Extraction and Characterisation of Maltene from Virgin Asphalt as a Potential Rejuvenating Agent

Abstract

The wide application of reclaimed asphalt pavement (RAP) is hindered due to the highly brittle nature of the material, which contributes a major factor towards cracking-related distresses. While the utilisation of rejuvenating agents has been shown to enhance the flexibility of RAP, they also trigger certain negative effects on the performance of asphalt mixtures. In view of this, potential rejuvenators should be able to alter the rheological properties of asphalts to limit fatigue issues and enhance the potential of low-temperature cracking. Therefore, this study aimed to investigate the possibility of extraction and characterisation of maltene from virgin asphalt (VA) as a potential rejuvenating agent in RAP. Several physicochemical characteristics were examined, including density, viscosity, gas chromatography–mass spectrometry (GC–MS), Fourier-transform infrared (FTIR) spectroscopy, CHNS elemental analysis, and energy dispersive X-ray (EDX) analysis. Finally, the stiffness modulus characteristics of the different types of asphalt binders were evaluated at low and high temperatures. The results demonstrated that maltene was successfully extracted from VA using petroleum ether. In addition, the GC–MS showed that the extracted maltene contained polar and non-polar compounds with low molecular weights compared to VA. Furthermore, the spectra curve of maltene was very similar to that of asphalt, indicating its compatibility with asphalt binder and prospective use. Finally, adding maltene to aged asphalt decreased stiffness values to 0.0063, 0.0499, and 0.0108 MPa, which are equivalent to VA values (0.0061, 0.0481, and 0.0104 MPa) at loading times of 1.0, 0.1, and 0.55 s, respectively. Meanwhile, the stiffness modulus characteristics at low temperature were restored with the addition of maltene.

Effect of Warm Mix Asphalt (WMA) Antistripping Agent on Performance of Waste Engine Oil-Rejuvenated Asphalt Binders and Mixtures

“…The efficiency of the recycling agent in reducing the viscosity of an aged binder and restoring its rheological characteristics can be an indication of its effectiveness [7]. Rejuvenators could be petroleum-based, bio-based, waste-cookingor industrial-oil-based, or based on specially created additives from various sources of oil [8,9]. These rejuvenators can restore the asphaltenes/maltenes ratio in the asphalt binder, reducing the hardening impact of the old binder [10].…”

Fatigue Performance of Recycled Asphalt Mixtures: Viscoelastic Continuum Damage Approach and Cost Analysis

“…The origin and level of aging of the RAP influence the degree of binder activity (DoA) and availability (DoAv), which represent the minimum and maximum amount, respectively, of RAP binder that can be considered in a mixture design and are intrinsic properties of the material. The interaction of the RAP binder with virgin materials or rejuvenating agents is linked to a phenomenon called degree of binder blending (DoB) and describes the contribution of the RAP binder to the final properties of the recycled mix [10,21,22].…”