Pellenc ST and Ampacet, respectively global leaders in sensor-based sorting solutions and Masterbatch solutions, collaborated on sorting studies to optimize the recyclability of dark PET packaging on existing recycling lines. Since 2021, COTREP has published a test protocol assessing dark packaging detectability in optical sorting. COTREP is a Technical Committee for the recyclability of household Plastic Packaging in France joining forces with Citeo, Elipso, SRP and Valorplast.
Standard black polyethylene terephthalate (PET) packaging poses several challenges for the recycling value chain.
Plastics recycling starts with the sorting of mixed plastic wastes into separate mono-material streams (e.g. PET, PE, PP, PS…) at material recovery facilities (MRFs). These facilities use near-infrared (NIR) technology to recognize the resin type used in plastic articles. The key limitation to near infrared optical sorting is its inability to identify and separate plastics that contain carbon black, the most commonly used black pigment. Carbon black absorbs the most part of the infrared spectrum, preventing the backscattering of infrared light to the NIR spectrometer and consequently blocking the recognition of the resin’s fingerprint. Such mixed plastic packaging ends in a residual fraction, which is not recycled but disposed mainly via incineration.
Ampacet has developed alternative black masterbatch solutions promoted under the REC-NIR-BLACK brand. Being near-infrared (NIR) transparent, packaging made with REC-NIR-BLACK can be sorted using conventional NIR optical technologies and effectively recycled thus participating in the Circular Economy.
