Development of Chemical Recycling Process for Post- Consumer PET Bottles by Methanolysis in Supercritical Methanol

Post-consumer PET (polyethylene terephthalate) bottles have been recycled into fiber and sheet products ever since the Containers and Packing Recycling Law came into effect in 1997. There has been a growing need, however, for a chemical recycling process. In this process, post-consumer PET bottles are recycled into monomers that can be used as feed stocks for the recycled production of PET bottles for beverages. It is believed that such a process would be much more suitable for a recycling-oriented society. Mitsubishi Heavy Industries, Ltd. (MHI) has been developing a chemical recycling process that uses supercritical methanol in order to depolymerize PET material into its constituent monomers within a short time. During the development stage, it was found that the chemical recycling process developed by MHI (Mitsubishi Process) can recover monomers with qualities that are equivalent to those of the original monomers produced from petroleum. The results of feasibility studies have also shown that the Mitsubishi process can be economically feasible.