Biomass waste to produce bio oil as rejuvenator for asphalt based on pyrolysis technology

The objective of the current study is to research the suitability of using two bio-oils produced from corncob and birch bark as two bio-rejuvenators to regenerate aged asphalt binders. To this end, the pyrolysis characteristics of corncob and birch bark were analysed using a thermogravimetric analyzer. The chemical characteristics of the bio-rejuvenators were then evaluated via an elemental analyzer and the Gas Chromatograph Mass Spectrometer (GC-MS) test. The results revealed the presence of a great quantity of lightly weighted compounds in bio-oils. Pen70 asphalt was used as control asphalt binders. The Rotational Viscometer (RV) test result showed that bio-rejuvenators could help reduce the viscosity of aged asphalt binders. In addition, the Dynamic Shear Rheometer (DSR) experiments revealed that bio-rejuvenators could reduce the complex shear modulus, decrease percent strain recovery, increase non-recoverable creep compliance and restore the fatigue performance of the aged asphalt. The Bending Beam Rheometer (BBR) tests indicated that the cracking performance of the bio-rejuvenated asphalt was also improved compared with the aged asphalt. The Fourier transform infrared spectra demonstrated that the bio-rejuvenators helped reduce the aged asphalt's carbonyl and sulfoxide indexes. In addition, the Gel Permeation Chromatography (GPC) test indicated that bio-rejuvenators reduced the polydispersity and molecular weight of the aged asphalt.