DOE OSTI · 3393978
Iron Oxide Reduction Rate Affects Iron Product Morphology
Abstract
Magnetite concentrates from different parts of the Mesabi Range, exhibiting varying tendencies to encapsulate, were reduced using thermogravimetric analysis (TGA) and a high-temperature confocal scanning laser microscope (CSLM). Gas-phase mass-transfer conditions were intentionally varied by employing two reactors with different geometries: the TGA produced significantly slower reduction, whereas the CSLM setup yielded reduction rates up to 20 times faster under mass-transfer-controlled conditions. A preliminary mechanism is proposed to explain the transition from a porous iron product to a dense encapsulating layer. Encapsulation is interpreted as the outcome of competition between pore creation, driven by the reduction rate, and pore elimination, driven by surface diffusion. When pore formation is insufficient to counteract pore coarsening, a dense iron layer develops and restricts further reduction.
Explore related subjects
Keep this discovery
Explore connections, maps & timelines
Rapalo, Rafaela [Carnegie Mellon Univ., Pittsburgh, PA (United States)], Pistorius, Petrus Christiaan [Carnegie Mellon Univ., Pittsburgh, PA (United States)] (ORCID:0000000229661879). 2026-06-29. Iron Oxide Reduction Rate Affects Iron Product Morphology. https://doi.org/10.1007/s11669-026-01262-2
Cite the original work for its findings. Save a collection to share your selection of sources.