Recovery of Oil and Monomer from Waste Plastics by Pyrolytic Treatment

초록

The liquefaction of waste plastics by pyrolytic treatment in the staged reactor has been studied to investigate the recovery of oil and monomer. The pyrolysis experiments were focused on obtaining high yield of oil and monomer. To reduce pyrolytic time, waste plastics are pyrolysed in waste motor oil. Oil yield from polystyrene was shown to approximate 94wt%. But in the case of polypropylene and polyethylene, oil yield was dependent on the type of catalyst added and a lot of amount of wax was formed by thermal degradation without catalysts. The fraction of styrene monomer in the pyrolytic oil of polystyrene was 75 - 79 wt% when BaO catalysts were used. Only 18 wt% of styrene monomer yield was obtained by pyrolysing this plastic at 500℃ without catalysts. Yields of styrene monomer produced over silica, alumina and activated carbon catalyst were 40wt%, 67wt% and 29wt% respectively. The influence of catalyst acidity and basicity on the recovery of styrene monomer was investigated over different catalysts.