Novel multi-stage aluminium production: part 1 – thermodynamic assessment of carbosulphidation of Al2O3/bauxite using H2S and sodiothermic reduction of Al2S3. Issue 2 (3rd April 2018)

• Record Type: Journal Article
• Authors: Rhamdhani, M. A.; Huda, N.; Khaliq, A.; Brooks, G. A.; Monaghan, B. J.; Sheppard, D. A.; Prentice, L.
• Is Part Of: Mineral processing and extractive metallurgy. Volume 127:Issue 2(2018)
• Page Start: 91
• Page End: 102
• Publication Date: 2018-04-03
• Subjects: carbosulphidation of alumina -- indirect carbothermal reduction -- thermodynamic modelling -- carbosulphidation of bauxite -- aluminium sulphide production -- Al2S3 -- sodiothermic reduction of Al2S3; Ore-dressing -- Periodicals; Metallurgy -- Periodicals; Metallurgy; Ore-dressing; Periodicals; 669
• DOI: 10.1080/03719553.2017.1293352
• Languages: English
• ISSNs: 2572-6641

Abstract

ABSTRACT: A novel multi-stage Al production through a carbosulphidation of Al2 O3, followed by a sodiothermic reduction of Al2 S3, was proposed. In Stage-1, alumina (or bauxite) is reduced to Al2 S3 in the presence of carbon and H2 S. In Stage-2, Al2 S3 is reduced to Al through reactions with Na or NaH. The thermodynamic analysis predicted Al2 S3 to be the main intermediate Al-compound when H2 S is reacted with Al2 S3 and C at 1000-2000°C at 1 atm. Al2 S3 formation was predicted to be low at 1100-1300°C at 1 atm (0.1 moles/mole Al2 O3 ) but increased with increasing temperature (0.96 moles/mole Al2 O3 at 1800°C). The thermodynamic analysis of sodiothermic reduction predicted that Al metal can be extracted from Al2 S3 below 800°C at 1 atm. The Na2 S produced can be hydrolysed to form H2 S and NaOH. H2 S can be re-used and the Na can be reproduced from NaOH and put back into the process.