RAMR2D network scholarship holders
Affiliated project: IRD
CEA affiliates: Institut Supérieur des Mines et Géologie de Boké CEMS, Institut National Polytechnique Houphouët Boignet CEA- MEM
Thesis supervisor: Alphonse Yao Kouakou Institut National Houphouet Boigny
alphonse.yao@inphb.ci
Thesis co-supervision: Clément Levard CEREGE
levard@cerege.fr
Other contributors to thesis supervision: Sekou Traoré Institut Supérieur des Mines et Géologie de Boké
sktraore@gmail.com
OULARE Pierre Tamba
Affiliated project: IRD
CEA affiliates: Institut Supérieur des Mines et Géologie de Boké CEMS, Institut National Polytechnique Houphouët Boignet CEA- MEM
Thesis supervisor: Alphonse Yao Kouakou Institut National Houphouet Boigny
alphonse.yao@inphb.ci
Thesis co-supervision: Clément Levard CEREGE
levard@cerege.fr
Other contributors to thesis supervision: Sekou Traoré Institut Supérieur des Mines et Géologie de Boké
sktraore@gmail.com
Title: Evaluation of the potential of alumina production residues from the Rusal Friguia plant in the Republic of Guinea for the extraction of rare earths.
Summary of scientific project:
The production of critical metals from secondary resources is essential to support the development of the technologies that depend on them, particularly those linked to the energy transition.
In the context of the circular economy, mining and industrial waste represent largely under-exploited secondary rare earth resources.
Large quantities of red mud have been generated since 1960 at the Rusal friguia plant in the Republic of Guinea, without any significant recovery.
These sludges are stored and present a significant environmental risk due to their alkalinity (pH˃12) and the presence of heavy metals.
Summary of results obtained :
In order to increase the visibility of this work, we have extended the initial study to karst sludges produced in the Marseille region over the last century.
With the aim of valorizing these residues, characterization and selective dissolution studies of rare earths under mild pH conditions have been carried out.
Differences in the speciation of heavy rare earths have been observed depending on the geological origin of the sludges. Leaching and optimization experiments were carried out according to a Box-Behnken design. We have shown that the origin of the bauxite influences the speciation and dissolution of rare earths in the bauxite residue.
Prospects for the end of the thesis:
By the end of the thesis, I wish to strengthen my capabilities in the field of geosciences and subsequently further investigate the potential of tailings for critical metals other than rare earths in order to consider future research prospects.
Publish more of my research results.
Prospects after completion of the thesis:
After completion of the thesis, I intend to popularize the results of my research through international communications. I will also explore ways of making these results viable.
Scientific publications :
https://www.sciencedirect.com/science/article/abs/pii/S0304389423022252?via%3Dihub
Contribution / added value to the affiliated project :
This thesis project is of the utmost importance for its impact on the local, regional and international scientific community in terms of improving learners' skills in the various mineralurgical and metallurgical processes employed. In this sense, it could promote the complementarity of skills between the doctoral student and the centers involved. On a local level, this thesis project would create an ideal living environment for Rusal Friguia's workers and, above all, for the community living near these storage sites.