Thermal Pyrolysis of Waste Disposable Plastic Syringes and Pyrolysis Thermodynamics


Koç A.

Advances in Chemical Engineering and Science, cilt.12, sa.2, ss.96-113, 2022 (Hakemli Dergi)

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 12 Sayı: 2
  • Basım Tarihi: 2022
  • Dergi Adı: Advances in Chemical Engineering and Science
  • Derginin Tarandığı İndeksler: Applied Science & Technology Source
  • Sayfa Sayıları: ss.96-113
  • İnönü Üniversitesi Adresli: Evet

Özet

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, Eact, and thermodynamic quantities such as reaction enthalpy, ∆H, reaction entropy, ∆Sve and Gibbs free energy, ∆Gwere calculated. In the thermal pyrolysis of PP and HDPE plastic wastes, Eact, ∆H, ∆G, ∆Svalues 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.