Re–Refining of Used Lube Oils and Sustainability

As petroleum products continue to be an inseparable part of our lives, so does the waste that is generated from these products, the prominent among them being the used lubricating oil. However, research shows that more than half of the used lube oil can be converted back to usable lubricant through the process of re–refining. This can certainly reduce the amount of waste oil in the environment and the need of crude oil extraction to a certain extent. As there are various different methods of re–refining, this work focused specifically on the method used widely in India, i.e., Vacuum distillation with Clay treatment. In this paper, the sustainability of the re–refining process was checked using the green chemistry principles and overall material balance of the process. Based on the assumptions made for the material balance, nearly 69.92% of lube oil base stock was obtained along with 11.13% fuel by - product and 12.14% residue, both of which have varied uses in the industry, thus producing additional profit.