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Extraction of Aluminum and Iron from Bauxite: A Unique Closed-Loop Ore Refining Process Utilizing Oxalate Chemistry
  • Ankit Verma,
  • David Corbin,
  • Mark Shiflett
Ankit Verma
University of Kansas School of Engineering

Corresponding Author:[email protected]

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David Corbin
University of Kansas School of Engineering
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Mark Shiflett
University of Kansas School of Engineering
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The Bayer process holds an exclusive status for alumina extraction, but a massive amount of caustic “red mud” waste is generated. In this work, three oxalate reagents: potassium hydrogen oxalate (KHC2O4), potassium tetraoxalate (KHC2O4·H2C2O4), and oxalic acid (H2C2O4) were investigated for the Al and Fe extraction process from NIST SRM 600 – Australian Darling range bauxite ore. More than 90% of Al and Fe was extracted into the aqueous phase in less than 2 h with 0.50 M C2O42- for all three reagents. The Fe and Al can be selectively precipitated by hydrolyzing the aqueous phase. By acidifying the Al and Fe free filtrate, 80% of the C2O42- can be precipitated as KHC2O4·H2C2O4. Greater than 90% of the aqueous acid can also be recycled using a cation exchange resin. The proposed closed-loop process is an energy-efficient, cost-effective, environmentally-friendly route for extracting Al and Fe from bauxite ore.
22 May 2021Submitted to AIChE Journal
31 May 2021Submission Checks Completed
31 May 2021Assigned to Editor
13 Jun 2021Reviewer(s) Assigned
15 Aug 2021Editorial Decision: Revise Major
24 Aug 20211st Revision Received
28 Aug 2021Submission Checks Completed
28 Aug 2021Assigned to Editor
29 Aug 2021Reviewer(s) Assigned
22 Sep 2021Editorial Decision: Accept
Feb 2022Published in AIChE Journal volume 68 issue 2. 10.1002/aic.17477