The Kinetic Studies of Elimination of HCl During Thermal Decomposition of PVC in the Presence of Transition Metal Oxides

: The effects of nine kinds of transition metal oxides on the elimination kinetics of hydrogen chloride (HCl) during thermal decomposition of polyvinyl chloride (PVC) at 210°C were investigated using online measurement of conductivity. It was found that the presence of TiO2, V2O5, Cr2O3, and MoO3 obviously decreases the elimination rate of HCl and the amount of HCl released by a factor of 10–20 times, indicating that they have a strong inhibiting effect on the release of HCl. The presence of MnO2, ZnO, CuO, Co2O3, and Fe2O3 promotes the elimination of HCl during thermal decomposition of PVC. The maximum elimination rate of HCl in PVC/ZnO, especially, is ca. 10 times as high as that of PVC. In this work, the LnLn kinetic model, Ln(1 − α) = − ktn, describes the kinetics of elimination of HCl during thermal decomposition of PVC. The elimination rate of HCl during thermal decomposition of PVC increases with the rise of the apparent order of reaction, n, in this model n value well describes the elimination kinetics of HCl during thermal decomposition of PVC.