Thermochemical process of polypropylene plastic waste recovered from electric and electronic apparatuses-to-clean hydrogen energy

This study investigates the thermochemical gasification of polypropylene plastic waste recovered from electronic and electrical apparatuses to produce clean hydrogen and syngas. A thermodynamic model was developed to simulate the gasification process using steam as the gasification agent. The model's accuracy was validated by comparing the syngas composition with experimental data from previous studies. The root mean square error (RMSE) of smaller than 2 confirmed the high precision of the model. The study explores the effects of key parameters-process temperature, steam-to-plastic waste ratio (SPWR), and moisture content-on the syngas composition. An increase in process temperature from 950 to 1250 K led to a rise in the molar percentage of H 2 from 64.86 % to 67.62 %, while CH 4 decreased from 4.50 % to nearly 0 %. A similar increase in CO from 21.32 % to 28.35 % was observed, while CO 2 decreased from 9.31 % to 4.02 %. Furthermore, increasing the SPWR from 1 to 3 resulted in a significant increase in H 2 from 58.47 % to 69.44 % and a decrease in CH 4 from 7.77 % to 0.04 %. Simultaneous optimization of temperature and SPWR further enhanced the molar percentage of H 2 by 36 %, from 51.30 % to 69.70 %. These results demonstrate that optimizing the gasification process by controlling temperature and SPWR is crucial for improving hydrogen yield and reducing methane and carbon dioxide emissions, contributing to cleaner energy production. • Thermochemical gasification of polypropylene waste to produce clean hydrogen. • High modeling accuracy with RMSE values of 0.456 and 1.906. • Increased process temperature boosts H 2 and CO, reduces CO 2 and CH 4 . • Optimizing steam-to-plastic waste ratio increases H 2 by 36 %. • Simultaneous optimization lowers CO 2 emissions and enhances process efficiency.