Expanded polystyrene (EPS) and waste cooking oil (WCO): from urban wastes to potential material of construction

Abstract

This study addresses the degassing of expanded polystyrene (EPS) using waste cooking oil (WCO) to produce a recycled EPS with potential use as construction material. Morphological, chemical and mechanical tests were performed. Scanning electron microscopy was used to assess the recycled EPS surface and its relationship with the precursors. The micrographs presented a similar surface appearance to EPS; however, some heterogeneity was observed due to variations in the composition of the material. Spectra from the chemical characterization showed similar compositions originating from EPS and WCO, suggesting a mixed process between precursors without a chemical reaction between them. An absorption band at 2930 cm-1 was found in both EPS and recycled EPS, indicating the presence of a C–H aliphatic group. An absorption band at 752 cm-1 was found in the recycled EPS with WCO, indicating the presence of a substituted aromatic ring, which suggests a mixture of precursors at high temperature (165 C) without further chemical reactions to produce a new material. The results obtained from mechanical tests were tensile strength: 16.13 ± 1.07 MPa, elongation modulus: 1798.388 MPa, flexural modulus: 1797.1899 MPa and compression strength: 18.10 ± 2.89 MPa.