Development of Conversion Process of Waste Plastics to Gasoline by Chemical Recycling Method

点击翻译按钮获取中文摘要

Increasing amount of waste plastics which causes serious pollution problem is a cheap and abundant source of chemicals and energy. The chemical recycling method, which converts waste plastics to useful hydrocarbons, such as gasoline, was recognized as a useful approach. The representative waste plastics are polyolefin, polysyrene (PS), polyethylene terephthalate (PET) and polyvinyl chloride (PVC). The main objective of this work is to recover useful hydrocarbons from these waste plastics. PS can be easily recycled, whereas it is difficult to recover valuable chemicals of high yeild from other plastics. Hence, we researched the chemical recycling of the remaining plastics, and got the following results :1. PET was succeeded to be degraded to monomers in steam atmosphere without any carbonaceous residue. Furthermore, using iron oxide catalyst, produced terephthalic acid could be converted to benzene and toluene.2. PVC was completely dechlorinated in the temperature range of 573 to 653 K in each of nitrogen or steam atmosphere.3. Polyethylene (PE), which is one of polyolefins, could be degraded above 773 K.4. Trickle bed type reactor was developed for the decomposition of waste plastics. This reactor enables to achieve a good contact between melted plastics and carrier gas.5. Nickel supported rare-earth metal exchanged Y-type zeolite (Ni/REY) was newly developed, which could crack heavy oil produced by the decomposition of plastics, yielding high quality gasoline in steam atmosphere.