Pyrolysis method recycles motor oil into fuel

Estimates suggest that changing the oil in cars and trucks produces about eight billion gallons of used motor oil each year around the world. In the US and some other countries, some of that dirty oil is collected and re-refined into new lubricating oil or processed and burned in furnaces to heat buildings. However, such uses are far from ideal because of concerns over environmental pollution from re-refining oil and burning waste oil.

’Transforming used motor oil into petrol can help solve two problems at once,’ said Howard Chase, professor of biochemical engineering at Cambridge University. ’It provides a new use for a waste material that’s too-often disposed of improperly, with harm to the environment. In addition, it provides a supplemental fuel source.’

One technique used to convert motor oil into fuel uses pyrolysis, a process that involves heating oil at high temperatures in the absence of oxygen. Pyrolysis breaks down the waste oil into a mix of gases, liquids, and a small amount of solids. The gases and liquids can then be chemically converted into gasoline or diesel fuel. However, the current processes heat the oil unevenly, producing gases and liquids not easily converted into fuel.