H2PlasmaRed published the 7th peer-reviewed publication: Hematite Leach Residue as a Material for Hydrogen Plasma Smelting Reduction: A Laboratory-Scale Study on Chemical Composition and Optical Emissions

We’re pleased to share H2PlasmaRed Horizon Europe’s seventh peer reviewed article publication by Henna-Riikka Putaala, Henri Pauna, Areej Javed, Ubaid Manzoor, Dennis Klapproth, Ville-Valtteri Visuri, Annelies Malfliet, Rita Kallio, Isnaldi Souza Filho, Mari Lindgren, Dierk Raabe and Timo Fabritius in Metallurgical and Materials Transactions B: Hematite Leach Residue as a Material for Hydrogen Plasma Smelting Reduction: A Laboratory-Scale Study on Chemical Composition and Optical Emissions.

In this study, the suitability of hematite leach residue – a sidestream material – for hydrogen plasma smelting reduction (HPSR) was investigated, and the process was monitored with in-situ optical emission spectroscopy (OES). Leach residue was found to be a suitable material for HPSR, with 87 % theoretical metallization degree achieved after 10 minutes of reduction, although some Fe was lost to evaporation. In addition to wüstite, two spinel phases were found in the slag phase. As Fe reduced, elements such as Al and Mg enriched in the slag and their respective optical emissions increased, indicating higher evaporation of these elements.

The findings support the use of hematite leach residue in HPSR and demonstrate the connection between the changes in chemical composition and optical emissions, which can possibly be utilized when scaling up the process.

Link to full paper: https://link.springer.com/article/10.1007/s11663-026-04099-9