CHEMICAL RECOVERY FROM POLYSTYRENE WASTE AND LOW DENSITY POLYETHYLENE VIA CONVENTIONAL PYROLYSIS

Abstract

In Turkey, plastic wastes have formed 5-14 % of total solid wastes. Plastic wastes have been classified as thermoplastic and thermosets. Thermoplastic wastes which covers Polyethylene (PE), Polystyrene (PS), Polypropylene (PP), Polyethylene terephthalate (PET) and Polyvinyl chloride (PVC) can be recycled by using mechanical recycling, energy recovery and chemical recovery routes. Pyrolysis as a chemical recovery technique is important to produce invaluable chemicals in high yields. In this study, it was aimed to obtain hydrocarbons from PS and Low density Polyethylene (LDPE) via pyrolysis. Product yields were calculated and liquid products were analyzed via GC-MS. In the light of the results, it was deduced that 520 ⁰C and 570 ⁰C were the suitable temperatures to obtain the liquid product with maximum yields for LDPE and PS respectively. That temperature was found for LDPE and PS co-pyrolysis as 570 ⁰C. It was determined that Benzene-Toluene-Ethyl Benzene (BTE) fraction amount increased from 5 % to 30 % with LDPE adding in the feed for almost same liquid product yields of PS (88%) and LDPE/PS (84 %). In addition, it was obtained the pyrolytic liquid which comprised of wholly alkanes and alkenes for LDPE with 70 % product yield.