Experimental study the effect of using fuels from pyrolysis of waste tire oil-diesel blends on the CI-engine performance

• WTO derived from waste tires pyrolysis. • WTO blends up to 50% with several grades of commercial fuels, maintaining competitive performance even at blends up to 30%. • SFC rises, thermal efficiency and power drop with WTO but remain feasible. • High WTO blends (50 %) with CN48 boost power, lower efficiency, promise low-grade fuel, and need optimization. • All WTO-diesel blends can be used as sustainable fuel. The objective of this study is to investigates the effect of using fuels from pyrolysis of waste tire oil-diesel blends on the CI-Engine performance. In this study used WTO composition blends of 10 %, 20 %, 30 %, 40 %, and 50 % with three diesel grades: Pertamina Dex (CN53), Dex-lite (CN51), and Bio-solar (CN48), as test fuels to evaluate engine power, specific fuel consumption (SFC), and thermal efficiency under various operating conditions. WTO was generated via pyrolysis of waste truck tires at 300 °C in a fixed-bed reactor. The physico-chemical properties of the WTO, including viscosity, density, calorific value, and cetane number, were analyzed using ASTM standards . The results showed that WTO-diesel blends can operate in a diesel engine without modifications. The addition of WTO content up to 30 % in CN53 resulted in an average SFC increase of 9 %, as well as reductions in power and thermal efficiency of 2.72 % and 3.7 %, respectively. Blending WTO with CN51 increased SFC by 7.96 % while decreasing power and thermal efficiency by 2.78 % and 3.7 %, respectively. Interestingly, the average power increased by 4.65 % when blending WTO with CN48 up to 50 % content. The fact that CN48 has significantly lower calorific values than WTO may account for these results. The study concludes that blending diesel fuel with up to 20 % WTO is optimal for CN53 and CN51 to maintain engine performance. Meanwhile, lower-grade diesel blends with up to 50 % WTO like CN48 offer promising and cost-effective alternative fuels. Despite challenges in combustion, fuel consumption and efficiency must be addressed in future works. These findings may provide valuable insights into WTO-diesel blends performance, supporting further research in sustainable fuel technology and renewable energy regulations.