# Management of Plastic Wastes through Recent Advanced Pyrolysis Processes
## 3 Recent Advances in Fuel Production from Plastic Pyrolysis
The GandALF was able to achieve a similar model accuracy only after ten experiments compared to the regular design of experiments (DoE) after 18 experiments. The reduction in the number of experiments corresponds to a large reduction in cost, time, and effort. Investigating the effect of the catalyst showed that using HZSM-5 achieved higher yields between 7.2 wt% and 41.6 wt%, as opposed to using SAPO-34 (0.5\(-\)21.8 wt%). The results also showed that increasing the catalyst temperature and space-time elevates the ethylene and propylene production for both catalysts. The GandALF has proven to be more efficient than regular DoE methods for the development of a model for catalytic pyrolysis of LDPE. **Pyrolysis Modeling and Simulation:** [PERSON] et al. [46] also developed a comprehensive mathematical model to predict the catalytic pyrolysis of healthcare plastic waste for fuel production. The pyrolysis process is conducted in a fluidized-bed reactor using a ZSM-5 catalyst in conjunction with a microwave-assisted pyrolysis (MAP) system. A transient numerical analysis of the process was performed by using a lumped kinetic model that considers three lumped pyrolysis products, namely paraffin, olefins, and aromatics, coupled with the governing equations describing the process. The study examined the effect of different factors on the rate of consumption and production in the pyrolysis reactions using \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Type of Plastic** & **Type of Reactor** & **Pyrolysis Oil** & **Optimum Process Conditions** & **Type of Catalyst** & **Pyrolysis Oil** & **References** \\
**Waste Used** & **Used** & **Vield** & **Optimum Process Conditions** & **(If Used)** & **Application** & **References** \\ \hline PS, PE, PE, PVC, and PET & — & — & DT algorithm prediction & — & diesel and gasoline & [47] \\ \hline PS & PS & Batch unstrred & 85.20\% & & & & \\
25 wt% HDPE & tank reactor & 83.00\% & & & & \\ \hline PP & Semi-batch & & & & & \\  & pyrolytic & 89.34\% & & & & \\  & fixed-bed reactor & & & & & \\ \hline Plastic bags & Fixed-bed reactor & & & & & \\  & having two & 70.60\% & & & & \\  & condensers & & & & & \\ \hline Mixed plastic & & & & & & \\  & waste (glasses, & & & & & \\  & polyethylene being bags, & & & & & \\  & plastic bottle & & & & & \\  & folders, etc.) & & & & & \\ \hline LDPE and HDPE & \
\begin{tabular}{c} Batch catalytic \\ reactor \\ \end{tabular} & 73.00\% & & 280 °C & Catalyst & Alkyl aromatics & [52] \\ \hline LDPE & Batch reactor & 67.30\% & & & & & \\ \hline Plastic grocery & Batch reactor & 44.10\% & & & & \\  & bags & & & & & \\ \hline PE & Plasma reactor & 70.00\% & & & & \\  & fixed-bed reactor & — & & & \\ \hline \hline HDPE bottle caps &
\begin{tabular}{c} Laboratory-scale \\ fixed-bed reactor \\ \end{tabular} & — & 450 °C and 30 min residence time & — & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 2: _Cont._MAP. The factors of interest included the fluidizing-gas inlet velocity, the microwave power input, and the mass and particle size of the ZSM-5 catalyst. The accuracy of the MAP model was validated by comparing the numerically simulated temperature results against the experimental data. There was a close correlation between experimental temperature outcomes and the numerical predictions, with a difference of less than 5%. The mass and particle size of the catalyst used also have a significant impact on the yield of olefins, paraffins, and aromatics. The results showed that decreasing the catalyst's particle size generally increases the reaction rate, facilitating the production of paraffins, olefins, aromatics, and coke. However, using a catalyst with a particle size of less than 50 \(\upmu\)m was not applicable in the fluidized bed because of increased intermolecular forces. On the other hand, increasing the mass of the catalyst over 5 g did not have a significant influence on the reaction rate.