| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Bauxite Residue Valorization and Best Practices
|
| Presentation Title |
Assessing the Carbonation Potential of De-alkalized Bauxite Residue Using Different Carbonation Methods |
| Author(s) |
Fabio Oliveira, Tobias Hertel, Yiannis Pontikes |
| On-Site Speaker (Planned) |
Fabio Oliveira |
| Abstract Scope |
This study investigates the carbonation potential of de-alkalized bauxite residue (DABR) under various methods. DABR was carbonated in slurry, dry powder, and wet powder states using three techniques: exposure to air; exposure to CO2 in a chamber at 50 °C; and exposure to CO2 pressure in an autoclave at 50 and 100 °C. After carbonation, CO2 uptake was measured via thermogravimetric analysis (TGA), mineral composition was determined by x-ray diffraction (XRD), and reactivity was assessed using the rapid, relevant, and reliable (R3) test. The results indicated that hydrogarnet is the only phase in DABR susceptible to carbonation, forming CaCO3 and an amorphous phase. Nearly all carbonation in the CO2 chamber occurred within one day, achieving a CO2 uptake of about 9%, which significantly offsets CO2 emissions attributed to the lime added during the de-alkalization process. The R3 tests showed low cumulative heat, indicating low reactivity of the carbonated DABR. |
| Proceedings Inclusion? |
Planned: TMS Journal: Journal of Sustainable Metallurgy |
| Keywords |
Process Technology, Recycling and Secondary Recovery, Sustainability |