Department of Metallurgy and Recycling
Non-ferrous metals are indispensable for the economies of high-tech industrialized countries. They are employed in many ways, for example in electrical or mechanical engineering, vehicle manufacturing, and in the construction sector. Although there are already many recycling and extraction processes for some non-ferrous metals such as aluminum, lead or copper, there is a significant need for research on other non-ferrous metals such as rhenium, gallium, indium, germanium, and rare-earth metals. The elements are often found in very small concentrations in primary or secondary raw materials, which leads to a difficult extraction of these elements.
That is the reason why scientists in the Metallurgy and Recycling Department are primarily developing energy-efficient and cost-effective processes for recycling these and other valuable elements from electronic scrap, process wastewater, waste rock pile material and process dust. Furthermore, they investigate and optimize processes for sustainable metal extraction from primary raw materials. To do so, researchers study hydro- and pyro-metallurgic processing methods. They develop these innovative technologies in interdisciplinary cooperation with other Departements at the Helmholtz Institute Freiberg for Resource Technology.
The Department of Metallurgy and Recycling Conducts Research in the Follow Areas
- Solvent extraction (Liquid-liquid-extraction)
Ongoing Research Projects
By smart combinations of existing and new methods, CHROMIC partners develop new chemical and physical processes to recover chromium, vanadium, molybdenum and niobium industrial wastes. The new processes will be tested and validated to extract valuable and critical metals in the most sustainable way. The goal is to create a “circular economy” for these metals, one where all resources are kept at the highest possible level of functionality and value at all times.
Recycling Theisen Sludge from the Mansfelder Smelting Process
Theisen sludge, a by-product of the copper-slate (Kupferschiefer) smelting process formerly executed in the region of Mansfeld in Germany, contains zinc, lead, copper and tin, as well as economically valuable trace elements like germanium or rhenium. The r4 project which is funded by the German Federal Ministry of Education and Research (BMBF) aims at developing a ready-to-use process in order to recycle Theisen sludge efficiently.
Molecular Containers for Extracting Rare Earths (SE-FLECX)
Under the coordination of the Helmholtz Institute Freiberg for Resource Technology experts from research and industry are testing if so-called calixarenes could be used as an alternative extraction agent in the industrial separation of rare earths. The organic macro molecules are expected to simplify the enrichment of these metals and significantly decrease the use of process chemicals.
Germanium from Fiber Scraps
Fiber-optic cables are the backbone of modern telecommunications networks and they contain the rare metal germanium. The Division of Metallurgy and Recycling develops a pyro-metallurgic process to cost-efficiently and efficiently recycle the metal from fiber scraps resulting from the production of fiber-optic cables.
Recycling of Flue Dust Containing Zinc and Copper
So-called flue dust results from the pyro-metallurgic processing of ores in order to produce metals such as copper and zinc. These flue dusts also contain economically strategic metals like indium, gallium and tin, as well as other elements like lead that pose a challenge for waste disposal. The project InGa-SX aims to develop a ready-to-use process to recycle these dusts (and metals they contain), which have already been partially deposited.