Thermal Pyrolysis of Waste Disposable Plastic Syringes and Pyrolysis Thermodynamics  

作　　者：Adil Koç Adil Koç(Department of Chemical Engineering, Faculty of Engineering, University of İnönü, Malatya, Turkey)

机构地区：[1]Department of Chemical Engineering, Faculty of Engineering, University of İ nö nü, Malatya, Turkey

出　　处：《Advances in Chemical Engineering and Science》2022年第2期96-113,共18页化学工程与科学期刊（英文）

摘　　要：In this study, the convertibility of disposable plastic waste injectors made of HDPE and PP plastics into valuable chemical products by thermal pyrolysis was investigated. While PP plastic wastes were decomposed in the temperature range of 400°C - 445°C, HDPE plastic wastes were decomposed in the higher temperature range (430°C - 475°C). Although the physical appearance of the liquid products obtained in the thermal decomposition of PP plastic wastes are lighter in color and fluid, it has been observed that the liquid decomposition products of HDPE plastic wastes have a more dense and viscous structure. By using the first-order kinetic model, kinetic expressions for both plastic wastes were derived, reaction rate constants, k, and activation energy, E_act, and thermodynamic quantities such as reaction enthalpy, △H^≠, reaction entropy, △S^≠ ve and Gibbs free energy, △G^≠ were calculated. In the thermal pyrolysis of PP and HDPE plastic wastes, E_act, △H^≠, △G^≠, △S^≠ values are 162.30 kJ/mol, 156.52 kJ/mol, 219.50 kJ/mol, -87.71 J/molK, and 201.80 kJ/mol, 195.77 kJ/mol, and 229.14 kJ/mol, -46.48 J/molK, respectively. These thermodynamic quantities calculated for both plastic wastes show that the pyrolytic decomposition studies carried out in an inert gas atmosphere have endothermic reaction behavior.In this study, the convertibility of disposable plastic waste injectors made of HDPE and PP plastics into valuable chemical products by thermal pyrolysis was investigated. While PP plastic wastes were decomposed in the temperature range of 400°C - 445°C, HDPE plastic wastes were decomposed in the higher temperature range (430°C - 475°C). Although the physical appearance of the liquid products obtained in the thermal decomposition of PP plastic wastes are lighter in color and fluid, it has been observed that the liquid decomposition products of HDPE plastic wastes have a more dense and viscous structure. By using the first-order kinetic model, kinetic expressions for both plastic wastes were derived, reaction rate constants, k, and activation energy, E_act, and thermodynamic quantities such as reaction enthalpy, △H^≠, reaction entropy, △S^≠ ve and Gibbs free energy, △G^≠ were calculated. In the thermal pyrolysis of PP and HDPE plastic wastes, E_act, △H^≠, △G^≠, △S^≠ values are 162.30 kJ/mol, 156.52 kJ/mol, 219.50 kJ/mol, -87.71 J/molK, and 201.80 kJ/mol, 195.77 kJ/mol, and 229.14 kJ/mol, -46.48 J/molK, respectively. These thermodynamic quantities calculated for both plastic wastes show that the pyrolytic decomposition studies carried out in an inert gas atmosphere have endothermic reaction behavior.

关 键 词：Plastic Waste Injector Rate Constant Thermodynamic Quantities 

分 类 号：TQ3[化学工程]