Method development for fast classification of waste plastic multilayer polyolefin films using near-infrared (NIR) handheld spectrometer

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

The amount of packaging waste in the EU is constantly increasing, including rising percentages of multilayer films in packaging waste. Two-thirds of all post-consumer plastic waste are polyolefins, with a recycling rate of only 23 % in Europe. Further developments are required to achieve the EU´s plastic packaging targets from the Council directive 2008/98/EC of a 55% recycling rate by 2030. Chemical recycling is one of the most promising solutions to recycle polyolefin films. Chemical recycling requires high purity of input material. Therefore, it is necessary to develop a method for fast classification of input material. Near-infrared (NIR) handheld spectrometers are imposed to fulfil the requirements. NIR handheld spectrometers have been proven to classify different monolayer plastic polymers successfully, but their suitability for multilayer materials has not yet been determined. The tests were run to demonstrate the prospect of utilizing a NIR handheld spectrometer to classify polyolefin multilayer films and separate them from non-polyolefin multilayer films. The used samples consisted of four multilayer fractions PP-PE, PET-PE, PA-PE and PET-PP. They were then separated into a polyolefin fraction (PP-PE) and a non-polyolefin fraction (PET-PE, PA-PE and PET-PP). Acquired spectra had to go through signal pre-treatment before being further processed using chemometric tools like PCA and KNN Analysis, resulting in a complete classification of two fractions. Results show promising outcomes for classifying polyolefin multilayer waste films as a control of input material for chemical recycling using NIR handheld spectrometers.

Details

Original languageEnglish
Title of host publicationCHANIA 2023 10th International Conference on Sustainable Solid Waste Management
Publication statusPublished - Jun 2023