Studies on CO₂ Adsorption and Desorption Properties from Various Types of Iron Oxides (FeO, Fe₂O₃, and Fe₃O₄)

Abstract

Various type iron oxides of FeO, Fe2O3, and Fe3O4 were used for carbon dioxide (CO2) capture at room temperature and pressure by studying its adsorption–desorption properties. Several interactions of carbonate species were detected on its surface. The morphology of carbonate formation shows different structures on FeO (grooves-like), Fe2O3 (fine sharp particles), and Fe3O4 (aggregated nanoparticles). CO2 chemisorption discovered a potential adsorbent of Fe2O3 with an adsorption capacity of 3.95 mgCO2/gadsorbent. The adsorption capacity increased up to 62.8% by using concentrated 99.9% CO2 for adsorption. At higher concentration of CO2 exposure, it partially turns to red color which indicated the less stable Fe3O4 was easily oxidized to Fe2O3 after CO2 regeneration with temperatures up to 500 °C. Hence, Fe2O3 possessed the highest basicity strength (1.26 cm3/g), and the adsorption capacity after four cycles was not significantly reduced by 8.6% indicating an effective chemical or physical adsorption in CO2 capture.

Atomic‐Scale Studies of Fe3O4(001) and TiO2(110) Surfaces Following Immersion in CO2‐Acidified Water

“…[31,32,33,34] As the pH is decreased to 4.0 and to 3.9, a peak at 289.9 eV appears, indicating the presence of a surface bicarbonate (HCO 3 À ) species. [31][32][33]35] In addition, we observe a small feature at lower binding energy (281.5 eV) which is 8.4 eV apart from the main bicarbonate peak. This corresponds to the spacing between the α 1,2 and the α 3 lines of the Mg anode, and therefore the peak can be attributed to an x-ray satellite of the α 1,2 signal at 289.9 eV.…”

Directly converting CO2 into a gasoline fuel

“…Furthermore, density functional theory calculations have demonstrated that Fe 3 O 4 (111) surface is very capable of activating CO 2 (refs 20, 21). Typically, iron catalysts need alkali metal promotion to attain desired activity and selectivity.…”

A multi-technique study of CO2 adsorption on Fe3O4 magnetite

“…14 To date there are no investigations of CO 2 adsorption on well-defined iron-oxide surfaces, despite the important role of these materials in both geochemistry and catalysis. Work on polycrystalline Fe 3 O 4 , 15 Fe 3 O 4 nanoparticles, 16 and FeO x nanoclusters on graphite 17 suggests however that both physisorption and carbonate formation can a) E-mail address: parkinson@iap.tuwien.ac.at occur, with stronger binding linked to the presence of Fe 2+ cations. 18,19 Very recent density functional theory (DFT) calculations based on the Fe 3 O 4 (111) surface suggest that CO 2 chemisorption can occur at undercoordinated oxygen sites and that this surface can activate CO 2 for hydrogenation.…”