IONIQA's PET depolymerisation story: from bottles to Multi-Layer Trays and beyond

Current environmental needs make developments in the field of plastic recycling increasingly urgent, as plastics consumption keeps increasing while governmentally set recycling targets are far out of reach. Impurities containing plastic waste needs to be fed to recycling processes, which in their turn require to produce virgin quality like materials as output. Feedstock impurities can be of any kind; either as part of the composition of the feed due to sorting efficiencies or as high- or low molecular weight additives and degradation products. These impurities in the feedstock make traditional mechanical recycling only applicable to a certain percentage of the plastic waste flakes available on the market. Chemical recycling can be a solution to this challenge as it can handle higher impurity levels in waste plastic flake feedstocks. This opens opportunities for recycling of feedstocks such as sorter reject streams, polyethylene terephthalate (PET) fines and multi-layer tray waste. Ioniqa’s glycolysis technology breaks down PET into monomers, which makes it much easier to remove impurities compared to isolating impurities from mixtures containing oligomers. In the PET glycolysis process, the ester bonds in PET are cleaved by mono ethylene glycol (MEG) to form Bis(2-Hydroxyethyl) terephthalate (BHET). BHET is a monomer known in the PET-industry, as it is an intermediate in today’s PET polymerisation processes that utilize oil based raw materials. The glycolysis process is typically performed at temperatures around the boiling point of MEG and in the presence of a catalyst. The four main steps that can be distinguished in the Ioniqa process are: reaction, inert and catalyst separation, purification and product isolation. Multi-layer trays add one more challenge due to the presence of other polymers in packaging, which Ioniqa’s technology aims to remove prior to its core process.