Revealing Multi-Scale Mechanism of Hydrogen-Based Direct Iron Reduction: A Ptychotomographic Analysis

The hydrogen direct iron reduction (DIR) process is a nearly carbon-free new ironmaking strategy, but its scalability is limited by complex endothermic chemistry that mitigates its yield. This paper studies the multi-scale mechanism of hydrogen-based DIR to quantify the multi-scale dynamics that mitigate efficiency in DIR. Using ptycho-tomographic imaging, 3D maps of magnetite fines are measured as they are reduced, observing elongated structures that form during reduction. It is demonstrated that the kinetics are hindered by mass transport limitations from sintering before the reaction completes. The results demonstrate a new tool for process optimization for DIR.

Subhechchha Paul | Stanford University
 

Leora Dresselhaus-Marais | Stanford University
 

Subhechchha Paul | Stanford University
 

Dr. Xueli (Sherry) Zheng | Stanford University