Utilizing Moringa and Sunflower Oils as Sustainable Additives for Reduced Viscosity and Lower Working Temperatures in Asphalt Binder

In efforts to mitigate greenhouse gas (GHG) emissions, the use of vegetable oils as additives in asphalt binders has gained significant interest. However, the limited availability of vegetable oil in certain regions poses challenges, as its use must not compromise critical applications like food production. To encourage the adoption of vegetable oils in asphalt pavements, it is crucial to diversify their use across different regions, such as Brazil, which offers favorable conditions for cultivating various oilseeds like soy, palm, cotton, sunflower, and moringa. This study aims to evaluate the effectiveness of incorporating moringa and sunflower oils at concentrations of 1%, 1.5%, 2%, and 2.5% by weight of the asphalt binder in reducing binder viscosity and achieving lower working temperatures during mixture preparation and compaction. An analysis of variance (ANOVA) was conducted to assess the significance of the data. The results demonstrate that incorporating vegetable oils reduced asphalt binder viscosity, mixing temperature, and compaction temperature. Moringa oil showed the most substantial reductions, with a decrease of 18.3°C in compaction temperature and 13.8°C in mixing temperature at a 2.5% concentration. Additionally, the use of vegetable oils effectively reduced the binder's susceptibility to aging while maintaining its resistance to permanent deformation. An optimal content of 2% vegetable oil was identified for pavement applications. This research highlights the potential of vegetable oils, particularly moringa and sunflower oils, as sustainable and effective additives for modifying asphalt binders, contributing to reduced environmental impact and promoting more sustainable infrastructure practices. Through blending charts, it was found that incorporating 2.5% of these vegetable oils allows the use of approximately 43% RAP in recycled asphalt mixtures.