GOALI - Atomistic Simulations of the Physical Properties and Phase Behavior of Ionic Liquid / Gas Mixtures

University Of Notre Dame, Notre Dame IN

Investigators

Abstract

Maginn / Notre Dame (0651726) This environmentally-related GOALI project is a collaborative effort between Notre Dame and DuPont. The ultimate objective is to develop and commercialize ionic liquids whose properties are tuned for a number of potential processes involving hydrofluorocarbons (HFCs), including absorption cooling, gas separation and "green" processes for recycling HFCs. To achieve this objective, the investigators develop and apply computational methods to predict how physical properties and phase behavior of ionic liquid / HFC mixtures depend upon structure, chemical composition, and thermodynamic state point. Using this information in conjunction with experimental characterization studies, DuPont will synthesize and evaluate new ionic liquids whose properties are optimized for the specific commercial applications under investigation. This NSf project supports of all the computational parts of the project, including development of transferable force fields for ionic liquids and HFCs, development of efficient simulation methods for carrying out solubility calculations, and the calculation of absorption isotherms and other physical properties important for commercial application. DuPont will conduct all the experiments in support of the project and will share data with the modeling group at Notre Dame. Intellectual merit Ionic liquids are a relatively new material class with unique properties including non-volatility and excellent solvation capabilities. Interest in commercial use of ionic liquids in the chemical industry has skyrocketed, but commercialization is hampered by a lack of physical property data and our inability to understand and predict how properties can be changed through chemical and structural modification of the ionic liquid. The PIs seek to overcome these limitations via a combined molecular modeling and experimental study. They focus on the physical properties and phase behavior of ionic liquid / HFC mixtures, both because of the overall importance of HFCs to DuPont and the fact that two different DuPont business units have identified several potential commercial applications involving these mixtures. However, the results and simulation methods will be widely applicable to other gas / ionic liquid systems as well. The project provides an ideal mechanism to link fundamental modeling work from academia with experimental and commercial development activities of industry. Broader Impacts In addition to the obvious environmental and energy efficiency benefits that would result from a successful project, the research from this project will result in the development and dissemination of new force fields for ionic liquids and HFCs, as well as a new simulation method for computing gas and vapor solubilities in liquids. The method will be made accessible to the broader user community through incorporation in open source software. The graduate student assigned to the project will be trained in modeling and statistical mechanics, but will also hold internship positions at DuPont. During these internships, the student will carry out experimental studies in support of the project and learn first hand about industrial research. The investigators will continue our efforts at recruiting undergraduate and high school students to work on the project, paying special attention to attracting under-represented groups.