Gel permeation chromatographic analysis of solubilized lignite asphaltenes and preasphaltenes

Abstract GPC data have been measured for a series of acetylated solvent refined lignite (SRL) asphaltenes and preasphaltenes and model compounds. Two structural parameters, the degree of aromatic condensation ( H aru C ar ) and the molar hydrogen to carbon ratio ( H C ), were employed to correct the molecular weight of the samples for linear molecular size. For the model compounds, H aru C ar was more effective, whereas the SRL materials were better adjusted by H C . The calibration standards deemed most suitable for determination of molecular weight of SRL by GPC are the SRL samples themselves.