# Management of Plastic Wastes through Recent Advanced Pyrolysis Processes
## 3 Recent Advances in Fuel Production from Plastic Pyrolysis
Plastic packaging of instant noodles was chosen as a source of PP, while clear plastic bags were used as a source of HDPE. The pyrolysis was carried out in a batch reactor, heating up to 400 \({}^{\circ}\)C. The evaluation of the catalytic properties of natural zeolite was also carried out with various reaction conditions and different concentrations of zeolite catalysts of 1%, 3%, 5%, 7%, and 9% \(w/w\). The optimum pyrolysis conditions were obtained with catalyst concentrations of 7% for PP and 3% for HDPE (\(w/w\)), yielding 65.60% and 69.69% liquid fractions from HDPE and PP, respectively. When pyrolysis was carried out without the catalyst, only a small yield of 29.40% and 12.02% liquid fractions was obtained from PP and HDPE, respectively. Moreover, the use of the zeolite catalyst reduced the reaction temperature and time of the process. The reaction time needed for the process without a catalyst was 149 min for the PP sample and 192 min for the HDPE sample. However, when the catalyst was used, the reaction time decreased to 105 min for the PP sample and 132 min for the HDPE sample. The composition of the liquid product from the PP sample is different from the HDPE sample. The distribution of pyrolysis liquid of PP was rich in hydrocarbons of C5-C12,followed by C17-C20, and the lowest was C13-C16. This distribution indicates that the pyrolysis liquid consists mainly of a light (gasoline) fraction and a small fraction of diesel (C18-C28). In contrast, the pyrolysis liquid of HDPE has a distribution of 30.36% for C5-C12, 40.39% for C13-C16, 24.69% for C17-C20, and 4.5% for longer chains (>C20). The analysis showed that approximately 70% of the hydrocarbons of HDPE pyrolysis liquid are distributed in the gasoline and diesel range. Natural zeolite demonstrated reliable catalytic performance in producing hydrocarbon liquid from the pyrolysis of HDPE and PP plastic samples with high yields and shorter reaction times. **Pyrolysis-MIL-53 (Cu)-loaded Zeolite Y catalyst:** A more recent study [40] aimed to improve the limitations of zeolites in catalytic pyrolysis by loading MIL-53 (Cu) onto the zeolite's surface. The plastic feed used in this study was a mixture of HDPE, LDPE, PS, and PP. MIL-53 and zeolite Y were synthesized, mixed, and pyrolyzed in a reactor to obtain the catalyst. The pyrolysis process took place in a fixed bed reactor under laboratory pressure conditions. The effect of reactor temperature, catalyst loading, and crystallinity on the production of liquid oil was investigated using a response surface approach. The results revealed that the modified zeolite catalyst behaves similarly to expensive and noble metals because of its high electron-transfer density. Moreover, the obtained liquid oil was separated into gasoline, diesel fractions, and jet fuel, and the effect of the tested parameters on the production of each type was determined. The overall percentage yield of the liquid oil was found to be 80.8% at a temperature of 450 \({}^{\circ}\)C. The liquid oil contained valuable light aromatics, making it suitable for several applications including transportation, pharmaceutical, chemical, and painting applications. Based on the experimental results, the highest gasoline yield of 41.4% was obtained at a temperature of 381 \({}^{\circ}\)C, with a catalyst crystallinity of 82%, and catalyst loading of 2.5%. However, a much higher yield of 73.1% for jet fuel was achieved at a temperature of 525 \({}^{\circ}\)C, with an amorphous catalyst loading of 2.5%. Finally, the highest yield of diesel of 36.7% was obtained when the temperature was at 523 \({}^{\circ}\)C, with a fully crystalline catalyst, and catalyst loading of 10.5%. This novel composite catalyst showed high performance in improving the pyrolysis process to produce high-quality fuel. **Pyrolysis Natural-Mineral Catalyst:** [PERSON] et al. [41] proposed a sustainable approach for the pyrolysis of plastic waste using a natural mineral catalyst without modification.