| About this Abstract |
| Meeting |
2021 TMS Annual Meeting & Exhibition
|
| Symposium
|
Alumina and Bauxite
|
| Presentation Title |
Bauxite Residue Neutralization Potential Using Biogenic Sulfuric and Citric Acids |
| Author(s) |
Patricia Magalhães Pereira Silva, Roseanne Barata Holanda, Andre Luiz Vilaça do Carmo, Fernando Gama Gomes, Raphael Vieira da Costa, Caio César Amorim de Melo, Adriano Reis Lucheta, Marcelo Montini |
| On-Site Speaker (Planned) |
Adriano Reis Lucheta |
| Abstract Scope |
Attenuation of high alkalinity and sodicity in bauxite residue (BR) is a fundamental requirement for its use in alternative large-scale applications, such as agriculture and building materials. The high chemical neutralization cost is one of the main limitations for broad BR use. This study applied a biotechnological approach to ameliorate BR characteristics by using ex-situ biogenic sulfuric (H2SO4) and citric (C6H8O7) acids produced by Acidithiobacillus thiooxidans and Aspergillus niger, respectively, in comparison with their analytical ACS grade equivalents. Batch tests containing BR (20% w / v) mixed with acidic solutions were conducted followed by solid (XRD, XRF, SEM) and liquid (pH, EC, ICP-OES) phases evaluation. Results showed that the biogenic H2SO4 was more effective for the BR partial pH neutralization (final pH ~8) and sodicity decreasing (35% reduction) when compared with biogenic C6H8O7 and H2SO4 ACS grade, indicating the potential of this biotechnological route for the BR amelioration prior use. |
| Proceedings Inclusion? |
Planned: Light Metals |