An iron ore-based catalyst for producing hydrogen and metallurgical carbon via catalytic methane pyrolysis for decarbonisation of the steel industry

Experiments to investigate the catalytic pyrolysis of methane using an iron ore-based catalyst were carried out to optimize catalytic activity and examine the purity of the car-bon produced from the process for the first time. Ball milling of the iron ore at 300 rpm for varying times -from 30 to 330 min -was studied to determine the effect of milling time on methane conversion. Optimal milling for 270 min led to a five-fold increase in methane conversion from ca. 1%-5%. Further grinding resulted in a decline of methane conversion to 4% shown by SEM to correspond to an increase in particle size caused by agglomeration. Data from Raman and Moeurossbauer spectroscopy and H2 temperature programmed reduc-tion indicated a change in phase from magnetite to maghemite and hematite (at the par-ticle surface) as the grinding time increased. Analysis of the carbon produced as a byproduct of the reaction indicated a highly pure material with the potential to be used as an additive for steel production.& COPY; 2023 The Authors. Published by Elsevier Ltd on behalf of Hydrogen Energy Publications LLC. This is an open access article under the CC BY license (http://creativecommons.org/ licenses/by/4.0/).

Automated summary

Experiments on the catalytic pyrolysis of methane using an iron ore-based catalyst were conducted to optimize catalytic activity and examine the purity of the carbon produced. The effect of ball milling the iron ore for different times (from 30 to 330 min) at 300 rpm on methane conversion was studied. Optimal milling for 270 min resulted in a significant increase in methane conversion to 5%, but further grinding led to a decline in conversion to 4% due to particle agglomeration.