Assessment of the Physico-Chemical Properties of Waste Cooking Oil and Spent Coffee Grounds Oil for Potential Use as Asphalt Binder Rejuvenators

Recycling of waste is an optional approach across industries to reduce environmental harm and turn it into sustainable and valuable resource alternatives. This paper addresses recycling of food industry waste through exploring potential use to enhance damaged asphalt binder used in roadways. The two wastes, spent coffee grounds and waste cooking oil were subjected to different levels of oxidation after which their physical and chemical properties were analyzed. Results show that oxidation significantly affects the oils by increasing the release of fatty acids and breaking of double bonds. The latter, in addition to polymerization and release of high molecular weight compounds, increases the viscosities of the oils while retaining their Newtonian behavior. As such, oxidation may be able to effectively customize physicochemical properties of oils, namely viscosity, for their reported application as asphalt binder rejuvenators. The rejuvenated binder can then be reused in production of asphalt for low traffic roadways.