World Journal of Chemical Education
ISSN (Print): 2375-1665 ISSN (Online): 2375-1657 Website: http://www.sciepub.com/journal/wjce Editor-in-chief: Prof. V. Jagannadham
Open Access
Journal Browser
Go
World Journal of Chemical Education. 2019, 7(3), 189-195
DOI: 10.12691/wjce-7-3-1
Open AccessArticle

Application of Quantitative Proton Nuclear Magnetic Resonance Spectroscopy for the Compositional Analysis of Short Chain Fatty Acid Benzyl Ester Mixtures

Ronald P. D’Amelia1, , Joseph Mancuso1 and Nanette Wachter1

1Chemistry Department, Hofstra University, Hempstead, NY

Pub. Date: May 20, 2019

Cite this paper:
Ronald P. D’Amelia, Joseph Mancuso and Nanette Wachter. Application of Quantitative Proton Nuclear Magnetic Resonance Spectroscopy for the Compositional Analysis of Short Chain Fatty Acid Benzyl Ester Mixtures. World Journal of Chemical Education. 2019; 7(3):189-195. doi: 10.12691/wjce-7-3-1

Abstract

Nuclear Magnetic Resonance (NMR) has become one of the cornerstones of instrumental analysis work done in chemistry laboratories. NMR is most powerful when used quantitatively, the technique of using NMR to quantify the concentration of an analyte is referred to as qNMR and proton NMR, in particular, is extremely useful in this pursuit to quantify organic compounds. In order to increase exposure to the quantitative and qualitative aspects of NMR in the undergraduate chemistry laboratory, we have created a qNMR experiment to be used in analytical chemistry and instrumental analysis courses. The objective of the experiment was to determine the % composition of a two-component mixture of benzyl acetate (BA), benzyl propionate (BP), and benzyl butyrate (BB). We report on the methodologies used to determine % BA, BP, and BB. Mixtures ranged from 100% to 20%. The results show a strong linear relationship relating known weight %’s with qNMR weight %’s and serves as confirmation of the quantitative utility of proton NMR as well as an educational tool for the undergraduate chemical laboratory.

Keywords:
quantitative analysis Nuclear Magnetic Resonance undergraduate laboratory experiment hands-on learning benzyl esters benzyl ester mixtures

Creative CommonsThis work is licensed under a Creative Commons Attribution 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/

References:

[1]  Woodworth J.K., Terrance J.C., and Hoffmann M.M, “Using Nuclear Magnetic Resonance Spectroscopy for Measuring Ternary Phase Diagrams”, J. Chem. Educ., 83(7), 1065-1066, July 2006.
 
[2]  Isaac-Lam M.F., “Analysis of Bromination of Ethylbenzene using a 45 MHz NMR Spectrometer: An Undergraduate Organic Chemistry Laboratory Experiment”, J. Chem. Educ., 91, 1264-1266, July 2014.
 
[3]  McGregor, M.A., Euler, W.B. Undergraduate NMR Laboratory Experiments. In NMR Concepts; Traficante, D.D. Ed.; NMR Concepts: Warwick, RI, 1995.
 
[4]  Gift A.D., Stewart S.M., and Bokashanga K.P., Experimental Determination of pKa Values by use of NMR Chemical Shifts, Revisited”, J. Chem. Educ. 89, 1458-1460, August 2012.
 
[5]  D’Amelia, R; Huang, L; Nirode, W; Rotman, E; Shumila, J; Wachter, N; “Application of 1H-NMR for the Quantitative Analysis of Short Chain Fatty Acid Methyl Ester Mixtures: An Undergraduate Instrumental Analysis Experiment”, World Journal of Chemical Education, April 2015.
 
[6]  Hoffmann M.M., Caccamis J.T., Heitz M.P., and Schlecht K.D., “Quantitative Analysis of Nail Polish Remover using Nuclear Magnetic Resonance Spectroscopy Revisited”, J. Chem. Educ., 85(10), 1421-1423, October 2008.
 
[7]  Clarke, D., “Acetone and Ethyl Acetate in Commercial Nail Polish Removers: A Quantitative NMR Experiment using an Internal Standard”, J. Chem. Educ., 74(12), 1464-1465, December 1997.
 
[8]  Peterson, J., ”1H NMR Analysis of Mixtures using Internal Standards”, J. Chem. Educ., 69, 843-845, October 1992.
 
[9]  Bauner, B. and Pringle, D. “Proton NMR Analysis of Heat Exchange Fluids Containing Ethylene Glycol, Propylene Glycol, and Water: A Real-World Experiment for the Analytical Laboratory”, J. Chem. Educ., 91, 743-746, April 2014.
 
[10]  Phillips J.S., Leary J.J., “A Qualitative – Quantitative 1H- NMR Experiment for the Instrumental Analysis Laboratory”, J. Chem. Educ., 63(6), 545-546, June 1986.
 
[11]  Podgorski, V.V., Milhalev, A.S., Kalabin, G.A., “Quantitative NMR Spectroscopy for the Quality control of Drugs and Pharmaceuticals, Phar. Chem.J., 45(3), 194-197, June 2011.