Catalytic recycling of the mixture of polypropylene and polystyrene

Catalytic degradation of the mixture of polypropylene (PP) and polystyrene (PS) was investigated in a semi-batch reactor. For all the catalysts HNZ, SA, HZSM-5) tested, the main degradation products were liquid oils with gasoline range carbon number distributions. A natural clinoptilolite zeolite (HNZ) showed as good catalytic performance as silica-alumina (SA). HZSM-5 catalyst produced the highest amount of gaseous products. Increase of degradation temperature resulted in a decrease of ethylbenzene and propylbenzene, but an increase of styrene. Thermogravimetric analysis revealed the interaction of PP and PS in the catalytic degradation. (C) 2002 Elsevier Science Ltd, All rights reserved.