Rapid evaluation of asphaltene-paraffin content in crude oil by solid-state NMR

The paper presents results demonstrating, using a series of crude oil samples, the negative impact of resin glass transition effects on the accurate determination of the solid-state component of the NMR signal attributed to crystalline paraffins. To address this issue, a modified NMR-based method for quantifying paraffins and asphaltenes is proposed. The approach involves separating the crystallization temperature of paraffins from the glass transition temperature of resins by plasticizing the resins through the preliminary addition of a specific amount of solvent or precipitant to the crude oil.