This study examined hydrogen (H 2 ) and silicon carbide (SiC) as reductants for UG2 chromite pellets to assess their individual and sequential effects on iron (Fe) and chromium (Cr) metallization and the associated carbon (C)‐related off‐gas formation relevant to ferrochrome (FeCr) production. Pellets containing 16–28 wt% SiC were prereduced at 1100°C in H 2 , at 1300°C in N 2 , or sequentially in both atmospheres. At 1100°C, H 2 achieved up to 95.4% Fe metallization and yielded an eskolaite‐type phase. SiC showed little activity below 1300°C, but formed Fe‐ and Cr‐carbides and an Al–Mg–Si‐rich cordierite slag at higher temperatures. Sequential H 2 /SiC reduction improved Cr metallization for pellets with ≤22 wt% SiC (up to 65.7%) as H 2 reduced Fe oxides first, leaving SiC to reduce Cr 2 O 3 . Fe metallization decreased when SiC exceeded 16 wt%, mainly due to pellet densification, which restricted gas diffusion, and the formation of an acidic, silicate‐rich slag that likely reoxidized Fe. Scanning electron microscopy–energy‐dispersive X‐ray spectroscopy analysis showed Fe‐ and Cr‐rich regions within the slag and partially reacted chromite at 1300°C, while limited interaction occurred at 1200°C. A mass balance indicated that sequential H 2 /SiC reduction could theoretically reduce C emissions by up to 75% for the smelting stage. The results indicate that pellet densification and slag acidity must be addressed before industrial application and that the overall emissions benefit depends on the SiC supply pathway.
Coertzen et al. (Sun,) studied this question.