Characteristics of used lubricating oils, their environmental impact and survey of disposal methods

Studies samples of different used lubricating oils. Details how their physico‐chemical characteristics were determined by the use of modern instrumental analytical techniques; and how different standard separation techniques were used to separate the unused base oil and other components from the collected samples for characterization. Discusses the different re‐refining procedures available in the literature and highlights the merits and demerits of different re‐refining techniques. Concludes that re‐refining of used oil will conserve resources and help to preserve the environment.