Mechanism of Redox Surface Reaction between Wüstite and CO2 or CO

Abstract

The redox reaction between thin wüstite foil and CO2 or CO was studied by means of a microbalance in a temperature range 900–1075°C. It was found that the reaction at the gas-wüstite interface is rate-controlling and that the reaction rate is expressed as V_ox=k_OP_CO2a_O^-m/3 and V_red=k_O’P_COa_O^n/3 where aO is the oxygen activity of wüstite, and m and n are 2.1–2.2 and 0.8–1.2, respectively. On the basis of the theory by Kobayashi and Wagner, the most predominant mechanism is concluded to be CO_2+2\ominus\ightleftarrowsCO+O^2- Actigation energies for kO and kO′ were 35+3 and 32+3 kcal/mol, respectively.

Production of Carbon from Carbon Dioxide with Iron Oxides and High-Temperature Solar Energy

“…One can also cite others who studied the metal oxide carbon system, but the motivation of this earlier work had been to optimize the metal-forming reaction. [13][14][15][16][17] Our work focuses on using iron oxides to produce carbon from CO 2 . Here, only a few studies can be cited.…”

“…It is therefore evident that one can cite experimental work with respect to the solar step for C(gr) production. One can also cite others who studied the metal oxide carbon system, but the motivation of this earlier work had been to optimize the metal-forming reaction. − Our work focuses on using iron oxides to produce carbon from CO 2 . Here, only a few studies can be cited.…”