Abstract: Causing environmental pollution easily, wasted expanded polystyrene (EPS) should be fully used. Using cracking-method to recycle EPS usually has two problems. One is how to avoid catalyst-poisoning, the other is how to deal with remnants. So cinder was used as catalyst for recycling EPS in this paper. The cracking products of EPS were analyzed by Gas Chromatography. The results showed that: The speed of elevating temperature and the cracking temperature had certain influence on the yield of styrene. Elevating of temperature slowly at 380℃, the content of styrene in liquid products was the highest ( 63%). Compared with other catalysts, the cinder-catalyzed yield of cracking products was higher. Under atmospheric pressure, when the amount of catalyst was over 8%, the yield (89%) of liquid products no longer increased. As waste from coal-fired equipment, cinder has the characteristics of light quality and large ratio surface area. The main chemical components of cinder were SiO2, Al2O3, Fe2O3 and CaO. Using wasted cinder as catalyst had no waste of resources due to catalyst-poisoning. After simple processing, the cracking residues can be reused as roadbed through-hole materials.

Key words: Cinder, Catalyst, Polystyrene foam, Cracking, Waste recycling