Hydrogen in Treatment of Bauxite Residues

Authors

  • Srećko Stopić IME Process Metallurgy and Metal Recycling, RWTH Aachen University, Germany
  • Duško Kostić IME Process Metallurgy and Metal Recycling, RWTH Aachen University
  • Vladimir Damjanović Alumina Ltd. Zvornik, 3Institute for Multidisciplinary Research
  • Radislav Filipovic Alumina Ltd. Zvornik, 3Institute for Multidisciplinary Research
  • Nenad Nikolić Institute for Multidisciplinary Research
  • Mitar Perušić Faculty of Technology Zvornik, University of East Sarajevo

Abstract

This study explores pyrometallurgical and hydrometallurgical methods for decarbonizing and recovering valuable metals from bauxite residue, with direct hydrogen reduction in a rotary kiln without smelting and dissolution of solid residues under high pressure in an autoclave. The goal is to offer decarbonizing techniques for the removal of iron from bauxite residue, a by-product of the Bayer process, which cannot be disposed of in an environmentally sustainable manner. In contrast to traditional carbon-based reductive melting, which generated significant CO₂ emissions, hydrogen is now being investigated as a cleaner alternative. Through hydrogen reduction in rotary kiln, approximately 99.9% of iron is recovered as iron, which can be separated using magnetic separation from the solid residue containing other valuable metals. We concluded that hydrogen can reduce iron oxide from bauxite residues to metallic iron in contrast to very stable oxides such as titanium oxide, silica and aluminum oxide. Leaching of titanium, iron and aluminum with sulfuric acid has high efficiency under high pressure in an autoclave.

Keywords:

reduction, hydrogen, bauxite residue, decarbonizing

References

Damjanović, Vladimir, Radislav Filipović, Zoran Obrenović, Mitar Perušić, Duško Kostić, Slavko Smiljanić, and Srećko Stopić. “Influence of process parameters in three-stage purification of aluminate solution and aluminum hydroxide.” Metals 13 (2023): 1816.

https://doi.org/10.3390/met13111816

Jovičević-Klug, Matic, R. Isnaldi Souza Filho, Hauke Springer, Christian Adam, and Dierk Raabe. “Green steel from red mud through climate-neutral hydrogen plasma reduction.” Nature 625 (2024): 704–717.

https://doi.org/10.1038/s41586-023-06901-z

Stopić, Srećko, Duško Kostić, Richard Schneider, Magnus Sievers, Florian Wegmann, Elif Emil Kaya, Mitar Perušić, and Bernd Friedrich. “Recovery of titanium from red mud using carbothermic reduction and high pressure leaching of the slag in an autoclave.” Minerals 14 (2024): 1151.

https://doi.org/10.3390/min14111151

Stopić, Srećko, Nenad Nikolić, Dragana Životić, Jugoslav Krstić, Milena Rosić, Vladimir Damjanović, and Bernd Friedrich. “Hydrogen metallurgy for a treatment of bauxite residues – First results on the EURO-TITAN Project.” In Proceedings of the XXV YUCORR Conference, Divčibare (2024): Plenary Lecture, 1–11.

Stopić, Srećko, and Bernd Friedrich. “Formation and application of hydrogen in non-ferrous metallurgy.” Military Technical Courier (2023): 783–796.

Published

31-03-2025

Issue

Section

Sustainable Industrial Waste Processing