Epoxidation of waste cooking oil and its use as a reactive modifier for bitumen

This method describes the conversion of waste cooking oil into a reactive bio-based modifier for bitumen through epoxidation, followed by curing with diethylenetriamine. The epoxidation efficiency was evaluated using iodine and epoxy values and confirmed by Fourier-transform infrared spectroscopy. The resulting epoxidized waste cooking oil was incorporated into 70/100 penetration-grade bitumen, and the development of the internal structure was monitored by dynamic shear rheometry during curing at 120 and 180 °C. The rheological rutting resistance parameter G*/sin(δ) and the continuous high-temperature performance grade were used to assess curing kinetics. The results showed almost complete conversion of carbon-carbon double bonds into epoxy groups and progressive stiffening of the modified binder. Structuring proceeded most rapidly during the first 24 h and was accelerated at 180 °C. The proposed method provides a reproducible approach for producing and evaluating a bio-modified asphalt binder derived from waste cooking oil. • Conversion of waste cooking oil into epoxidized waste cooking oil. • Curing of the bitumen- epoxidized waste cooking oil system with diethylenetriamine. • Rheological assessment of structuring and high-temperature performance.