**Experimental Study on the Performance of an SI Engine Fueled by Waste Plastic Pyrolysis Oil–Gasoline Blends**

**Khairil 1,\*, Teuku Meurah Indra Riayatsyah 1, Samsul Bahri 1, Sarwo Edhy Sofyan 1, Jalaluddin Jalaluddin 1, Fitranto Kusumo 2, Arridina Susan Silitonga 2,3, Yanti Padli 4, Muhammad Jihad <sup>1</sup> and Abd Halim Shamsuddin <sup>2</sup>**


Received: 27 May 2020; Accepted: 7 August 2020; Published: 14 August 2020

**Abstract:** Pyrolyzed waste plastic-based green fuel has been reported to be used as an alternate fuel for diesel engines. Some of the main challenges for implementing this in current automotive technology include evaluating engine performance, emission, noise vibration harshness (NVH), and knock characteristics of this fuel. This study focuses on the engine performance of poly-ethylene terephthalate (PET)-based waste plastic oil (WPO) at varying engine speed conditions. The pyrolysis of mixed-waste plastic was carried out at 300 ◦C in a fixed-bed reactor. Physicochemical properties such as viscosity, density, calorific value, sulfur, and research octane number (RON) of the plastic fuel and its blends with gasoline were analyzed using ASTM standard test methods. The WPO was blended with two different types of gasoline (RON88 and RON90) at 10, 20, and 30%, and was tested in a spark-ignition (SI) engine. The experimental results showed that different WPO–gasoline blends can be used in an SI engine without any engine modifications, and the performance indicators for different blends were found to be close to that of pure gasoline. The brake power and brake specific fuel consumption (BSFC) were found to be 4.1 kW and 0.309 kg/kW h, respectively. The 10% WPO and 90% RON90 blend produced optimal engine performance at 3500 rpm.

**Keywords:** waste plastic oil (WPO); engine performance; renewable gasoline; pyrolysis
