(562bj) Sustainable Strategies to Recycle Waste Electrical and Electronic Plastics by Thermochemical Processes

Electronic waste disposal and recycle are becoming a global concern as the generation of e-waste increases exponentially with time. An amount of 44.7 million metric tonnes (Mt) of e-waste was generated globally in the year 2016 and only 20% (8.9 million metric tonnes) was recycled. The presence of recoverable components, such as valuable metals (gold, silver and copper) and non-metallic fractions (plastics), makes the e-waste recycling an economically viable recycling industry particularly in the developing countries. However, e-waste contains serious toxic substances such as brominated fire retardants, heavy metals etc. [1]. These hazardous substances are responsible for the serious health issues to the people associated with the e-waste recycling and also causes pollution to the environment. Therefore, it is significant to develop sustainable technologies those can separate the toxic content and recover the valuable materials from e-waste. A significant portion of electronic waste consists of the non-metallic fractions, as most of the outer body of the small and large electronic and electrical equipment’s are made from plastics[1]. A substantial amount of plastics also present in the waste printed circuit boards. The current study focusses on the development of a thermochemical process to recover toxic free plastics, polymer or the plastics derived fuel/chemicals in the most efficient manner. Solvent extraction process [2] has been used to remove trace metals and BFRs and subsequently thermochemical processes[3] such as pyrolysis will be used to recover toxic free chemicals and fuels from the e-waste plastics.

References

[1] E. Dimitrakakis, A. Janz, B. Bilitewski, and E. Gidarakos, "Small WEEE: Determining recyclables and hazardous substances in plastics," Journal of Hazardous Materials, vol. 161, no. 2, pp. 913-919, 2009/01/30/ 2009.

[2] X. Zhao, L. Zhan, B. Xie, and B. Gao, "Products derived from waste plastics (PC, HIPS, ABS, PP and PA6) via hydrothermal treatment: Characterization and potential applications," Chemosphere, vol. 207, pp. 742-752, Sep 2018.

[3] Y. Shen, X. Chen, X. Ge, and M. Chen, "Thermochemical treatment of non-metallic residues from waste printed circuit board: Pyrolysis vs. combustion," Journal of Cleaner Production, vol. 176, pp. 1045-1053, 2018/03/01/ 2018.