摘要

The composition of asphalth as been the subject of much study because such data are required in determining its performance-related properties. A problem inherent in studying asphalt composition is its chemical complexity; however, the characterization of asphalt can be better achieved by separating into fractions. In this work, the chemical property of commercial-grade asphalt obtained from BAPCO refinery, Bahrain(BH), was carried out. The rolling thin-film oven(RTFO), used for short-termaging, and pressurized aging vessel (PAV), used for long-term aging, ASTMD 4124 (1991) method was used to separate fresh and aged asphalt into four generic fractions such as asphaltenes, polar aromatics, naphthene aromatics, and saturates. The Corbett fractionation procedure was used to separate fresh and aged asphalt into four generic fractions such as asphaltenes, polar aromatics, naphthene aromatics, and saturates. Nuclear magnetic resonance (NMR) was employed to finger print the chemical changes that occurred in asphalt during the aging processes. NMR measurements of asphalt fractions showed that during aging, isomerization and dehydrogenation types of reactions took place. Significant differences were observed between the structure and composition of fresh and aged fractions of asphalt. Results from NMR spectrometry provided significant information concerning the chemical transformations that occurred during the aging processes