Milestone Reached for Total Recycling System for Plastic PET Bottles

The National Institute of Advanced Industrial Science and Technology (AIST) has succeeded in decomposing plastic chips, such from as PET (polyethylene terephthalate) bottles, into raw materials by heating them with water at high temperatures, it was announced at an academic conference held by the Japan Petroleum Institute in Tokyo on May 19, 2006.

The method newly developed by the catalysts team at AIST's Research Center for Compact Chemical Processes involves heating polyester resin with water at up to 300 degrees Celsius in a sealed stainless reaction container, to decompose it into terephthalic acid and ethylene glycol. The team has also found it possible to attain the same result at 275 degrees C by adding terephthalic acid before heating.

Most conventional methods for recycling PET bottles involve grinding and melting the material into regenerated resin, which is then used as fiber for clothing or sheets. A method also exists to chemically decompose PET bottles into raw materials, although this method results in toxic waste discharge due to the use of substances such as methanol.

The new method is not only environmentally friendly but also economical, as exhaust heat can be utilized if the depolymerization units are integrated with waste treatment facilities. In order to put the new method into practice, AIST is continuing research into a total recycling system that includes the conventional plastic bottle collection system.

http://unit.aist.go.jp/tohoku/index-e.html

Posted: 2006/08/02 10:33:09 AM
Japanese version