Removable Identification Technology to Differentiate Food Contact PET in Mixed Waste Streams: Interim Report

The equivalent of 66 billion 1.5 L poly(ethylene terephthalate) (PET) bottles were collected and recycled in 2014, representing 57% of bottles and containers placed in the market in Europe (based on a Petcore Europe study). The EC-funded ""Polymark"" project brings together stakeholders from across the PET value chain with the common aim of increasing the availability of ""closed-loop"" recycled PET (from used bottle to new bottle) by improving identification and separation of food contact approved PET from mixed waste streams. This interim report outlines the successful development of a prototype, flexible, coating-based approach for marking PET bottles, detailing the combination of suitable food-contact approved fluorescent markers and alkali-strippable polymeric matrices used. Removal of the marker is demonstrated so that post-recycling marker accumulation and associated potential for false positive detection in the long term is minimised. Detector technology suitable for high speed sorting was developed in parallel to marking technology and initial results in this area are also reported.