Critical raw materials (CRMs) are crucial for the transformation towards low carbon mobility. However, their production is often highly concentrated in a few countries, which leads to supply risks. Exemplified by the case of rare earth elements (REEs) and based on in-depth interviews with corporate executives from companies along the automotive supply chain, this contribution provides insights into the strategies of the European automotive industry to cope with these supply risks. Results show a lack of awareness of REE criticality studies and their outcomes in the past, the decisive role of price competitiveness when pursuing mitigation strategies and a lack of willingness or ability to engage in rare earth (RE) projects to get access to production output and secure supply. Overall, affected companies struggle to pursue long-term oriented strategies to secure their need for REEs. These findings are discussed with regard to the new demand for CRMs due to the shift to electric mobility and the specific challenges that the automotive industry faces.

Eudialyte-group minerals (EGM) attract global interest as potential resources for high-field-strength elements (e.g. Zr, Nb, Ta, and rare-earth elements), i.e. critical materials for modern technologies. They are particularly valued for their relative enrichment in the most critical lanthanides, i.e. Nd and heavy rare earth elements (Gd–Lu). However, rare earth element (REE) substitution mechanisms into the EGM structure are still poorly understood. Light and heavy REE may occupy different sites and there may be ordering and/or defect clustering in the structure. This study uses X-ray absorption spectroscopy to determine the structural state of REE in EGM from prospective eudialyte-bearing complexes. Yttrium K-edge and Nd L3-edge spectra were collected as proxies for heavy and light REE, respectively, and compared to natural and synthetic REE-bearing standards. Extended X-ray absorption fine structure data yield best fits for Y in six-fold coordination with Y–O distances of 2.24–2.32 Å, and a second coordination sphere comprising Fe, Na, Ca, Si and O at radial distances of 3.6–3.8 Å. These findings are consistent with dominant Y3+ substitution for Ca2+ on the octahedral M1 site in all the samples studied, and exclude preferential substitution of Y3+ onto the smaller octahedral Z site or the large low-symmetry N4 site.

Using lattice strain theory, we constructed relative partitioning models to predict site preferences of lanthanides we have not measured directly. The models predict that all REE are favoured on the Ca-dominant M1 site and that preferential partitioning of heavy over light REE increases in EGM containing significant Mn in the M1-octahedral rings (oneillite subgroup). Thus, the flat REE profiles that make EGM such attractive exploration targets are not due to preferential partitioning of light and heavy REE onto different sites. Instead, local ordering of Mn- and Ca-occupied M1 sites may influence the capacity of EGM to accommodate heavy REE.

As the global economy grows and evolves in the 21st century emerging technologies will require mineral commodities on a greater scale and in a larger number of applications than ever before. The explosive growth in the economies of other nations and the concomitant and explosive increase in demand for raw materials are the reasons for potential supply restrictions. The portfolio of minerals and metals needed for manufacturing is dynamic. If the supply of any of the raw materials used in everyday products and in new emerging technologies was curtailed, many high-tech sectors of the European industries could be significantly affected. For example, the so called “tuning metals” or “spice metals”, although used only in small and essentially as “functional alloyings” in conventional metals are indispensable as “power amplifier” of modern materials used in vehicle construction. These materials are in principle recyclable. However, in most cases it is impossible to recycle them because of the minor concentration in application, thus they are being “consumed”. The Faculty of Georesources and Materials Engineering of RWTH Aachen University is initiating thereupon an integrated interdisciplinary research. The three divisions of the faculty, i.e. Raw Materials and Waste Disposal Technology, Metallurgy and Materials Technology as well as Geosciences and Geography, collaborate on the issue of sustaining critical raw materials availability so that the supply of materials needed for futures industries can be guaranteed. Objective of this research cooperation is to develop life-cycle strategies for critical raw materials which are fundamental for emerging technologies. Securing the availability of raw materials may be accomplished by improving the efficiency of the raw materials chain and by enhancing the raw materials base. Increasing also the knowledge base in this field will enable the European society to transfer more resources into economically efficient and technically manageable as well as politically and socially acceptable mineral and metal reserves. Assuring a sustainable availability of critical metals will be of paramount importance for technical innovations. Researchers and scientists from the Faculty of Humanities at RWTH Aachen University are also involved to study the relation between raw materials supply and economic as well as social matters. Mapping out sustainable strategies for securing the supply of raw materials in the long run requires the competence and input of scientists in fields of natural, engineering, political, economical, and social sciences. Demand and supply of raw materials are affected by the economy, whereas global political and social issues have impact on the same economy.