Balancing the Aromatic and Ketone Content of Bio-oils as Rejuvenators to Enhance Their Efficacy in Restoring Properties of Aged Bitumen

Abstract

The potential of the bio-oil from the co-pyrolysis of poplar wood and waste tire rubber to revitalize severely aged bitumen was examined by shifting the balance of aromatics and ketones in the bio-oil. Laboratory experiments were performed to compare the revitalization efficiency of bio-oils from the pyrolysis of poplar wood and co-pyrolysis of wood and waste tire rubber. Furthermore, the chemical compositions of the bio-oils from both processes were studied using gas chromatography−mass spectrometry to distinguish how each bio-oil revitalized severely aged bitumen. The results showed that the wood pyrolysis bio-oil had high phenol and ketone relative contents but very low aromatic and alkane relative contents. In contrast, significant relative amounts (19.18%) of aromatics and alkanes and a lower ketone relative content (0.95%) were found in the co-pyrolysis bio-oil. The rheological characterization of aged bitumen rejuvenated with both bio-oils showed that the co-pyrolysis bio-oil was much more effective than the wood pyrolysis bio-oil, which was evidenced by a higher crossover modulus and frequency as well as lower shear thinning in the aged bitumen rejuvenated by the co-pyrolysis bio-oil. These results prove that the co-pyrolysis bio-oil is a potential asphalt rejuvenator.

A Review on Virgin or Waste Polymers in Bitumen Modification for Ageing and Rejuvenation

“…Improved properties also include greater resistance to ageing and stability at high temperatures. The main reason for modifying bitumen with polymers can be summarized as follows 59: To make softer blends at low service temperatures and to reduce cracking To make stiffer blends at high temperatures and to reduce rutting To increase the stability and strength of the asphalt mixtures To improve the abrasion resistance of blends To decrease the oxidation of bitumen and improve ageing resistance To improve the fatigue resistance of blends To reduce the structural thickness of pavements To improve the efficiency and durability To reduce the life costs of the pavements …”

Future Directions for Applications of Bio-Oils in the Asphalt Industry: A Step to Sequester Carbon in Roadway Infrastructure

“…Li et al compared the effect of different compositions present in bio-oils on their performance. According to their results, they concluded that rejuvenators containing a high amount of aromatics and alkanes and a lower amount of ketones showed higher efficacy at restoring the properties of aged bitumen . Uz and Gokalp used waste vegetable cooking oil (sunflower oil) as an economical bio-oil to recover aged bitumen after both short-term and long-term aging.…”

Bio-Oil: The Next-Generation Source of Chemicals

“…Other works describe the utilization of bio-oil to produce polyols from which polyurethane foams are later achieved with increased tensile strength and thermal stability and higher biodegradability [141][142][143]. Bio-oil in bitumen applications is also reported to possibly increase bitumen performance and reduced binder consumption [3,116,[144][145][146][147][148][149].…”