Novel industrial applications for the separation and recovery of metals through the use of aqueous biphasic systems

The thesis project is developed within the framework of metal recycling. The company Aperam, world leader in the production of stainless steel, decided to launch a new line of investigation to clean up the pickling baths used during the steel processing. New recycling processes based on the use of aqueous biphasic systems have been developed for this purpose. In particular, two pickling baths were investigated during the PhD. The UGCO bath, characterized by a high amount of iron in a hydrochloric medium, was treated with different agents, called biphasic inducers, in order to clean it of most of the metals not essential for the pickling process. The proposed systems did not immediately meet the company's requirements, but on the other hand, thanks to this line of research, new systems called AcABS (acid-based ABS) have been developed which may be useful on an industrial level. The second bath analyzed was the sulphate bath, rich in Cr(VI). A patent was obtained for this second bath, in which the recovery of the metal was achieved through the use of a specific family of polymers.

Direction/co-encadrement : Dr Isabelle Billard (Directrice de thèse), Dr. Ismaël Guillotte (Société Aperam), Dr. Lenka Svecova

Composition du jury :
Pr. Joao Coutinho, Université d'Aveiro, Portugal
Dr. Natalia Plechkova, School of Chemistry and Chemical Enginerring, Belfast, Royaume-Uni, rapporteure
Pr. Laurent Dupont, Université de Reims, rapporteur
Pr. Marian Chatenet, UGA