Teijin Chemical Co., Ltd. has developed a new process that can fully recycle polycarbonate (PC) resin. This process adopts new purification technology to recover and recycle high-purity bisphenol A. With this new technology, it is expected that it can be made from pure monomer. The energy required to make bisphenol A is reduced by 66%.
Teijin employs a process in which the PC is placed in strong alkali, decomposed at normal pressure and at a temperature of 40-50°C. Under this condition, the reaction does not generate by-products, so the product monomer is suitable for preparing bisphenol A with a purity of 99.9% and can be used directly for the production of PC. The key innovation of this technology is the proprietary liquid phase purification process, which can greatly save operating costs compared to distillation. The total recovery of bisphenol A can exceed 95%.
Teijin Chemical Co., Ltd. built a medium-sized plant at the Matsuyama Plant in Japan to dispose of 500 to 1,000 tons/year of waste PC resin. The plant was put into operation in February 2005. The company decided to introduce the process to industrial applications in 2006. .
