Production of Base Oil from Used Engine Oil Using Vacuum Distillation and Clay Treatment Method

Abstract The improper disposal of used engine oil presents significant environmental challenges, including soil and water contamination, highlighting the need for an effective recycling solution. This study explores the production of base oil from used engine oil using vacuum distillation combined with clay treatment, aimed at providing an environmentally friendly product through an efficient recycling method. Vacuum distillation was employed as the first step to remove water, light fractions, and impurities, ensuring minimal thermal degradation. The distillate was then treated using three types of clay—commercial-grade, untreated natural, and acid-activated natural clay—to eliminate residual impurities and enhance the physicochemical properties of the base oil. To characterize the treated base oil, FTIR spectroscopy was conducted alongside physicochemical tests to evaluate properties such as density, viscosity, flash point, pour point, sulfur content, and color. The FTIR analysis confirmed the removal of polar compounds and oxidized impurities, demonstrating the effectiveness of the treatment. The results showed that vacuum distillation, combined with acid-activated clay, yielded base oil with significantly improved properties, including reduced sulfur content (0.014%), higher flash point (236.4°C), and enhanced fluidity. Among the clays tested, acid-activated clay exhibited superior adsorption performance due to its increased surface area and porosity. The overall base oil yield was 42%, indicating the efficiency of the process. This study concludes that the combined approach of vacuum distillation and clay treatment is an effective and sustainable method for recycling used engine oil. This approach minimizes hazardous waste, reduces dependence on virgin crude oil, and promotes sustainable waste management practices. The findings underscore the potential of this method as a scalable solution for addressing the environmental challenges associated with used oil disposal.