Open AccessDetailed Analysis of the Composition of Selected Plastic Packaging Waste Products and Its Implications for Mechanical and Thermochemical Recycling
Author(s) -
Martijn Roosen,
Nicolas Mys,
Marvin Kusenberg,
Pieter Billen,
Ann Dumoulin,
Jo Dewulf,
Kevin Van Geem,
Kim Ragaert,
Steven De Meester
Publication year - 2020
Publication title -
environmental science and technology
Language(s) - English
Resource type - Journals
eISSN - 1520-5851
pISSN - 0013-936X
DOI - 10.1021/acs.est.0c03371
Subject(s) - polymer , elemental analysis , differential scanning calorimetry , bottle , halogen , food packaging , inductively coupled plasma , plastic packaging , impurity , fourier transform infrared spectroscopy , materials science , chemistry , chemical engineering , waste management , organic chemistry , composite material , engineering , physics , alkyl , food science , plasma , quantum mechanics , thermodynamics
Plastic packaging typically consists of a mixture of polymers and contains a whole range of components, such as paper, organic residue, halogens, and metals, which pose problems during recycling. Nevertheless, until today, limited detailed data are available on the full polymer composition of plastic packaging waste taking into account the separable packaging parts present in a certain waste stream, nor on their quantitative levels of (elemental) impurities. This paper therefore presents an unprecedented in-depth analysis of the polymer and elemental composition, including C, H, N, S, O, metals, and halogens, of commonly generated plastic packaging waste streams in European sorting facilities. Various analytical techniques are applied, including Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), polarized optical microscopy, ion chromatography, and inductively coupled plasma optical emission spectrometry (ICP-OES), on more than 100 different plastic packaging products, which are all separated into their different packaging subcomponents (e.g., a bottle into the bottle itself, the cap, and the label). Our results show that certain waste streams consist of mixtures of up to nine different polymers and contain various elements of the periodic table, in particular metals such as Ca, Al, Na, Zn, and Fe and halogens like Cl and F, occurring in concentrations between 1 and 3000 ppm. As discussed in the paper, both polymer and elemental impurities impede in many cases closed-loop recycling and require advanced pretreatment steps, increasing the overall recycling cost.