1H low- and high-field NMR study of the effects of plasma treatment on the oil and water fractions in crude heavy oil

► Study of crude and plasma-treated heavy oils naturally containing emulsified water. ► 1H low- and high-field NMR allowed detailed assessment of plasma treatment effects. ► Oil viscosity was reduced after plasma-treatments. ► Effects on water and oil portions were separately analyzed by NMR. ► Good correlation observed between viscosity and T2 of the oil fraction.