Potential of tire pyrolysis oil as an alternate fuel for diesel engines: A review

The application of tire pyrolysis oil (TPO) as an alternative fuel has attained attention owing to the exponentially raise demand and price of fossil fuels, environmental impacts, and landfilling of the waste tires. Globally, the pyrolysis process has become the leading solution to this problem by converting the waste tires to the TPO. So, this review paper studies the application of TPO in diesel engines related to the purification and physicochemical properties of TPO with their effects on the combustion, performance, and emission characteristics of the fuel. Oxidative desulfurization and catalyst process is the most reliable method to remove the sulfur contents and purified the tire pyrolysis oil. Higher cylinder peak pressure, heat release rate, and ignition delay has been observed and noted its impact on the combustion analysis of the TPO. An increase in brake power, brake thermal efficiency, and lower brake specific fuel consumption have been found in the performance analysis of TPO. In emission analysis literature, mixed trends have been seen in nitrogen oxides and hydrocarbon emission, so in some cases, emission tends to increase, but the opposite direction has also been observed in other cases. Carbon monoxide and carbon dioxide and particulate matter emission are reduced owing to the excess of oxygen shares in TPO. In general, no alteration in the diesel engine is required for a low share of TPO in the TPO-diesel blend. Finally, it is concluded that the studies recommended the TPO-diesel (10%–90%) blend in the engine as an alternative fuel.