Microwave pyrolysis, a novel process for recycling waste automotive engine oil

Used automotive engine oil was treated using a microwave-induced pyrolysis process, with the intention of assessing the suitability of the process in recovering valuable products from this otherwise difficult to dispose of waste. The resulting pyrolysis gases were condensed into liquid oil; the yield and composition of the recovered oil and remaining incondensable gases were determined, and these were compared with those arising from fresh oil. Process temperature was shown to have a significant effect on the overall yield and formation of the recovered oils. The recovered liquid and gaseous pyrolysis products contained various light hydrocarbons which could be used as a valuable fuel and as an industrial feedstock. Our results indicate that microwave pyrolysis shows extreme promise as a means for disposing of problematic waste oil. The recovery of commercially valuable products shows advantage over traditional, more destructive disposal methods, and suggests excellent potential for scaling the process to the commercial level.