NMR Measurements of chemical theory equilibrium constants for hydrogen‐bonded solutions

Abstract

Although various chemical theories have often been used to characterize hydrogen-bonded systems with some success, they have been limited by the fact that the equilibrium constants were adjustable parameters. This paper reports a method to measure directly these constants by proton nuclear magnetic resonance spectroscopy. Results are reported for several systems and are used with a chemicalphysical theory to predict vapor-liquid equilibria.

Guidelines for NMR measurements for determination of high and low pKa values (IUPAC Technical Report)

“…Table 2 Dissociation constant of 0.1 mol dm -3 sucrose (HL) from 13 C NMR titration at 60 °C in 1 mol dm -3 NaCl/NaOH [31]. [32]. The best agreement has been demonstrated for systems studied by 13 C and 31 P NMR [28,29,33].…”

Development of the AVEC model for associating mixtures using NMR spectroscopy

“…Spectroscopic techniques allow one to probe solution behavior from a molecular perspective and have become increasingly common in recent years. Nuclear magnetic resonance in particular (Gutowsky and Saike, 1953; Foster and Fyfe, 1965;Bruno et al, 1983;Eckert et al, 1986;Karachewski et al, 1989) has been used quite successfully to probe the solution structure. In the NMR spectra, as the extent of hydrogen bonding changes so does the chemical shift of complex formation.…”

Pilot scale study and design of a granular activated carbon regeneration process using supercritical fluids

“…These so called chemical-physical models are very versatile but suffer from too many adjustable parameters. It may be possible to reduce the number of such parameters, however, by measuring equilibrium constants spectroscopically [21]. It is likely that the most profitable applications of SCF technology will need to make use of COSOlvent effects to "tailor" a solvent for a particular solute and this type of model will likely be useful in the development of these applications.…”