Recovery of Chemicals and Gasoline-Range Fuels from Plastic Wastes via Pyrolysis

The aim of the present study is to describe non-catalytic pyrolysis of plastic waste materials and to determine yields of pyrolysis products. The waste plastics of polystyrene (PS), polyethylene (PE), and polypropylene (PP) were pyrolyzed in this study. Pyrolysis appears to be a technique that is able to reduce a bulky, high polluting industrial waste while producing energy and/or valuable chemical compounds. The pyrolysis of plastic wastes produces a whole spectrum of hydrocarbons including paraffins, olefins, naphthalenes and aromatics. The total yields of paraffins and olefins of PE and PP wastes obtained by pyrolysis were higher than that of PS. The yields of paraffins from plastic wastes decrease from 34.4 to 27.7% with increasing pyrolysis temperature from 625 to 800 K, and then slightly increase with temperature increasing from 825 to 875 K. The yields of olefins decrease from 41.3 to 32.4 with increasing pyrolysis temperature from 625 to 875 K. The yields of naphthalenes increase from 19.5 to 22.7% with increasing pyrolysis temperature from 625 to 875 K. The yields of aromatics increase from 3.2 to 11.5% with increasing pyrolysis temperature from 625 to 875.