Metal recovery in mobile phone waste: Characterization of metal composition and economic assessment through shredding and screening processes

Abstract

Recycling mobile phones, including their batteries, has become crucial for environmental sustainability, but traditional manual dismantling methods are time-consuming and inefficient. This study aims to improve the pre-processing of end-of-life mobile phones (EoL-MPs) through industrial shredding and sieving, minimizing manual labor. For the first time, a sample of 850 mobile phones in an interval of 20 years (2000–2020) was collected and analyzed before and after being processed. EoL-MP main bodies and batteries were crushed and sieved into eight distinct size fractions. This study examined 14 metals, including aluminum (Al), copper (Cu), iron (Fe), zinc (Zn), nickel (Ni), manganese (Mn), chromium (Cr), cobalt (Co), lithium (Li), gold (Au), silver (Ag), neodymium (Nd), platinum (Pt), and palladium (Pd). The results show that 1 kg of mobile phone bodies contains approximately 278 g of metals, valued at $13.41, with $10.97 derived from Au. The metal distribution revealed that larger fractions (>2 mm) are rich in structural metals such as Fe and Al. The finest fraction (<0.125 mm) contained up to 435 mg/kg of Au, with enrichment factors reaching 3 to 5 for Au, Pa, and Pt. Batteries showed even higher concentrations, with 524 g of metals per kilogram, valued at $11.37/kg, predominantly from Co and Au. Co was concentrated in smaller fractions, reaching 331 g/kg in particles smaller than 1.25 mm. The study provides key insights into efficient metal recovery strategies, emphasizing the economic and environmental potential of recycling mobile phone waste. The findings highlight the importance of optimizing pre-processing methods to achieve the growing demand for sustainable waste management solutions.