Influence of temperature and reaction time on the conversion of polystyrene waste to pyrolysis liquid oil

Waste Manag. 2016 Dec:58:250-259. doi: 10.1016/j.wasman.2016.09.023. Epub 2016 Oct 4.

Abstract

This paper aims to investigate the effect of temperature and reaction time on the yield and quality of liquid oil produced from a pyrolysis process. Polystyrene (PS) type plastic waste was used as a feedstock in a small pilot scale batch pyrolysis reactor. At 400°C with a reaction time of 75min, the gas yield was 8% by mass, the char yield was 16% by mass, while the liquid oil yield was 76% by mass. Raising the temperature to 450°C increased the gas production to 13% by mass, reduced the char production to 6.2% and increased the liquid oil yield to 80.8% by mass. The optimum temperature and reaction time was found to be 450°C and 75min. The liquid oil at optimum conditions had a dynamic viscosity of 1.77mPas, kinematic viscosity of 1.92cSt, a density of 0.92g/cm3, a pour point of -60°C, a freezing point of -64°C, a flash point of 30.2°C and a high heating value (HHV) of 41.6MJ/kg this is similar to conventional diesel. The gas chromatography with mass spectrophotometry (GC-MS) analysis showed that liquid oil contains mainly styrene (48%), toluene (26%) and ethyl-benzene (21%) compounds.

Keywords: Batch pyrolysis reactor; Liquid oil; Municipal plastic waste; Polystyrene (PS) plastic; Pyrolysis.

MeSH terms

  • Equipment Design
  • Gas Chromatography-Mass Spectrometry
  • Pilot Projects
  • Polystyrenes / chemistry*
  • Reaction Time
  • Refuse Disposal / instrumentation
  • Refuse Disposal / methods*
  • Saudi Arabia
  • Solid Waste
  • Temperature
  • Viscosity

Substances

  • Polystyrenes
  • Solid Waste