Prediction of vapor–liquid equilibria of alcohol+hydrocarbon systems by 1H NMR spectroscopy

The 1H NMR chemical shifts of alcohol+hydrocarbon systems over the whole concentration range at 298.15 K were measured. Based on the concept of local composition (LC), the concentration-dependent 1H NMR chemical shift data of the OH and CH groups for 13 alcohol+hydrocarbon systems were correlated with only one energy parameter, respectively. Using the parameters obtained from the spectra alone, the isothermal and isobaric vapor–liquid equilibria (VLE) data of the above-mentioned alcohol+hydrocarbon systems were predicted with satisfactory results. By this way, the spectroscopic information can be used to predict VLE data of alcohol+hydrocarbon systems directly.

► 1H NMR chemical shifts of alcohol+hydrocarbon systems at 298.15 K were measured.
► 1H NMR chemical shifts of the OH and CH groups were correlated by local composition model.
► The VLE data of alcohol+hydrocarbon systems was predicted by 1H NMR spectroscopy.
► The relationships between 1H NMR spectra and thermodynamic property were established.