Impact of Plastic Blends on the Gaseous Product Composition from the Co-Pyrolysis Process

The co-pyrolysis of various biomasses mixed with two types of plastic waste was investigated in this study. Mixture M1 consisted of 30% m/m styrene–butadiene rubber (SBR), 40% m/m polyethylene terephthalate (PET), and 30% m/m polypropylene (PP). M2 consisted of 40% m/m PET, 30% m/m PP, and 30% m/m acrylonitrile–butadiene–styrene copolymer (ABS). The SBR, ABS, and PP used in this study were from the automotive industry, while the PET originated from scrap bottles. Co-pyrolysis was performed using wood biomass, agricultural biomass, and furniture trash. Thermal treatment was performed on samples from room temperature to 400 or 600 °C at a heating rate of 10 °C/min under N₂ at a flow rate of 3 dm³/min. Based on the findings of the experiments, an acceptable temperature was found for the fixed-bed pyrolysis of biomass–plastic mixtures with varying ratios, and the raw materials were pyrolyzed under the same conditions. The composition of the derived gaseous fraction was investigated. The co-pyrolysis studies and variance analysis revealed that combining biomass with plastic materials had a good influence on the gaseous fraction, particularly in the presence of 6.6–7.5% v/v hydrogen and a lower heating value of 15.11 MJ/m³. This type of gaseous product has great potential for use as a replacement for coke oven gas in metallurgy and other applications.