Literature Review on the Feasibility of Recycling Electrical and Electronic Waste (WEEE)

Abstract

The growing amount of waste electrical and electronic equipment (WEEE) is a global problem, with generation increasing five times faster than documented recycling. In 2022, 62 million tons of e-waste were produced, but less than 22.3% was collected and recycled properly. The aim of the work was to analyze the main polymers in WEEE, discuss the challenges of recycling and characterizing them, and explore the feasibility of applying them in the production of filaments for 3D printing. The methodology consisted of a qualitative analysis of 8 scientific articles selected from the Scopus and Web of Science databases. The research was limited to publications in English between 2003 and 2025. The results highlight the importance of characterization for recycling. Techniques such as FTIR, TGA and DSC are essential for understanding the chemical, thermal and mechanical properties of polymers. FTIR identifies compounds such as hydrocarbons and aromatic rings and is useful for unknown polymers. TGA measures the loss or gain of mass with temperature, indicating thermal degradation. DSC identifies changes in physical state, such as melting temperature (Tm), glass transition temperature (Tg) and crystallization temperature (Tc). Two recycling techniques are promising: chemical and mechanical. Chemical recycling, via pyrolysis, can convert plastics into useful monomers or fractions. However, plastics with brominated flame retardants (BFRs) can generate toxic substances. Pre-treatment methods, such as the CreaSolv® process, have proven effective in removing BFRs. Mechanical recycling faces challenges such as property degradation and material heterogeneity. Additive manufacturing (AM), especially FDM/FFF technology, is an alternative for reusing WEEE plastics and adding value. However, the variability of equipment shapes and sizes makes process automation complex.