Group Type Analysis of Asphalt by Column Liquid Chromatography

Abstract

An improved analysis method for characterization of asphalt was established. The method is based on column chromatography technique. The asphalts were separated into four groups: saturates, aromatics, resins, and asphaltenes, quantitatively. About 0.1 g of sample was required in each analysis. About 20 mL of n-heptanes was used to separate out saturates first. Then about 35 mL of n-heptanes/dichloromethane (1/2.5, v/v) mixture was used to separate out aromatics. About 30 mL of dichloromethane/tetrahydrofuran (1/3, v/v) mixture was used to separate out resin. The quality of the separation was confirmed by infrared spectra (IR) and ¹H NMR analysis. The model compounds, tetracosan for saturates, dibenz(ah)anthracen for aromatics, and acetanilide for resins were used for verification. The IR and ¹H NMR analysis of the prepared fractions from the column liquid chromatography were in good agreement that of pure reagents.

Keywords:

• column liquid chromatography
• co-processing coal with petroleum
• group type analysis
• heavy asphalt

ACKNOWLEDGMENTS

The authors gratefully acknowledge the financial support from the Natural Science Foundation of China (90210034, 20276078) and the Special Funds for Major State Basic Research Project (973 Program, 2004CB217602).