Evaluation of the recycling potential of obsolete mobile phones through secondary material resources identification: A comprehensive characterization study

Abstract

The growing concern over the management of e-wastes has generated an interest in the recovery of resources from these wastes under the concept of urban mining and circular economy. However, in the absence of accurate knowledge of the physico-chemical compositional structure of these wastes makes the recycling process difficult. Thus, the present study conducted a recycling-oriented characterization of waste mobile phones (WMPs) for the identification of secondary materials and estimated their recycling potential. The characterization was performed using ICP-OES and FTIR techniques after dismantling WMPs for the determination of elemental composition and the polymeric fractions respectively. Dismantling of the WMPs revealed that enclosures, batteries, display modules, and PCBs consist of 35.33 wt%, 28.9 wt%, 19.44 wt%, and 16.31 wt% respectively. Of these components, PCBs constitute the highest economic recovery potential with an estimated potential revenue generation of more than 50,000 US $ per ton of waste PCBs. Copper showed the highest recovery potential (234.39 tons/year) with an economic value of approximately 3317 US $/ton of WPCBs followed by Sn (27.37 tons/year) and Ni (24.64 tons/year). Among different precious metals, Au was found to have the highest percentage of economic value (76.22%) followed by Pd (8.16%) and Ag (3.13%). The display modules and enclosures were found to have relatively lower contributions than WPCBs in the overall recycling potential due to lower metal contents and mixed polymeric fractions. The findings in the study indicate that WMPs could serve as a promising new source for sustainable secondary mining of rare and valuable metals. Further, the study will help the policymakers in designing effective e-waste management strategies through the promotion of sustainable recovery of materials.