# Management of Plastic Wastes through Recent Advanced Pyrolysis Processes
## 3 Recent Advances in Fuel Production from Plastic Pyrolysis
[51] conducted a study to characterize and evaluate plastic oil produced from the pyrolysis of mixed plastic waste as an alternative to diesel oil. The mixed plastic waste consisted of bread bags, glasses, polyethylene carry bags, plastic bottle folders, plastic file spoons, cable covers, and pet bottles. The pyrolysis reactor was designed to handle high temperatures, between 340 \({}^{\circ}\)C and 440 \({}^{\circ}\)C, and corrosive chemicals. Thermal breakdown of the mixed plastic waste at an optimal temperature produces volatile matter which, when condensed, results in plastic oil. The maximum yield of the pyrolysis process was obtained at 425 \({}^{\circ}\)C, which was nearly 80%. The heating value of the sample's fuel was found to be 42.58 MJ kg\({}^{-1}\), which is very similar to that of diesel (44.27 MJ kg\({}^{-1}\)), which supports the use of plastic oil in several industries. The plastic oil produced consisted of around 15 different hydrocarbons and had nearly the same physical characteristics as diesel. However, commercial fuel had lower viscosity than plastic oil obtained in this study. The reason for this higher viscosity might be because of the presence of light and heavy naptha in the oil sample. Also, the average density of the study's different oil samples was 783 kg/m\({}^{3}\), which is similar to that of diesel (837 kg/m\({}^{3}\)). The plastic oil was composed mainly of aliphatic hydrocarbons, ranging from C9 to C17. 1-decene and 1-hexadecene had the highest weight fraction in the liquid fuel. The study stated that fuel produced from plastic waste has high combustion capabilities. Also, the fuel includes hydrocarbons found mainly in gasoline instead of the diesel-range composition. Based on the analysis of the plastic oil, it was concluded that this oil may be used as a source of heat and energy production. The above discussion reveals the diverse pyrolysis methodologies and outcomes in converting plastic waste into valuable fuel oil. It was observed that the type of plastic feedstock significantly affects the liquid yield. Among the different types of plastic, PS and PP produced the highest liquid oil yield, followed by HDPE and LDEP, while PET showed the lowest yield. Also, it was observed that PP, HDPE, and LDPE are frequently studied due to their prevalence in waste streams. Moreover, recent advances in pyrolysis systems such as continuous microwave-assisted pyrolysis and plasma reactors achieve higher yields but require more complex equipment. In contrast, batch and fixed-bed reactors, while simpler, offer varied results based on the feedstock and operating conditions. Analysis of the operating factors like feed rate, temperature, and residence time showed that regarding the type of plastic, the optimum conditions to achieve the highest liquid oil yield would be changed accordingly. Catalysts, especially zeolites, significantly enhance the liquid oil yield and quality. Studies also showed the diverse applications for pyrolysis oil, including fuel oil, aviation oil, and hydrogen-rich fuel gas. However, economic and regulatory challenges persist, with high operational costs and strict compliance requirements. Addressing these challenges by improving reactor design, catalyst quality, and operating conditions would advance plastic pyrolysis as a sustainable waste management solution