Research » Technology Metals (Extraction and Recycling)
Critical metals are, by definition, metals that are of high economic importance and at the same time exhibit significant supply risks. Elements that are ascribed as especially critical are, for example, rare earth elements, platinum group metals, but also antimony and niobium.
At IME, pyrometallurgical as well as hydrometallurgical processes for economic, efficient and environmentally friendly treatment and extraction of critical metals are investigated. The following list abstracts some of our current research topics in this field:
– alternative Bismuth extraction route from lead industry residues
– extraction of rare earth elements from eudialyte ore via cascade leaching
– precious metal recycling by application of suitable slag systems
– extraction of antimony trioxide from lead industry residues
– metallothermic reduction of scandium compounds
Alumni:
- Dr.-Ing. Yiqian Ma
- M.Sc. Dominic Feldhaus
- M.Sc. Frederic Brinkmann
- M.Sc. Alexandra Daldrup
- M.Sc. Jürgen Maier
- M.Sc. Jil Schosseler
- Dr.-Ing. Diana Vieten, geb. Michaelis
- Dr.-Ing. Stephanie Kruse
- Dr.-Ing. Ann-Kathrin Maurell-Lopez geb. Pophanken
- Dipl.-Ing. Charlotte Merkel
- Dr.-Ing. Florian Ruschmann
- Dr.-Ing. David Friedmann
- Dr.-Ing. Marek Bartosinski
- Dr.-Ing. Milena Stopic
- Dr.-Ing. Hanno Vogel
- Dr.-Ing. Daniel Voßenkaul
- Dr.-Ing. Guizhi Zeng

Project List
Title
International Masters Programme in Energies & Green Hydrogen(IMP-EGH)
Type
Grundlagenforschung
Sponsorship
BMBF
Duration
15.02.2023 – 31.12.2025
Partner
Forschungszentrum Jülich – Deutschland; Institut für Eisenhütenkunde, RWTH Aachen – Deutschland; Felix Boigny Universität – Elfenbeinküste;
Description
The International Master Programme in Energy and Green Hydrogen (IMP-EGH) is innovative for the West African region, and it is designed to prepare the next generation to address the energy challenges of adaptation and resilience to Climate Change in West Africa. The programme’s interdisciplinary approach will allow for a better understanding of present-day energy infrastructures in West Africa, their strengths and weaknesses, energy policies, practices in a changing climate context and the search for sustainable solutions.
Title
SeRoBatt – Secondary sources of critical raw materials for battery cell production – potentials, recovery, resynthesis
Type
Verbundforschung
Sponsorship
EFRE/JTF-Programm NRW, mit Mitteln aus der EU
Duration
01.04.2024 – 31.03.2027
Partner
Fraunhofer FFB; Fraunhofer IWKS; FH Münster, IWARU; WWU Münster, MEET; elorec GmbH
Description
The EFRE-funded and thus EU co-financed project SeRoBat, which runs from 01.04.2024-31.03.2027, is researching the identification and development of secondary raw material sources from non-battery EoL products as well as reintegration into LIB test cells with final performance evaluation and limit value testing. Therefore, a material and material flow analysis will be carried out to identify relevant LiNMC-containing EoL products, as well as their useful life and disposal routes. This is to ensure that products are identified that are not derived from a functioning closed-loop system. As glass ceramics have already emerged as interesting EoL products, the focus will be on lithium recovery from glass ceramics. In addition, a material flow will be identified for each of the metals nickel, manganese and cobalt. The identified wastes will be procured, dismantled, pre-treated and the elements they contain recovered using hydro- and pyrometallurgical processes.
The project will be completed with a life cycle assessment and economic feasibility study to evaluate the economic viability of the procurement, dismantling, pre-treatment and recycling of EoL products for battery cell production.
IME project management: Jan Ole Krüger
Title
H2Giga Cluster (ReNaRe, Peuker)
Type
Verbundforschung
Sponsorship
BMBF
Duration
01.04.21 – 31.03.2025
Partner
TU Bergakademie Freiberg, Institut für Mechanische Verfahrenstechnik und Aufbereitungstechnik (TU BAF-MVTAT), Karlsruher Institut für Technologie, wbk Institut für Produktionstechnik (KIT-wbk), Fraunhofer-Institut für Produktionstechnik und Automatisierung (FhG-IPA), Helmholtz-Institut Freiberg für Ressourcentechnologie (HZDR-HIF), RWTH Aachen, Institut Metallurgische Prozesstechnik und Metallrecycling (RWTH-IME), TU Bergakademie Freiberg, Institut für Keramik, Feuerfest und Verbundwerkstoffe (TU BAF-IKFVW), Nickelhütte Aue GmbH (NHA), 8. Heraeus Deutschland GmbH & Co. KG (HDE), Öko-Institut e.V. (OEKO), DECHEMA Gesellschaft für Chemische Technik und Biotechnologie e.V. (DEC), Forschungszentrum Jülich GmbH (FZJ), Hexis GmbH, TU München, Professur für Circular Economy (TUM-CE)
Description
In this subproject of the ReNaRe network (technology platform H2Giga), the recycling of H2-electrolizer stacks is investigated. For this purpose, existing processes from FC recycling are to be validated and optimized, and innovative processes for electrolyser recycling are to be developed (focus on PGM, SEE, Ir, Ru, Ni, Co, Cr, Ti).
Title
ScaVanger. Sustainable supply of Nb, Sc and V from liquid waste from TiO2 plants
Type
Verbundforschung
Sponsorship
EIT Raw Materials
Duration
01.01.2021 – 31.03.2024
Partner
Orano Mining – France, Catura Geoprojects – France, ENALOS Research and Development – Greece, MEAB Chemie Technik GmbH – Germany, National Technical University of Athens (NTUA) – Greece
Description
In the Kic-project ScaVanger, scandium and other products are generated from residual materials from TiO2 pigment-production. In this way, the EU’s dependence on third countries for the import of critical metals and their compounds is decimated. For this purpose, the technology developed in the project is integrated into the TiO2 production facility. Hydrometallurgical processes are used to separate and purify the various metal compounds, and pyrometallurgical methods will be used to verify the metal production of Scandium and Niobium alloys.

Title
Development of an innovative process for the recovery of CoCr from dental residues
Type
Verbundforschung
Sponsorship
BMWi
Duration
01.06.2019 – 30.11.2021
Partner
EMH Service GmbH – Deutschland, RWTH-Aachen
Description
Within the framework of this project, an innovative and robust wet-chemical process for recycling the critical raw material cobalt and other metals from dental residues containing precious metals is to be developed. At the same time, precious metals are to be enriched in the leaching residue. As part of the implementation of the process in the plant, a leaching reactor is to be developed and included in EMH\’s product portfolio for sale in Europe.According to the state of the art, dental residues are treated only with the aim of recovering the precious metals, whereby the CoCr alloys can lead to process technical difficulties. For this reason, expensive recycling only pays off at higher precious metal concentrations of a few percent by weight. Large parts of today\’s dental residues cannot be treated economically and have to be disposed of.Translated with www.DeepL.com/Translator
Title
REGINA – Rare Earth Global Industry and New Applications
Type
Verbundforschung
Sponsorship
BMBF – Bundesministeriums für Bildung und Forschung
Duration
01.08.2017 – 31.07.2020
Partner
Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.; Fraunhofer-Projektgruppe IWKS (IWKS) Helmholtz-Zentrum Dresden-Rossendorf e.V. (HZDR), Helmholtz-Institut für Ressourcen-technologie (HIF) Technische Universität Clausthal (TUC) KME Germany GmbH & Co. KG (KME) Technische Universität Darmstadt (TUD) GMB Deutsche Magnetwerke GmbH (GMB) DMT-Gesellschaft für Lehre und Bildung mbH; Technische Hochschule Georg Agricola (THGA) Brasilien: Universidade Federal de Santa Catarina (UFSC) Fundação Centros de Referência em Tecnologias Inovadoras (CERTI) Universidade de São Paulo (USP) Instituto de Pesquisas Tecnológicas (IPT) Centro de Tecnologia Mineral (CETEM) Companhia Brasileira de Metalurgia e Mineração (CBMM) Agência Brasileira de Desenvolvimento Industrial (ABDI) Companhia de Desenvolvimento Econômico de Minas Gerais (CODEMIG) WEG S.A. (WEG)
Description
On August 1st, the BMBF-promoted project “REGINA” (Rare Earth Global Industry and New Application) started. The project will focus on the extraction of rare earths from Brazilian raw materials and the corresponding processing into magnets.
The main topic of the project will be the development of environmentally and socially compatible production and the development of a sustainable business model for a competitive marketing of the magnets. “Regina” is thus the partial continuation of the Siemens research field “Green Mining and Separation“ (ended 2015) and of the EURARE project „Development of a Sustainable Exploitation Scheme for Europe’s Rare Earth Deposits“ (ended 2017).
The IME’s task in this project is the production of Didym (NdPr) via molten salt electrolysis, the following refining and defined alloying in the vacuum induction furnace.
Title
Production of Scandium compounds and Scandium Aluminum alloys from European metallurgical by-products
Type
No information
Sponsorship
EU
Duration
01.12.2016 – 30.11.2020
Partner
Description
Scandium (Sc) is one of the highest valued elements in the periodic table and an element which is usually grouped in REEs as it shares many characteristics with Yttrium. Scandium technological applications are unique, as it is a key component in producing Solid Oxide Fuel Cells (Scandia-Stabilized-Zirconia solid electrolyte layer) or high strength Aluminum alloys used in aerospace and 3D printing applications (SCALMALLOY®). Yet Scandium supply is limited due to its scarcity and the high cost of its production, which currently takes place in Asia and Russia.
Europe has no production of Scandium, but is home to many Sc industrial end-users (Airbus, II-VI, KBM Affilips and others). In fact end-users like Airbus, are not deploying their Sc applications due to the lack of a secure Sc supply. The SCALE project sets about to develop and secure a European Sc supply chain through the development of technological innovations which will allow the extraction of Sc from European industrial residues.
Bauxite Residues from alumina production (5 Million tons on dry basis per year in Europe) and acid wastes from TiO2 pigment production (1.4 Million tons on dry basis per year in Europe) have Sc concentrations which are considered exploitable, given a viable extraction technology. SCALE develops and demonstrates the value chain starting from residue
and finishing to high tech end-product. In more detail:
• SCALE develops innovative technologies that can extract economically and sustainably Sc from dilute mediums (<100 mg/
L) and upgrade them to pure oxides, metals and alloys at lower energy or material cost.
• SCALE extracts along with Sc all other REEs found in the by-products (AoG’s BR on an annual base contain 10% of the
European REE raw material imports)
The industrially driven SCALE consortium covers the entire Sc value chain with 7 major European industries and further features 8 academic and research institutes and 4 engineering companies with track records in RTD.
Title
Integration of NRW recycling competencies into the European raw material community KIC EIT Raw Materials
Type
No information
Sponsorship
MIWF
Duration
01.07.2015 – 30.06.2018
Partner
Description
The aim of the project is to develop an efficient implementation strategy at regional level via the RWTH Core Partnership in the newly launched EU network project “EIT KIC Raw Materials” and to implement this strategy in NRW in the form of recycling-oriented EU projects funded by the EIT. In order to strengthen NRW as a recycling location, the RWTH Aachen University’s scientific competencies in the field of “secondary raw materials and recycling” are to be developed on an interdisciplinary basis and with industrial involvement.
– expanded and validated (technology area),
– communicated and taught (areas of education/technology) as well as
– technologically exploited close to the location (areas of entrepreneurship/technology)
IME project management: Elinor Rombach
Title
Transformative technologies for enhancing hydrometallurgical recovery rates of Li, Co and Ag
Type
No information
Sponsorship
BMBF
Duration
01.04.2016 – 31.03.2019
Partner
MEAB – Chemie Technik GmbH, MIMITech GmbH, University of Toronto, University of British Columbia, McGill university Montréal, UC Yukon Refinery AG, Barrick Gold Corporation
Description
Hydrometallurgical decomposition for the selective extraction of metals from various feedstocks plays an important role in metallurgy and is used extensively worldwide. The feedstocks can be primary raw materials such as ores or secondary raw materials such as residues from primary extraction or scrap. An important advantage of hydrometallurgy is the low energy requirement, as the processes take place at low temperatures. Another important advantage is the possibility to treat low concentrated resources because valuable metals can be extracted selectively.
Title
Development of a sustainable process route for the internal European processing of bismuth trees by combining innovative refining processes
Type
No information
Sponsorship
BMBF
Duration
01.09.2016 – 30.08.2019
Partner
BBH Stolberg, Aurubis AG, GTT Technologies-Deutschland
Description
As part of the BMBF call for proposals “Innovative Technologies for Resource Efficiency – Research for the Provision of Economic Strategic Raw Materials”, an innovative, economic and environmentally friendly project will be presented below. The aim of the “BiRec” project is to develop a metallurgical process with which it will be possible to further enrich the resulting bi-containing foams from the Kroll-Betterton process with bismuth and then refine them without using critical processes.
Title
German Resource Research Institute – GERRI
Type
No information
Sponsorship
BMBF
Duration
01.02.2015 – 31.01.2020
Partner
Helmholtz-Zentrum Dresden-Rossendorf, HIF/ HZDR, TU Bergakademie Freiberg, vertreten durch TUBAF, TU Clausthal, vertreten durch TUC, Fraunhofer-Institut
Description
The aim of the project is to establish a national nucleus or a virtual institute for coordinated joint research in the field of primary and secondary inorganic raw materials (mineral and metallic) along the entire supply chain with a special focus on the international environment.
The purpose of the project is to create transparency about the core competences and infrastructures of the partners along this chain in the field of economically strategic raw materials, in order on the one hand to better present and more effectively use existing complementarities and synergies and on the other hand to be able to coordinate the future orientation (e.g. research strategy, new acquisitions, etc.) in a target-oriented manner. The national network will establish or intensify cooperation with the state authorities of the partners to be networked.
IME project management: Elinor Rombach
Title
Recyclability of rare metals when dismantling nuclear facilities
Type
Grundlagenforschung
Sponsorship
BMBF
Duration
01.09.2014 – 29.02.2016
Partner
Institut für Nukleare Entsorgung und Techniktransfer (NET) RWTH Aachen-Deutschland
Description
The main objectives of the preliminary study are the estimation and classification of the quantities of non-radioactive valuable non-ferrous metal containing recycling raw materials and the evaluation of how these raw materials can be recovered from the components in a resource-efficient way after optimal processing and metallurgy.
IME project management: Elinor Rombach
Title
Core-Partner Beteiligung an Knowledge and Innovation Communities-Umsetzungsstrategie im KIC InnoLife und KIC Raw MatTERS
Type
Verbundforschung
Sponsorship
RWTH- Strategiefonds
Duration
01.01.2015 – 31.12.2017
Partner
RWTH-IMA (Lehrst. Informationsmanagement im Maschinenbau)-Deutschland, RWTH-WIN (Lehrst. Wirtschaftswissenschaften für Ingenieure u. Naturwissenschaftler)-Deutschland, RWTH-AMR (Aufbereitung mineralischer Rohstoffe)-Deutschland
Description
As part of the new KIC (Knowledge and Innovation Community) funding instrument, the EIT (European Institute of Innovation and Technology) regularly launches themed calls for long-term international network projects between partners from education, research and industry. The task of these KICs is innovation-oriented top-level research in areas of central economic/social interest and the dissemination/commercialisation of innovations, which should ultimately increase European competitiveness. In clear contrast to conventional EU funding, the aim is to make R&D projects marketable, promote entrepreneurship in Europe and establish new industry-orientated/interdisciplinary training concepts.
Through its participation in the EIT funding instrument KIC, RWTH Aachen University has made a fundamental commitment to actively utilising this resource to expand areas of expertise in research and teaching. The aim of this project is to develop an efficient implementation strategy for the KICs InnoLife and Raw MatTERS at a central and scientific level, through which KIC can be used as an innovative funding resource to increase professional expertise, international visibility and, possibly, the acquisition of third-party funding for RWTH Aachen University.
During the reporting period, the “RWTH Raw Materials Group” carried out numerous activities at various levels in order to increase the international visibility and expertise of RWTH Aachen University in the field of primary mineral/metalliferous raw materials. Here, synergy effects could be optimally utilised through joint work with RWTH specialists from the parallel MIWF-NRW support project, particularly in the areas of public relations and the integration of RWTH’s own network structures. In return, the “RWTH/NRW recycling group” benefited from input and regular dialogue, particularly with the non-specialist members of the RWTH administration team from the “RWTH Raw Materials Group”.
IME project management: Elinor Rombach
Title
KIC Raw Materials – Application by RWTH Aachen University
Type
No information
Sponsorship
MIWF
Duration
01.10.2013 – 15.12.2014
Partner
HIF Freiberg, TU Freiberg, TU Clausthal, CUTEC Clausthal, Fraunhofer ISC Würzburg bzw. IWKS Hanau/Alzenau, Fa. Recylex-Deutschland
Description
Participation in the preparation of the application by the European consortium KIC Raw MatTERS, participation in the working groups, preparation of a KIC industry network “Recycling”.
IME project management: Elinor Rombach
Title
EURARE: Development of a sustainable exploitation scheme for Europe\’s Rare Earth ore depoits
Type
No information
Sponsorship
EU
Duration
01.01.2013 – 31.12.2017
Partner
Technical University of Athens,Katholieke Universiteit,Sveriges Lantbruksuniversitet,Instituto Geologikon Kai Metalleytikon Ereynon,Sveriges Geologiska Undersokning,Geologian Tutkimuskeskus, Geologica
Description
Raw materials are essential for the functioning of the economy of industrialised regions like the EU. The global demand for non-energy raw materials has experienced an unprecedented growth in the 20th century, with the United States of America and Europe being the dominant users of raw materials. Industrial sectors such as automotive, aerospace, machinery, chemicals and construction are completely depended on access to certain raw materials. The notable increase in raw material consumption during the last years, mainly by the so called BRIC economies, with the acronym standing for Brazil, Russia, India, and China, the geographically uneven distribution of earth’s mineral resources, the intense exploitation of most of the sizeable and high grade deposits in Europe and the restrictions on foreign investments and exports recently posed by China, make the supply of raw materials at reasonable prices one of the greatest challenges for the EU in the 21st century.
Title
Direct low-process extraction of solar silicon from raw silicon while avoiding silane chemistry
Type
No information
Sponsorship
Deutsche Bundesstiftung Umwelt
Duration
01.10.2006 – 31.3.2008
Partner
ACCUREC GmbH Mülheim-DE
Description
The aim of the project is the development and testing of an innovative process for the production of high-purity silicon, which is required for the production of solar wafers. Today, this silicon, known as solar grade (SG), is obtained almost exclusively from so-called off-grade material, i.e. scrap material from the semiconductor industry, and is a by-product of a process that is far oversized in terms of purity for SG silicon. Thus the available quantity is limited and can no longer satisfy the demand of the accelerating photovoltaic market. In addition to the price-driving shortage of this input material, the technically complex and expensive production processes for ultrapure silicon prevent a necessary cost reduction so that solar energy can compete in the future without subsidies. Significant savings in the process chain of a solar wafer can only be achieved if an alternative process to today’s SG-Si extraction process can be found, the Siemens process which involves the chlorination, gasification, condensation and dechlorination of silicon.
Title
Preparation of a German contribution to the European revision of the „Reference document on Best Available Techniques in the Non Ferrous Metals Industries“ (briefly: NE-BREFs)
Type
Verbundforschung
Sponsorship
UBA
Duration
01.03.2006 – 31.08.2007
Partner
Description
The available UBA research project was given in order to the IME Process Metallurgy and Metal Recycling of the RWTH Aachen in spring 2006 for making a German con-tribution to the European revision of the reference document published in the year 2002: „Reference document on Best Available Techniques in the Non Ferrous Metals Industries“ (briefly: NE-BREFs). Within the framework of evaluating these European BAT-documents, the German production and processing technologies of the major commercial metals copper, aluminium, lead and zinc were reviewed in the sense of production-integrated environmental protection (generally up to first melt solidification stage).
Purpose was to close suitable data gaps of the present NE-BREFs as far as possible, to update the technological standard achieved in Germany as well as to describe relevant new developments. In addition it was tried to deepen the topic of the processing of aluminium salt slags, the dross recovery, the emissions for particulate matter, the capture of fugitive emissions, the post-combustion systems, the activated carbon technique and the costs specific for environment. This was done in close co-operation with the concerning non ferrous metal industry (8 reference plants + approx. 30 other Germans plant locations). In Germany stated shut-downs of processes were excluded from a further consideration. In analogy to the current NE-BREFs the subject areas alumina production respectively anode production (aluminium) as well as sulfuric acid production respectively oxide and pigment production (lead, copper, zinc) expressly were not or were regarded only on the edge.
In August 2007, the approx. 220 sides strong national report contribution to European information exchange has been finished. In this report current information relevant to environmental protection is given, analogous to the current reference document. Here, the major applied BAT-technologies and the related materials and energy flows oc-curring as well as cost data, where available, are stated. Beside those updates and additions made in English, the reference document is commented in German where necessary.
IME project management: Elinor Rombach