Co-pyrolysis and Cl release characteristics of PVC and lignocellulose

To elucidate the pyrolysis characteristics and Cl release law of domestic dry waste, these organics are divided into polyvinyl chloride (PVC), polymorphic waste, and lignocellulose. The interaction mechanism and chloride release characteristics of PVC with llulose, xylan, and lignin, the three components of lignocellulose, were examined in the co-pyrolysis process. The results show that the PVC and the three components synergize positively in the de-hydrogen chloride stage. The PVC can accelerate the pyrolysis of the three components. Cl is mainly released as HCl, CH₃Cl, and chlorobenzene during the co-pyrolysis process. In the co-pyrolysis process of PVC and cellulose, HCl acts as an acidic catalyst to promote the formation of more aromatic hydrocarbons. During the co-pyrolysis of PVC and xylan the acetic acid produced by xylan reduces the starting temperature of HCl release by about 25–30 ℃. Compared with cellulose and xylan, lignin has the greatest inhibitory effect on HCl release. Lignin enhances the chemical bond C–Cl breakage in PVC, reducing HCl but promoting the release of CH₃Cl. In short, the three-component promotes the thermal cracking reaction of PVC, reduces the activation energy of the response in the de-hydrogen chloride stage, and produces more chloride. The average activation energies of pyrolysis of PVC with the mixture of three-component are reduced by 25.88%–48.73%, 36.46%–43.73%, and 44.88%–72.83%, respectively.