Work

Rapid, efficient reduction of iron oxide with ammonia

Year: 2025

Type: article

Abstract: Reducing iron oxide to iron metal with fossil fuels produces circa 4% of annual anthropogenic CO 2 , ca. 2 Gt/a, as direct chemical emissions from the process. Using ammonia instead of coke—releasing only water and nitrogen as byproducts—could be a widely deployable method of decarbonizing industrial ironmaking, because ammonia carries hydrogen and can be transported easily worldwide. However, initial reports suggest that the reaction of ammonia with iron oxide is slow and inefficient, completed only in hours and using only a few percent of the ammonia supplied. Drawing on thermodynamic and kinetic analysis of the reaction, we explored high-temperature, high-flow reaction conditions designed to increase the reaction rate and the ammonia utilization. We report the reduction of iron oxide in 1 min while using 64% of the ammonia supplied. We show that these insights translate to the gram scale and the reduction of pelletized ore, a common form used industrially.

Source: Cell Reports Physical Science

DOI: 10.1016/j.xcrp.2025.102551

Authors: Sanya Mittal, Luke M. Davis

Institution: Tufts University

Language: English

Topic: Iron and Steelmaking Processes

Subfield: Mechanical Engineering

Field: Engineering

Domain: Physical Sciences

SDGs: Climate action, Responsible consumption and production

Open Access status: gold

Estimated APC paid: $5,620