Pre-treatment of sewage sludge with Fenton’s peroxidation for the analysis of microplastics by analytical pyrolysis

Microplastic contamination has emerged as a major global environmental issue. Since this is a global problem of which there is still no accurate quantitative and qualitative knowledge, it is necessary to develop tools for sampling, analysis and modelling of the distribution of these micropollutants. Small plastic particles are now pervasive across marine and freshwater systems. Recently, attention is beginning to focus on the occurrence of microplastics within other environmental compartments such as sewage sludge because have been shown to have a high trapping efficiency for microplastics. However, methods for extracting plastic particles have not yet been systemically tested or standardized. This study investigated a protocol for the removal of organic material during analysis of microplastics from sewage sludge: Fenton’s peroxidation. Attention was paid on the detection and quantification of some of the commercial polymers such as PE, PP, PET, PA6, PC, PS and PVC by Py-GC-MS. The thermoanalytical Py- GC/MS technique can provide qualitative and quantitative information about the microplastics more accurate than already applied optical techniques. In this work, an identification of a methodological approach for the optimization of the Fenton reaction supported by a Design of Experiment was performed, to best interpret the effect of numerous variables of this reaction. The reduction of organic matter was evaluated through the determination of the total organic carbon (TOC) analysis.