Use of Char Derived from Waste Plastic Pyrolysis for Asphalt Binder Modification

Plastic waste management is posing a pressing challenge worldwide. Plastics take thousands of years to degrade naturally, and their disposal in landfills raises grave environmental concerns. Pyrolysis is gaining significant interest as a reliable method for management and energy valorization for plastic wastes. In addition to pyrolytic oil having good calorific value, waste plastic pyrolysis also yields solid char, as a by-product, which doesn’t find wide applications and is generally discarded. This study aims to evaluate the waste plastic pyrolytic char as an asphalt binder additive/modifier through different rheological and mechanical investigations. The modification of asphalt binder has been attempted at five char contents (0, 5, 10, 15 and 20% by binder weight). The rheological tests included flow behavior, frequency, and temperature sweeps, multiple stress creep recovery (MSCR). Zero shear viscosity was derived using the Cross model. Burger’s model was used to describe the MSCR response. Modified binders showed improved stiffness than the control binder indicating an improvement in their resistance against permanent deformation. The plastic char used in the study showed encouraging results and shows the potential to be used as an additive/modifier for asphalt binders.