VOC EMISSIONS FROM WASTE PLASTICS DURING MELTING PROCESSES

Hazardous compounds emitted during the plastic melting process were analyzed to indicate potentialair pollution issues associated with recycle plants for waste plastics. These hazardous compoundsmight be not only from polymer degradation but also from additives and print ink. To confirm what areemitted from them, melting experiments were conducted (150, 200 and 250C, in air or N2) and volatileorganic compounds (VOCs) emitted from samples were trapped by Tenax/Carboxen adsorption tubesand analyzed by TD-GC/MS. In the present study, virgin polymers such as low-density polyethylene(LDPE), polypropylene (PP), polystyrene (PS) and reproduced plastic were tested. As a result, highertemperature caused more emission of VOCs. Moreover, less VOCs and less oxygenated organiccompounds which were said to be hazardous to human and the cause of bad odor were emitted in N2atmosphere than in air. Based on these results, lower temperature and lower oxygen level arepreferable to reduce hazardous compounds during the plastic melting process of mechanical recycling.