Jan 01, 2019 · Low quality PET bottle, colored or contaminated bottle, can be recycled through a chemical break down of the PET into its monomers, purification of the monomers and conversion into new PET. PET can be depolymerized on various ways to yield monomers such as TPA, DMT, and bis-2-hydroxyethyl terephthalate (BHET) for the production of fresh polyester.