RUI: The Role of Solvent Density and Solvation on the Enol-Keto Tautomerism in Supercritical Fluid Solvents.

Tuskegee University, Tuskegee Institute AL

Investigators

Abstract

The overall objective of the proposed project is to understand the molecular interaction between solute and supercritical fluid (SCFs) solvents. Both experimental techniques and a theoretical approach will be applied to investigate the role of solvent density and solvation in enol-keto tautomerism. The objectives of this work are: 1) The enol-keto tautomeric equilibrium constant in supercritical carbon dioxide and ethane will be estimated by using Fourier Transform infrared spectroscopy. The density of solvent will be adjusted by varying the temperature and pressure to investigate the effect of density on enol-keto tautomerism. 2) The role of solvation will also be investigated by comparing the tautomeric equilibrium constants in supercritical carbon dioxide with those in supercritical ethane. The quadrapole moment for carbon dioxide may lead to a chemical interaction with solutes (mono- and bicarbonyl compounds). 3) Theoretical tautomeric equilibrium constants in SCF solvent will be determined by using the lattice fluid hydrogen bonding model. The modeling work will reflect the interactions between solute and solvent in a quantitative manner. The significance of this proposed research is that it is likely to produce an expansion of the potential uses of SCFs as a means of reaction and as extraction media. This is based on increasing our understanding of the molecular interactions between solute and solvent, which is critical for the application of SCF solvents towards biotechnology, nano-particle and composite materials, remediation of waste materials, and the design and synthesis of multi-functional polymers.