength. The present study indicates that secondary ethanolamines with sterically hindering groups near the N atom show significant potential as candidates for industrial CO2-capture solvents.
authors.affiliation: Laboratory of Organic Chemistry, Wageningen University, Dreijenplein 8, 6703 HB Wageningen (The Netherlands), Tel: (+31) 317-482361.
authors.forename: Satesh
authors.initials: S
authors.lastname: Gangarapu
authors.forename: Antonius T M
authors.initials: AT
authors.lastname: Marcelis
authors.forename: Han
authors.initials: H
authors.lastname: Zuilhof
keywords: CO2 capture; alkanolamines; carbamate stability; computational chemistry; cyclic amines