Characterization of the Non-Polymeric Fraction of Post-Consumer LCD Monitor Housings

Abstract

This work aims to characterize the non-polymeric components, usually present as additives to perform different functions, present in the polymer housing of post-consumer computer monitors, in order to help finding the most adequate recycling destination for such material. The non-polymeric fraction was characterized by thermogravimetry (TG), loss on ignition (LOI), chemical analysis by X-ray fluorescence (XRF), and atomic absorption spectroscopy, scanning electron microscopy with energy dispersive spectroscopy (SEM/EDS), and X-ray diffraction (XRD). TG analysis indicated that the polymer has about 4 wt% of inorganic materials (performed in N2 atmosphere), whereas LOI (performed in ambient atmosphere) indicated just 0.07 wt%. The XRF, SEM/EDS analyses, and atomic absorption spectroscopy of the post-fired material confirmed the presence of many elements. Nonetheless, toxicological relevant elements showed acceptable concentration levels, below 0.01 ppm. The XRD analysis indicated the presence of crystalline phases based on CaCO3, SiO2 and TiO2.