Vacuum Residue as Antioxidant and Rejuvenator Agent for Bitumen

This research presents a laboratory study on a 100/130 bitumen treated with a vacuum residue (VR), i.e., the residue of vacuum distillation of oil, as a possible effective agent against bitumen aging. The VR was added to the bitumen before aging, in order to evaluate its antioxidant effect, and after aging to evaluate the rejuvenating effect. Several techniques were applied to investigate the mechanism of action of VR on the bitumen’s structure speculated to be antioxidant and/or rejuvenator. Mechanical properties were analyzed through dynamic shear rheometer (DSR), while the thermal characterization was done using the differential scanning calorimetry (DSC). Moreover, the chemical and morphological changes due to the addition of the VR were followed by Fourier transform infrared (FTIR) spectroscopy and by atomic force (AFM) and confocal microscopy. The obtained results showed that VR has strong antioxidant and noticeable rejuvenating effects.