Proton NMR characterization of gasoline–ethanol blends

• 1H NMR NORD spectra give water concentration in gasoline–ethanol blends.
• Ethanol content can also be easily measured.
• PFG NMR provides information on sizes of ethanol–water clusters.
• PFG NMR can be used to measure viscosity of fuel blends.

Nuclear magnetic resonance (NMR) can be conveniently used for accurate measurement of water and ethanol concentrations in gasoline–ethanol fuel blends. The spectra also contain information on proton exchange rates. In addition, NMR pulsed-field-gradient diffusion measurement allows estimation of ethanol–water clusters and viscosity of the fuel blends.