Influence of Grain-Size Composition of Bauxite on Its Recovery at Fria Aluminum Plant in Guinea

Béavogui, Marie Constance; Balmaev, B. G.

doi:10.25018/0236-1493-2017-9-0-131-138

Cited by 2 publications

(2 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The extraction of these elements from BR, together with a reduction in its toxicity, can be economically and ecologically beneficial. For example, BR produced from the Fria bauxite deposit in Guinea has very high iron contents; 40% of the iron in red mud obtained after digestion of bauxites in the Friguia alumina refinery or 55–60% of the iron in the sands obtained by the gravity method of separation of BR before the thickening and washing step [ 15 ].…”

Section: Introductionmentioning

confidence: 99%

High-Iron Bauxite Residue (Red Mud) Valorization Using Hydrochemical Conversion of Goethite to Magnetite

et al. 2022

Self Cite

View full text Add to dashboard Cite

Bauxite residue (BR), also known as red mud, is a byproduct of the alumina production using the Bayer process. This material is not used to make iron or other iron-containing products worldwide, owing to its high content of sodium oxide and other impurities. In this study, we investigated the hydrochemical conversion of goethite (FeOOH) to magnetite (Fe3O4) in high-iron BR from the Friguia alumina refinery (Guinea) by Fe2+ ions in highly concentrated alkaline media. The simultaneous extraction of Al and Na made it possible to obtain a product containing more than 96% Fe3O4. The results show that the magnetization of Al-goethite and Al-hematite accelerates the dissolution of the Al from the iron mineral solid matrix and from the desilication product (DSP). After ferrous sulfate (FeSO4·7H2O) was added directly at an FeO:Fe2O3 molar ratio of 1:1 at 120 °C for 150 min in solution with the 360 g L−1 Na2O concentration, the alumina extraction ratio reached 96.27% for the coarse bauxite residue size fraction (Sands) and 87.06% for fine BR obtained from red mud. The grade of iron (total iron in the form of iron elements) in the residue can be increased to 69.55% for sands and 58.31% for BR. The solid residues obtained after leaching were studied by XRD, XRF, TG-DTA, VSM, Mössbauer spectroscopy, and SEM to evaluate the conversion and leaching mechanisms, as well as the recovery ratio of Al from various minerals. The iron-rich residues can be used in the steel industry or as a pigment.

show abstract

Section: Introductionmentioning

confidence: 99%

High-Iron Bauxite Residue (Red Mud) Valorization Using Hydrochemical Conversion of Goethite to Magnetite

et al. 2022

Self Cite

View full text Add to dashboard Cite

show abstract

“…The extraction of these elements from BR together with the reduction of its toxicity can be economically and ecologically beneficial. For example, BR produced from the Fria bauxite deposit in Guinea has a very high amount of iron: 40% of the iron in red mud obtained after digestion of bauxites on the Friguia alumina refinery, or 55-60% of the iron in the sands obtained by the gravity method of separation of BR before thickening and washing step [15].…”

Section: Introductionmentioning

confidence: 99%

High-Iron Bauxite Residue (Red Mud) Valorisation Using Hydrochemical Conversion of Goethite to Magnetite

Shoppert¹,

Valeev²,

Diallo³

et al. 2022

Preprint

View full text Add to dashboard Cite

Bauxite residue (BR), also known as red mud, is a by-product of the production of alumina via the Bayer process. Because of the high sodium oxide and other impurities content, this material is not used to obtain iron or other iron-containing products. In this paper, the hydro-chemical conversion of goethite (FeOOH) to magnetite (Fe3O4) in high-iron BR from the Friguia alumina refinery (Guinea) by Fe2+ ions in highly concentrated alkaline media was studied. The simultaneous extraction of Al and Na made it possible to obtain a product containing more than 96% Fe3O4. The results show that the magnetization of Al-goethite and Al-hemetite accelerates the dissolution of the Al from the iron mineral solid matrix and from the desilication product (DSP). After ferrous sulfate (FeSO4·7H2O) was added directly at the FeO:Fe2O3 molar ratio of 1:1 at 120 °C for 150 min in the solution with the 360 g L-1 Na2O concentration, the alumina extraction ratio reached 96.27% for the coarse bauxite residue size fraction (Sands) and 87.06% for fine BR obtained from red mud. The grade of iron (total iron in the form of iron element) in the residue can be increased to 69.55% for Sands and 58.31% for BR. The solid residues obtained after leaching were studied by XRD, XRF, TG-DTA, VSM, Mössbauer spectroscopy and SEM to evaluate the conversion and leaching mechanisms and the recovery ratio of Al from different minerals. The iron-rich residues can be used in the steel industry or as a pigment.

show abstract

Influence of Grain-Size Composition of Bauxite on Its Recovery at Fria Aluminum Plant in Guinea

Cited by 2 publications

References 0 publications

High-Iron Bauxite Residue (Red Mud) Valorization Using Hydrochemical Conversion of Goethite to Magnetite

High-Iron Bauxite Residue (Red Mud) Valorization Using Hydrochemical Conversion of Goethite to Magnetite

High-Iron Bauxite Residue (Red Mud) Valorisation Using Hydrochemical Conversion of Goethite to Magnetite

Contact Info

Product

Resources

About