Keynote Address:

USING IONIC LIQUIDS FOR ENERGY APPLICATIONS

Ionic liquids (ILs) are organic salts that have sufficiently low melting points that, in their pure state, they are liquid around room temperature. Typical compounds are comprised of a quaternary ammonium, quaternary phosphonium, imidazolium or pyridinium cation with a wide variety of common anions. Since they are salts they have negligible vapor pressure so they do not evaporate and cause air pollution. We will discuss typical properties of ILs and, more importantly, how those properties can be tuned by the choice of cation, anion and substituents. Our emphasis is on the development of ILs for a variety of important energy-related applications.  In particular, we will discuss work on the design of ILs for gas separations, including removal of CO2 from post-combustion flue gas, pre-combustion gases, and natural gas. In some of these applications it is necessary to increase capacity and selectivity by including amine functionality in the ILs so that they can chemically react with CO2. We show how the use of amine functionalized aprotic heterocyclic anions can achieve 1:1 uptake with tunable reaction enthalpy and without increases in viscosity. We will also discuss the use of ILs for CO2/IL co-fluid vapor compression refrigeration. This system offers environmental advantages over conventional technology while improving coefficients of performance. Finally, we will show how the structure of the anion and cation can improve the ‘ionicity’ of ILs. This is important in the use of ILs as electrolytes for a wide variety of electrochemical applications, including lithium-ion batteries, dye sensitized solar cells, supercapacitors and electroplating.

The Cary Lecture Series in the School of Chemical & Biomolecular Engineering was established in 1984 as a memorial to Ashton Hall Cary, a chemical engineering graduate of Georgia Tech, Class of 1943. Mr. Cary served in the U.S. Army after graduation and later built a career in Georgia’s textile industry. He was a native of LaGrange, Georgia, where he was prominent in local politics and business and active in many charitable and civic organizations. At the time of his death in 1983, Mr. Cary was a production consultant for Kleen-Tex Industries.

The Cary Lecture Series was initiated with a gift from Dr. Freeman Cary, who also studied chemical engineering at Tech. Dr. Cary, who is Ashton’s brother, received his M.D. from Emory University in 1950 and later became the attending physician for the U.S. Congress. The Cary Lectureship Fund is used to sponsor a lecture series by distinguished scholars in fields of significance to chemical engineering. The visiting lecturers, in addition to presenting seminars on recent engineering advances, participate in informal discussions with Georgia Tech faculty and students.