Evaluating the Potential and Technical Criteria for Recycling Coated Packaging Papers

Abstract

The recyclability of coated papers or paperboards used for food packaging is an important criterion in the transition towards a circular economy. In line with current European legislation, packaging materials need to be recyclable for up to 65 % (2025) or 70 % (2030), while full re-use, recyclability, or biodegradability of packaging paper is requested at national level (2025). However, the presence of barrier coatings on food packaging papers interferes with the repulping of paper fibers, causing degradation of the recycled paper quality. In this work, general criteria for recyclability and requirements of packaging paper products are considered, i.e. potential for sticky removal and fragmentation behaviour of the fibers. Therefore, several procedures to assess the repulpability at laboratory scale are reviewed and critical parameters in the repulping process are determined. In particular, a comparative study between recently proposed harmonized test methods (e.g., CEPI) is presented in order to validate the representativity of lab-scale results, including repulping, collection of rejects and screening of different fiber lengths. Based on repulping studies for a selection of commercially available packaging papers, different results for both laminated and dispersion-coated papers will be presented. Finally, the effects of coating composition and/or presence of specific additives or interlayers on the repulping will be discussed. In particular, the dispersion coatings with biopolymers offer favourable recyclability and the presence of nanocellulose fillers may enhance the quality of the recycled pulp fibers.