University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange Masters Theses Graduate School 12-2008 Heats of Solvation of Organic Liquids in Room Temperature Ionic Liquids Paula Jeanette Beach University of Tennessee - Knoxville Follow this and additional works at: https://trace.tennessee.edu/utk_gradthes Part of the Chemistry Commons Recommended Citation Beach, Paula Jeanette, "Heats of Solvation of Organic Liquids in Room Temperature Ionic Liquids. " Master's Thesis, University of Tennessee, 2008. https://trace.tennessee.edu/utk_gradthes/362 This Thesis is brought to you for free and open access by the Graduate School at TRACE: Tennessee Research and Creative Exchange. It has been accepted for inclusion in Masters Theses by an authorized administrator of TRACE: Tennessee Research and Creative Exchange. For more information, please contact [email protected]. To the Graduate Council: I am submitting herewith a thesis written by Paula Jeanette Beach entitled "Heats of Solvation of Organic Liquids in Room Temperature Ionic Liquids." I have examined the final electronic copy of this thesis for form and content and recommend that it be accepted in partial fulfillment of the requirements for the degree of Master of Science, with a major in Chemistry. John E. Bartmess, Major Professor We have read this thesis and recommend its acceptance: Michael Sepaniak, Jeffrey Kovac Accepted for the Council: Carolyn R. Hodges Vice Provost and Dean of the Graduate School (Original signatures are on file with official studentecor r ds.) To the Graduate Council: I am submitting herewith a thesis written by Paula Jeanette Beach entitled “Heats of Solvation of Organic Liquids in Room Temperature Ionic Liquids.” I have examined the final electronic copy of this thesis for form and content and recommend that it be accepted in partial fulfillment of the requirements for the degree of Master of Science, with a major in Chemistry. ___________________________ John E. Bartmess, Major Professor We have read this thesis and Recommend its acceptance: ___________________________ Michael Sepaniak ___________________________ Jeffrey Kovac Accepted for the council: _____________________________ Carolyn R. Hodges, Vice Provost and Dean of the Graduate School Heats of Solvation of Organic Liquids in Room Temperature Ionic Liquids A Thesis Presented for the Master of Science Degree The University of Tennessee Knoxville Paula Jeanette Beach December 2008 Abstract Ionic liquids are of potential use in industry as reusable, non-polluting solvents. Their thermochemical properties need to be known to facilitate planning of processes and experiments using these solvents. Two ionic liquids: 1-Butyl-3-methylimidazolium hexafluorophosphate ([C4mim]PF6 or [bmim]PF6) and 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([hmim]NTf2) were studied using a calorimeter. Various organic liquids were introduced into the solvents and their heats of solution were measured and tabulated. Potential effects of certain functional groups such as alcohol, amine, carboxylic acid, ketone, and aldehyde were examined as well as aromatics versus chains and saturated rings. ii Table of Contents Chapter Page 1. Introduction to Ionic Liquids and Calorimetry..........................1 A. Ionic Liquids..............................................................................................1 B. Calorimetry...............................................................................................1 C. Survey of relevant literature ...................................................................2 D. Explanation of current research ............................................................6 2. Procedure....................................................................................................7 A. Description of setup and equipment.......................................................7 B. Experimental Details..............................................................................13 1. Bmim(PF6):...............................................................................13 a) Distilled water..................................................................13 b) Methanol...........................................................................13 c) Cyclohexane .....................................................................13 d) Benzene.............................................................................15 e) Hexane..............................................................................15 f) Acetone .............................................................................15 g) Benzonitrile.......................................................................15 h) Acetonitrile.......................................................................17 2. [hmim]NTf2..................................................................................17 a) Comparison of Calorimeters............................................17 b) Examination of fresh vs. used solvent with benzene........17 iii Chapter Page c) Methanol...........................................................................17 d) Tetrahydrofuran................................................................17 e) Hexane..............................................................................18 f) m-Xylene............................................................................18 g) p-Xylene............................................................................18 h) Hexanol.............................................................................18 i) Cyclohexane......................................................................18 j) Acetonitrile........................................................................19 k) Aniline...............................................................................19 l) Acetone..............................................................................19 m) Pyridine............................................................................19 n) Hexafluorobenzene...........................................................19 o) 3-pentanone......................................................................19 p) Acetic acid........................................................................19 q) N,N-dimethylaniline.........................................................20 r) Ethanol..............................................................................20 s) Trichloromethane..............................................................20 t) Benzonitrile.......................................................................20 u) Butanol..............................................................................20 v) t-Butyl alcohol...................................................................20 w) Valeraldehyde..................................................................20 x) o-xylene.............................................................................21 iv Chapter Page y) 1,1,1,3,3,3-Hexafluoro-2-propanol.................................21 z) Trifluoroacetic acid...........................................................21 aa) Dioxane...........................................................................21 bb) Retry of benzene in same sample of solvent to check for stacking..........................................................................21 3. Dioxane in water...................................................................................21 3. Results and Discussion.........................................................................22 A. Background.............................................................................................22 B. Discussion of Results in [hmim]NTf2....................................................26 1. Alcohols.....................................................................................26 2. Anilines.........................................................................................26 3. Acids..............................................................................................28 4. Aromatics......................................................................................28 5. Ring Ethers................................................................................28 6. Ketones.........................................................................................28 7. Alkanes.........................................................................................28 8. Other.............................................................................................29 C. Discussion of Results in [bmim]PF6......................................................29 D. Calculations.............................................................................................30 E. Comparison of IL with Water................................................................30 v Chapter Page 1. Aromatics......................................................................................36 2. Protic Compounds.......................................................................36 3. Fluorinated Compounds.............................................................37 4. Ring Ethers..................................................................................37 5. Ketones.........................................................................................37 6. Aniline...........................................................................................38 F. Future Research.......................................................................................38