An investigation into the influence of aging and rejuvenation on surface free energy components and chemical composition of bitumen. (10th June 2020) - Matolia, Sourabh
Highlights: Effectiveness of Waste Vegetable Oil as a rejuvenator for aged bitumen was evaluated. Relation between SFE components and SARA fractions in aged bitumen was evaluated. The aggregation of the asphaltenes in aged bitumen found to influence the trend of γ+−. γ LW correlates, inversely, well with asphaltenes concentration rather than γ Total (or) γ+−. Abstract: The present work aims to study the influence of Waste Vegetable Oil (WVO) as a rejuvenator on the properties (physical, chemical and surface free energy (SFE)) of aged bitumen and assess the interaction between rejuvenator and aged bitumen in such blends. The study also investigated the relation between SFE components and SARA (acronym for Saturates, Aromatics, Resins and Asphaltenes) fractions in aged and rejuvenated bitumen. The SARA analysis was carried out by employing Thin-layer chromatography with flame ionisation detection (TLC-FID) technique. The SFE components of the bitumen for both aged and rejuvenated bitumen were determined by measuring the contact angles with different probe liquids using a sessile drop device. The test results on bitumen aged to different construction and in-service conditions suggested that the non-polar component of SFE (γ LW ) decreases with aging, which is due to a decrease in non-polar saturates and aromatics as demonstrated by TLC-FID analysis. However, the increase of the polar asphaltenes was not reflected in the trend for the polar component of SFE (γ+−) which was attributed to the aggregation of the asphaltenes into clusters in extremely aged bitumen. The findings from the study also suggested that γ LW correlates, inversely, well with asphaltenes concentration rather than total SFE (γ Total ) (or) γ+−.