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

造成严重污染问题的日益增多的废塑料是一种廉价而丰富的化学品和能源来源。化学回收方法，将废塑料转化为有用的碳氢化合物，如汽油，被认为是一种有用的方法。具有代表性的废塑料有聚烯烃、聚苯乙烯（PS）、聚对苯二甲酸乙二醇酯（PET）和聚氯乙烯（PVC）。这项工作的主要目的是从这些废塑料中回收有用的碳氢化合物。PS可以很容易地回收，而从其他塑料中回收高产量的有价值的化学物质是困难的。因此，我们研究了剩余塑料的化学回收，得到以下结果：1。PET在蒸汽气氛下成功降解为单体，无碳质残留。此外，利用氧化铁催化剂，生产的对苯二甲酸可转化为苯和甲苯。PVC在573 ~ 653 K的温度范围内，在氮气或蒸汽气氛中完全脱氯。聚乙烯（PE）是聚烯烃的一种，在773 K.4以上可降解。研制了一种用于废塑料分解的滴流床式反应器。这个反应器使熔化的塑料和载气之间有良好的接触。新研制的镍负载稀土金属交换y型沸石（Ni/REY）可在蒸汽气氛下裂解塑料分解产生的重油，生产高品质汽油。

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.