ACS Appl Mater Interfaces. 2015 Aug 19;7(32):17603-13. doi: 10.1021/acsami.5b04153. Epub 2015 Aug 05.

Transport Properties of Amine/Carbon Dioxide Reactive Mixtures and Implications to Carbon Capture Technologies.

ACS applied materials & interfaces

Salomon Turgman-Cohen, Emmanuel P Giannelis, Fernando A Escobedo

PMID: 26200117 DOI: 10.1021/acsami.5b04153

Abstract

The structure and transport properties of physisorbed and chemisorbed CO2 in model polyamine liquids (hexamethylenediamine and diethylenetriamine) are studied via molecular dynamics simulations. Such systems are relevant to CO2 absorption processes where nonaqueous amines are used as absorbents (e.g., when impregnated or grafted onto mesoporous media or misted in the gas phase). It is shown that accounting for the ionic speciation resulting from CO2 chemisorption enabled us to capture the qualitative changes in extent of absorption and fluidity with time that are observed in thermogravimetric experiments. Simulations reveal that high enough concentration of reacted CO2 leads to strong intermolecular ionic interactions and the arrest of molecular translations. The transport properties obtained from the simulations of the ionic speciated mixtures are also used to construct an approximate continuum-level model for the CO2 absorption process that mimics thermogravimetric experiments.

Keywords: capture; carbon dioxide; molecular dynamics; multiscale; polyamines; sequestration

Publication Types

• Journal Article
• Research Support, Non-U.S. Gov't