Towards Sustainable Gold Recovery from Integrated Circuits Waste: Life Cycle Assessment of a Combined Physic-Hydrometallurgical Process

Integrated circuits (ICs) represent a promising secondary source of gold (Au) due to its high metal content. However, Au recovery from ICs remains challenging [1]. This study proposes a combined physico-hydrometallurgical process for Au recovery from ICs and evaluates its environmental performance through life cycle assessment (LCA) .The process combines a three-step physical pretreatment to enhance Au exposure and concentrate base metals. Non-magnetic sample passed through a leaching and purification process using ion-exchange resin increasing Au purity up to 86%. Then, the LCA of the process was conducted in SimaPro 10.2.0.1 with Ecoinvent 3.11.LCA of the developed process versus the six mining strategies showed the least impact in half of the environmental impact categories, making it the greenest strategy. This accomplishment is due to the energy matrix produced in Portugal and the high effort put into optimizing process. The Portuguese energy matrix based mostly renewable energy and not in oil (like Peru or Chile) nor nuclear energy like Sweden. LCA shows that the hybrid process is environmental competitive and, for several categories, substantially superior to primary Au extraction routes. The results reinforce the potential of the developed process as a sustainable alternative for Au recovery from ICs, contributing to the transition toward circular and low-impact resource recovery .

References

[1] Li, Kuo., Zhang, L., Xu, Z., 2019. Decomposition behaviour and mechanism of epoxy resin from waste integrated circuits under supercritical water condition. Journal Hazardous Materials 374, 356–364. https://doi.org/10.1016/j.jhazmat.2019.04.028

Acknowledgments

This work received financial support from the PT national funds (FCT/MECI, Fundação para a Ciência e Tecnologia and Ministério da Educação, Ciência e Inovação) through the project UID/50006/2025 DOI 10.54499/UID/50006/2025 - Laboratório Associado para a Química Verde - Tecnologias e Processos Limpos; FCT/MECI: LEPABE, UID/00511/2025 (https://doi.org/10.54499/UID/00511/2025), UID/PRR/00511/2025 (https://doi.org/10.54499/UID/PRR/00511/2025) LA/P/0045/2020 (https://doi.org/10.54499/LA/P/0045/2020).