2026-09-22T03:12:51Z https://www.ideals.illinois.edu/oai-pmh

oai:www.ideals.illinois.edu:2142/127295 2025-03-29 col_2142_5131 col_2142_13836 com_2142_5130 com_2142_13835 com_2142_234

application/pdf en text Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2025-03-28 without embargo terms The student, Jazline Rebollar, accepted the attached license on 2024-12-11 at 15:45. The student, Jazline Rebollar, submitted this Thesis for approval on 2024-12-11 at 17:21. This Thesis was approved for publication on 2024-12-13 at 11:02. DSpace SAF Submission Ingestion Package generated from Vireo submission #21575 on 2025-03-28 at 14:28:46 Materials characterization of reduced iron oxide samples and atmospheric H2 plasma assisted reduction at low temperatures Rebollar, Jazline 2024-12-13 Krogstad, Jessica Iron Oxide Reduction eng The steel industry is a cornerstone of global manufacturing. Its projection for growth is evident both in its production scale and its significant environmental footprint, making it a critical sector for sustainability efforts. An emerging route to reducing iron oxide is using Hydrogen (H2) as a reducing agent. Reduction of iron oxide using H2 plasma can streamline the modernization of steel production while simultaneously decreasing carbon emissions to the atmosphere. Though there is research on the reduction kinetics of iron oxide at the macroscale, less is known about the microscale where nuances between reducing agents are expected to be most critical. Understanding the reduction mechanisms at the microscale can give insight into the transport and reaction kinetics, consequently enabling designs and optimizing processing conditions. In this work, an H2 plasma reactor is used to reduce iron oxide pellets, films, and iron ore powders. Optimal plasma parameters are determined by macroscopic quantifications like mass loss and X-ray diffraction (XRD). In industrial pellets and iron ore powders, porosity increases with reduction. Therefore, microstructural evolution was carefully observed pre- and post-reduction to determine whether it could be used as an indicator of the reduction of iron oxide in parallel to bulk characterization. We observed similar microstructural evolution during the reduction of samples using hydrogen plasma at low temperatures and shorter reduction times, comparable to findings from the literature on pure hydrogen reduction at higher temperatures. Because plasma parameters are interdependent, varying them can affect the reduction of iron oxide to pure iron; we can confirm that microwave hydrogen plasma reduces iron oxide. 2024-12 Thesis https://hdl.handle.net/2142/127295 Copyright 2024 Jazline Rebollar Materials Science & Engineerng Materials Science & Engr University of Illinois at Urbana-Champaign M.S. Thesis