From the Art of Blowpipe Analysis to Battery Recycling

Von der Lötrohrprobierkunst zum Batterierecycling
Von der Lötrohrprobierkunst zum Batterierecycling

The Institute of Metallurgical Process Engineering and Metal Recycling at RWTH was founded 125 years ago. The story begins with Wilhelm Borchers.

The Institute and Chair of Metallurgical Process Engineering and Metal Recycling (IME) at RWTH Aachen University aims to enable the sustainable management of metallic waste and residual materials and thus strengthen the supply of raw materials in the European economic area. The institute is one of the leading research centers in the field of metallurgical process technology and it demonstrated early on that metallic waste can be successfully recycled. The IME succeeded in protecting the "Green Metallurgy" trademark throughout Europe back in 2017. Metallurgical concepts and processes that are based on the idea of environmentally friendly, sustainable, zero-waste, and low-emission metallurgy are labeled with this name or logo.

There are many such success stories throughout the history of the IME. The story of the institute began exactly 125 years ago, an event that is now being celebrated together with the director’s 25th anniversary of service. Professor Bernd Friedrich has headed the chair since 1999, continuing a unique tradition. This tradition consists of former doctoral students of the chair holders taking over the holders’ positions. Friedrich succeeded Professor Joachim Krüger (1977 to 1999), who succeeded Professor Helmut Winterhager (1952 to 1977), who in turn succeeded Professor Paul Röntgen (1925 to 1952), while Röntgen succeeded the founding director Professor Wilhelm Borchers (1898 to 1925). "This consistency allows us to build close relationships with the graduates and to maintain a special alumni network in which we all know each other," says Friedrich.

We Have Gradually Expanded Upon our Expertise

The history of the IME begins with Borcher’s full professorship in "Metallurgy and Electrometallurgy" at the Rheinisch-Westfälische Polytechnische Schule. This was preceded by two offshoots from the "Chair of Mineralogy and Metallurgy", the "Chair of General and Special Metallurgy and Mineral Resource Estimation" and Borcher’s "Chair of Metallurgy and Blowpipe Analysis". The tasks included the processing of complex ores and alloy development. There was a large smelting laboratory, a testing laboratory, and an analytical laboratory for this purpose. Borchers established the new field of metallurgy - initially in the Main Building on Templergraben, then in the cellars of the Mining Building on Wüllnerstraße. His achievements are still visible everywhere. His successors gradually expanded upon his expertise in this field.

The topics became more complex: Metallurgy and recycling, materials science and metallurgy, electrometallurgy, even docimacy (determination of the content of gold and other precious metals) became part of teaching and research under Paul Röntgen, for example. Incidentally, he was also the first post-war rector of RWTH and he was significantly involved in the reconstruction and reopening of teaching. The reconstruction also included the company’s own institute rooms in the "Naumann Institutes for Metallurgy in its Entirety", which were opened in 1906 on what is now Intzestraße.

His successor Helmut Winterhager was also Rector of the University in the meantime (as was Borchers) and, during his time as chair, recorded a huge increase in diploma theses (from 92 to 227) and dissertations (from 54 to 70). His successor, Joachim Krüger, was then able to take on the challenge of restructuring the metallurgy and materials engineering degree courses and, in research, topics such as environmentally friendly resource recovery/environmental protection technology really came into focus for the very first time.

New Name for the Chair

The laboratories were now equipped with direct current arc furnaces, short rotary furnaces, electron beam furnaces, and much more. In order to meet today’s requirements, the equipment pool has been expanded upon considerably over time. This was also made visible under Bernd Friedrich by renaming the chair "Metallurgical Process Engineering and Metal Recycling". "The challenges have changed, and we have taken this into account with our new name," says Friedrich. "We have always been able to rely on a well-functioning team and this has contributed to the success of the IME over the years." Over 120 doctoral students have now been involved in research and almost 500 student theses have been supervised.

Research topics today include the recovery of valuable materials, in particular economically critical materials from batteries, electronic waste, and catalytic converters at the end of their useful life, wastewater treatment, remelting technology, and the transformation of mineral waste into products. These are just a few examples of the fields in which the metallurgists [?] work. The subject of battery recycling is particularly prominent, and it has been a focus of Accurec GmbH’s work since 1999. Using its experimental platform, the IME generates considerable research funding up to pilot scale and it exceeded the five million euro mark in third-party funding during 2019.

At the same time, research is the foundation for spin-offs such as the young companies cylib and tozero. In addition to third-party funding, the number of students and publications is increasing and, last but not least, the IME boasts a good amount of active international collaborations - such as a partnership with the University of Cape Town, the University of Belgrade, the Norwegian University of Science and Technology NTNU, and many others. Furthermore, senior engineer Dr. Alexander Birich was awarded RWTH’s Intspire Prize for his contribution to internationalization this year.

During the Faculty’s 2018 strategy process, the topic "Advanced Circular Economy" was discussed at the IME’s request. The result is highly visible today: The end result was the founding of the interdisciplinary Center for Circular Economy; Friedrich is the spokesperson for the Center. "All faculties can relate to this topic; the center truly lives the interdisciplinary nature of the University, and it embodies its Sustainability Strategy. We have also been able to establish a close relationship with the City of Aachen," explains Friedrich. "It’s all very ambitious."