The Technologies for Sustainable Metallurgy (Tesmet) group is part of the Laboratory of Metallurgy at the National Technical University of Athens (NTUA), led by Professor Dimitrios Panias. With over thirty years of experience in metallurgical and materials engineering, Tesmet delivers fundamental, applied, and integrated research with an outlook on process innovation and sustainability. The group combines high-level infrastructure, a team of experienced professionals and strong bonds to the European raw materials ecosystem.

The group’s expertise covers pyrometallurgical, hydrometallurgical, and electrometallurgical processes, complemented by process modelling and analytical services. Its work extends from primary and secondary metal production— recovering resources from industrial by-products and end-of-life products— to the valorisation of industrial waste and the development of added-value products for the circular economy.

Within the HAlMan project, Tesmet plays a pivotal role in transforming by-products into valuable resources and developing sustainable material cycles. Their key responsibilities include:

• Production of alumina from secondary sources through hydrometallurgical processing.
• Recovery of critical raw materials (CRMs), such as strontium, and calcium from “grey mud” residues resulting from alumina production.
• Advanced modelling of leaching and precipitation processes using thermodynamics, CFD, and AI-ML predictive tools.
• Production of commercial aluminium-manganese alloys from ferromanganese alloys generated in HAlMan.
• Physicochemical analysis of primary and secondary raw materials, as well as materials from optimisation and pilot-scale campaigns.

Their process begins with the treatment of calcium aluminate slag, mixing it with sodium carbonate to form a sodium aluminate solution and a solid “grey mud” residue. Alumina hydrate phases are precipitated from the solution using CO₂ gas, while the residue undergoes selective recovery of strontium over calcium.

Tesmet’s innovation extends beyond processing to real-time process intelligence. Sensors monitor key properties of the precipitation solutions, feeding data into AI and machine learning models that predict composition on the fly, improving process control and efficiency.

By combining advanced process development, resource recovery, and data-driven modelling, NTUA’s Tesmet group is helping HAlMan deliver on its promise: demonstrating sustainable, low-carbon metallurgy while extracting maximum value from every stage of production.