Coordination Funds

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The Megatrends we are facing today can be summarized under the question: “How can we as part of the society become more efficient to achieve a sustainable use of all the natural resources?” This question comprises the CO2/energy as well as the raw materials/recycling (waste) challenge. Nowadays, recycling technology is at the crossroads. In developed countries, recycling technologies have evolved to recover those elements and materials, which represent the main mass of waste, but we are lacking technologies to address the essential and often rare elements of a modern society, which become dissipated in the waste streams. Such rare elements provide typically a special functionality to a product, they are contained in batteries, capacitors, magnets, electronic circuits, sensors and functional composite structures in general. One significant sink for a large number of these elements are pyrometallurgical processes, recovering metals, since these processes aim traditionally at the quality, yield and economic importance of the main metal phase. All non-functional elements and those which effect the material quality are forced to migrate to the second liquid phase, the slag phase. The latter consists of oxides, phosphates, carbonates and sulfides of metals and metalloids. Thus, the slag becomes the carrier of a broad number of valuable elements. The concentration of these elements is low and therefore they are dissipated and integrated into the inorganic matrix after solidification. A common application of a slag, which contributes formally to a recycling rate, is as a filler, binder or geopolymer in construction, removing the contained critical elements entirely from any material cycle. The PP 2315 EnAM addresses the slag phase as an important source for critical technology elements. When the slag solidifies it either can form a homogeneous amorphous structure or it can generate crystals. These crystals can be seen as artificial minerals, ores respectively. Thus, a specific crystallization of defined minerals is potentially able to concentrate diluted elements by orders of magnitude. To generate these crystals, it can be required to add further species, for that defined minerals formation. The formation itself depends on the thermodynamics of the complex multi-component slag system. The identification of an EnAM-crystal is only the first step in the processing route. It has to be crystallized to a sufficient size (e.g. < 10 µm) and stability, liberated from the remaining sometimes partially amorphous solid matrix. Finally, the mechanical separation of the EnAM-particles leads to a new artificial ore concentrate. Since slag processing until now is waste processing, we are lacking strategies and process laws, e.g. breakage laws or flotation strategies for the quantitative description and modeling. In summary, the PP 2315 works on holistic separation and concentration concepts, which wil allow to keep more elements in the material circle in the future.