CO2 absorption into an ionic liquid
This is a brief movie showing CO2 diffusing into the ionic liquid 1-n-hexyl-3-methylimidazolium bis(trifluoromethanesulfonyl)amide. Marcos Perez-Blanco performed the simulations and Kristina Firse helped with the visualization. Read more about this work in Marcos Perez-Blanco and Edward J. Maginn, “Molecular Dynamics Simulations of Carbon Dioxide and Water at an Ionic Liquid Interface”, Journal of Physical Chemistry B, 2011, 115, 10488-10499 and Marcos Perez-Blanco and Edward J. Maginn, “Molecular Dynamics Simulations of CO2 at an Ionic Liquid Interface: Adsorption, Ordering and Interfacial Crossing”, Journal of Physical Chemistry B (cover article), 2010, 36, 11827.
(If the movie does not load in your browser, you can access it by clicking this link. You will need a Box account.)
Funding provided by the Department of Energy (DE-FC26-07NT43091) and (DE-AR0000119).
Computing shear viscosity with nonequilibrium molecular dynamics
This movie shows how one can compute the shear viscosity of a fluid using the reverse nonequilibrium molecular dynamics method. In this movie, the viscosity of an ionic liquid is computed by Marcos Perez-Blanco. Read more about these methods in the following papers: Craig M. Tenney and Edward J. Maginn, “Limitations and recommendations for the calculation of shear viscosity using reverse nonequilibrium molecular dynamics”, Journal of Chemical Physics, 2010, 132, 014103; Saivenkataraman Jayaraman, Aidan P. Thompson, Anatole von Lilienfeld, and Edward J. Maginn, “Molecular Simulation of the Thermal and Transport Properties of Three Alkali Nitrate Salts”, Industrial and Engineering Chemistry Research, 2010, 49, 559-571; Manish S. Kelkar and Edward J. Maginn, “Effect of Temperature and Water Content on the Shear Viscosity of the Ionic Liquid 1-ethyl-3-methylimidazolium Bis(trifluoromethanesulfonyl)imide As Studied by Atomistic Simulations”, Journal of Physical Chemistry B, 2007, 111, 4867-4876.
(If the movie doesn't load in your browser, you can access it by clicking this link. You will need a Box account.)
Visualization support provided by Kristina Davis. Funding provided by the Department of Energy (DE-FC26-07NT43091) and (DE-AR0000119).
How does CO2 capture work?
CO2 can be captured from combustion gases by contacting the gas with a solvent designed to selectively remove CO2 from the other species present (mainly N2, O2 and H2O). Traditionally, aqueous amines are used, but they have many drawbacks including volatility, corrosivity, and a high thermal energy penalty for regeneration. We are developing new ionic liquid solvents for CO2 capture that do not suffer from these drawbacks. The animation below shows how the process works.
Using ionic liquids and CO2 in refrigeration cycles
Traditional vapor compression cooling cycles utilize fluorinated molecules as the refrigerant. While these compounds work well, they also have extremely high global warming potentials due to their absorption characteristics and long lifetime in the atmosphere. In principle, one could use CO2 as a refrigerant, but performance is poor. Using knowledge gained in our CO2 capture work with ionic liquids, we are working on the development of CO2/ionic liquid co-fluid cooling cycles. The animation below describes the idea. Funding provided by the Building Energy Efficiency Through Innovative Thermodevices (BEETIT) program of the Department of Energy ARPA-E program (DE-FOA-0000289). The project is led by Prof. Bill Schneider at Notre Dame.