PBT Recycling
PBT Recycling
(Polybutylene Terephthalate)
Polybutylene terephthalate is a semi-crystalline polyester used for door and window hardware, automobile luggage racks and body panels, headlight reflectors, and fiber optic cables. It is being used to replace PVC for cable sheathing, due to a combination of environmental pressures and outstanding electrical properties across a wide range of temperatures. PBT is also replacing metals (in conjunction with PC as an alloy/blend) for automotive body panels.
Based on the ethelene glycol (EG) depolymerization/methanol-ester exchange method first introduced approximately 30 years ago, and applying technology for the manufacture and refining of dimethyl terephthalate (DMT) employed over many years, a new process has been developed to effectively and economically remove foreign matter, and recover high-purity DMT equal to that obtained from petroleum, even when the processed material contains finishing agents and additives such as other polymers and dyes. Used PBT is crushed and washed, and depolymerized with EG. The EG depolymerization process depolymerizes the crushed product to a monomer (BHET - bishydroxyethyl terephthalate) in the presence of a small amount of catalyst. The unrefined BHET is separated, and transformed into unrefined DMT with an ester exchange reaction using methanol. The unrefined DMT is refined using recrystallization and distillation to produce DMT having a purity of 99.99% of that of DMT obtained from petroleum.
Heathland searches to recycle plastics, including PBT, in ways that are best suitable for people and environment. Recycling happens in-house and at partner companies in Europe and/or Asia. Since the market for plastic recycling is very international, often it is difficult to keep track of how and where scrap plastics are recycled. Heathland works with partners who are qualified, have sufficient certification, and have set quality standards for the circumstances in which plastic materials are processed. This way, the company can keep as much control as possible on the circumstances in which it’s plastics are recycled. If you are interested in this way of recycling, whether your company is a collector, manufacturer, servicer or end-user, please contact us for possibilities.