Effect of plastic pyrolytic oil and waste cooking biodiesel on tribological properties of palm biodiesel-diesel fuel blends

• Main Authors: Awang, Muhamad Sharul Nizam, Zulkifli, Nurin Wahidah Mohd, Mujtaba, M.A., Zulkifli, Muhammad Syahir Amzar, Kalam, Md. Abul, Mohd Yusoff, Mohd Nur Ashraf, Ahmad, Muhammad Hazwan, Wan Daud, Wan Mohd Ashri
• Format: Article
• Language: English
• Published: Emerald 2022
• Subjects: TJ Mechanical engineering and machinery
• Online Access: http://eprints.um.edu.my/28884/1/PDF_Proof.PDF; http://eprints.um.edu.my/28884/; http://dx.doi.org/10.1108/ILT-08-2021-0338

The purpose of this work was to investigate the lubricity of palm biodiesel (PB)-diesel fuel with plastic pyrolysis oil (PPO) and waste cooking biodiesel (WCB). Three quaternary fuels were prepared by mechanical stirring. B10 (10% PB in diesel) fuel was blended with 5, 10, and 15% of both PPO and WCB. The results were compared to B30 (30% PB in diesel) and B10. The lubricity of fuel samples was determined using high frequency reciprocating rig (HFRR) in accordance with ASTM D6079. The tribological behavior of all fuels was assessed by using scanning electron microscopy (SEM) on worn steel plates to determine wear scar diameter (WSD) and surface morphology. The reported wear scar diameter (WSD) is the average of the major and minor axis of the wear scar. The addition of PPO and WCB to B10 had improved its lubricity while lowering wear and friction coefficients. Among the quaternary fuels, B40 showed the greatest reduction in coefficient of friction and WSD, with 7.63 and 44.5% respectively when compared to B10. When compared to B30a, the quaternary fuel mixes (B40, B30b, and B20) exhibited significant reduction in WSD by 49.66, 42.84, and 40.24%, respectively. Among the quaternary fuels, B40 exhibited the best overall lubricating performance, which was supported by surface morphology analysis. The evaluation of B40 indicated a reduced adhesive wear and tribo-oxidation, as well as a smoother metal surface, as compared to B20 and B30b. Incorporation of PPO and WCB in PB-diesel blend as a quaternary fuel blend in diesel engines has not been reported. Only a few researchers looked into the impact of PPO and WCB on the lubricity of the fuel.