CONVERSION OF MIXTURES OF PYROLYSIS FEEDS TOCKS AND THERMOCHEMICAL PRETREATED PLASTIC REWASTES - AN ALTERNATIVE OF RAW-MATERIAL PLASTICS RECYCLING

The utilization of pre-treated polyolefin rewastes with high-boiling h ydrocarbon fractions was investigated as alternative of raw material r ecycling. Pyrolysis of selected mixtures into lower olefins and olefin ic intermediates has been performed in a flow reactor in the presence of steam (or inert gas) as diluent. The effect of feed composition, re sidence time (0.3-1.23), and temperatures (580--820 degrees C) on prod uct yields was studied. The addition of pre-treated plastics in specif ic percentages (up to 15 wt-%) does not lead to any significant change s in the yields. Coke formation on metal surfaces during the thermal c onversion of the various hydrocarbon mixtures was additionally studied using a gravimetric micro-balance. An effect of feed composition on t he coke amount could not been observed.