Hydrogen rich syngas and high-value biofuel production by pyrolysis of different biomass generations and waste plastics: theoretical investigation and feasibility assessment

In this study, a simulated model was developed using Aspen Plus software to investigate the pyrolysis of four different biomasses and waste plastics: Coconut shell (CS), Granular bacteria (GB), Azolla, and High-density polyethylene (HDPE). The primary goal was to produce valuable syngas and biofuel and analyze the impact of key operating conditions, temperature and pressure, on product distribution (bio oil, biogas, biochar), gaseous composition (H 2 , CO, CO 2 , CH 4 ), and the H 2 /CO ratio. The simulation results revealed that the highest bio oil yield (54 wt%) was obtained from High-density polyethylene at a temperature of 525 °C and pressure of 1 bar, while the maximum biogas yield (46 wt%) belonged to Azolla at a temperature of 600 °C and a pressure of 1 bar. The H 2 /CO ratio for all feeds decreased with increasing temperature but increased with rising pressure. High-density polyethylene consistently showed the highest H 2 /CO ratio, confirming its potential as an ideal feedstock for hydrogen-rich syngas production. These findings provide critical insights for optimizing the pyrolysis process and selecting suitable feedstocks for high-value biofuel production. This research offers a fundamental understanding for the design and optimization of industrial-scale pyrolysis reactors and contributes to the broader framework of the circular economy by demonstrating the feasibility of converting specific waste streams into valuable energy products.