A new application of the commercial high temperature water gas shift catalyst for reduction of CO2 emissions in the iron and steel industry: Lab-scale catalyst evaluation

In this study, we present a detailed investigation of a commercial iron-based high temperature water gas shift (HTWGS) catalyst (Johnson Matthey KATALCOTM 71-6) in a new application: the production of hydrogen from blast furnace gas (BFG), which originates from iron and steel manufacturing. During the lab-scale catalytic testing under BFG conditions the catalyst demonstrated: 1) high water gas shift activity and stability; 2) minimal methanation at reduced steam to CO ratios; 3) high resistance towards H2S impurities present in the feed. The results of post-characterization of the discharged samples confirm the robustness of KATALCO 71-6 towards BFG process conditions: no over-reduction of the catalytically active Fe3O4 phase and no formation of a less active FeS phase. An in situ X-ray absorption spectroscopy study revealed no over-reduction of the iron phase under BFG conditions and the stabilization of the iron phase by diffusion of chromium into the iron oxide matrix. The findings of this study demonstrate the suitability of the iron-based HTWGS catalyst KATALCO 71-6 for the production of hydrogen from BFG streams. Knowledge gained in this study is an essential step in the development and scale up of carbon capture and storage as well as carbon capture and utilization technologies, such as the sorption enhanced water gas shift (SEWGS) technology, aimed at reducing the CO2 footprint during steel manufacturing.