Catalysis with recycled metals: from waste to wealth – CAREME

Electronic waste appears to be an attractive alternative to natural minerals for the supply of precious metals to western economies. However, its exploitation remains limited, mainly for reasons of scale, due to the high variability of the collected materials. At the same time, the demand for precious metals for chemical applications is increasing, due to their performance in homogeneous and heterogeneous catalysis. In this project, we propose to study efficient catalyst production cycles, directly from electronic waste, without going through the refining phase of precious metals. Such a development requires the control of the other elements contained in the waste (metals, organic, etc.), which can have a negative (or positive!) impact on the properties of use of the prepared catalysts. We propose to investigate the technical challenges associated with the approach in the field of platform and fine chemicals synthesis, through detailed investigations on selected applications in homogeneous and heterogeneous catalysis, with a focus on palladium, one of the most valuable metals neglected during e-waste reprocessing.
The scientific purpose of the project is to study the impact of impurities (organic and inorganic) originating in the processing of e-waste on the activity of catalysts. Our goal is not to develop new catalysts, but to prepare and fully characterize precious metals based catalysts directly from e-waste, without isolation of the metals, with careful analysis of each step of the catalysts life. The project will bring useful knowledge on the possible synergies and antagonisms between targeted metal and impurities. The answer to this original scientific question is the key for the successful management of impurities profile during the entire e waste processing scheme, and the determination of the acceptable levels of these impurities according to the targeted applications. Building on these results, the project will include as a technological objective the large-scale preparation of a batch of catalyst, in order to achieve a validation in relevant environment (TRL 5), sufficiently detailed to enable a technical and economical evaluation of the proposed approach.
If a suitable treatment process can lead to a stream of metals of controlled composition, which in turn allows the manufacture of an efficient catalyst, the e-waste will be validated as an alternative source of precious metals. If this catalyst can then be integrated into existing industrial processes, including regeneration and recycling processes, then the demonstration that short economic circuits can be set up in our society will be made. This approach will lower our dependence on certain countries for these critical raw materials.