Influence of Cerium on the Reduction Behaviour of Iron Oxide by Using Carbon Monoxide: TPR and Kinetic Studies

Reduction of iron oxide is one of the most studied topics owing to the importance of iron/steel industry and also has been used as a precursor and active component in a number of important chemical processes. The interaction between iron oxide and other metal additive have gained interest in the past two decades due to the ability on enhancing the reduction performance of the iron oxide. Therefore, this study was undertaken to investigate the influence of cerium on the reduction behaviours of iron oxide by (10%, v/v) carbon monoxide in nitrogen. The cerium doped (Ce-Fe2O3) and non-doped iron oxide reduction behaviour and the kinetic studies have been studied by temperature programmed reduction (TPR) and the phases formed of partially and completely reduced samples were characterized by X-ray diffraction spectroscopy (XRD) while the activation energy values were calculated from Arrhenius equation using Wimmer’s method. TPR results indicate that the reduction of doped and undoped iron oxide proceeds in three steps reduction (Fe2O3 ? Fe3O4 ? FeO ? Fe), while doped iron oxide showed a large shifted towards lower temperature especially in the transition steps of FeO ? Fe. Furthermore, TPR results also suggested that by adding Ce metal into iron oxide the reduction of metal iron completed at lower temperature (700 ?C) compared to non-doped iron oxide (900 ?C). Meanwhile, XRD analysis indicated that doped iron oxide composed of Fe2O3 and a small amount of FeCe2O4. The increase in the rates of iron oxide reduction may relate to the presence of cerium species in the formed of FeCe2O4 and was confirmed by the decrease in the activation energy regarding to all transition phases (Fe2O3 ? Fe3O4 ? FeO ? Fe) during the reduction process

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The Reduction Behaviour of Cerium Doped Iron Oxide in Hydrogen and Carbon Monoxide Atmosphere

Materials Science Forum ◽

10.4028/www.scientific.net/msf.840.381 ◽

2016 ◽

Vol 840 ◽

pp. 381-385

Author(s):

Tengku Shafazila Tengku Saharuddin ◽

Alinda Samsuri ◽

Fairous Salleh ◽

Rizafizah Othaman ◽

Mohammad Kassim ◽

...

Keyword(s):

Carbon Monoxide ◽

Iron Oxide ◽

Metallic Iron ◽

Reduction Process ◽

Xrd Analysis ◽

Temperature Programmed Reduction ◽

X Ray Diffraction ◽

X Ray ◽

Reduction Behaviour ◽

Temperature Programmed

The reduction behaviour of 3% cerium doped (Ce-Fe2O3) and undoped iron oxide (Fe2O3) by hydrogen in nitrogen (10%,v/v) and carbon monoxide in nitrogen (10%,v/v) atmospheres have been investigate by temperature programmed reduction (TPR). The phases formed of partially and completely reduced samples were characterized by X-ray diffraction spectroscopy (XRD). TPR results indicate that the reduction of Ce doped and undoped iron oxide in both reductants proceed in three steps reduction (Fe2O3 → Fe3O4 → FeO → Fe) with Fe3O4 and FeO were the intermediate. TPR results also suggested that by adding Ce metal into iron oxide the reduction to metallic Fe by using both reductant gaseous give better reducibility compare to the undoped Fe2O3. The reduction process of Ce and undoped Fe2O3 become faster when CO was used as a reductant instead of H2. Furthermore, in CO atmosphere, Ce-Fe2O3 give complete reduction to metallic iron at 700 0C which about 200 0C temperature lower than other samples. Meanwhile, XRD analysis indicated that Ce doped iron oxide composed better crystallite phases of Fe2O3 with higher intensity and a small amount of FeCe2O4.

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Effect of Cobalt on Nickel Oxide Toward Reduction Behaviour in Hydrogen and Carbon Monoxide Atmosphere

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1010.373 ◽

2020 ◽

Vol 1010 ◽

pp. 373-378

Author(s):

Norliza Dzakaria ◽

Maratun Najiha Abu Tahari ◽

Salma Samidin ◽

Tengku Shafazila Tengku Saharuddin ◽

Fairous Salleh ◽

...

Keyword(s):

Carbon Monoxide ◽

Nickel Oxide ◽

Reduction Process ◽

Xrd Analysis ◽

X Ray Diffraction ◽

X Ray ◽

Reduction Behaviour ◽

One Step ◽

Temperature Programmed ◽

Co Doped

The reduction behaviour of cobalt doped with nickel oxide and undoped nickel oxide (NiO) by hydrogen (H2) in nitrogen (20%, v/v) and carbon monoxide (CO) in nitrogen (40%, v/v) atmospheres have been investigated by temperature programmed reduction (TPR). The phases formed of partially and completely reduced samples were characterized by X-ray diffraction spectroscopy (XRD). TPR results indicate that the reduction of Co doped and undoped nickel oxide in both reductants proceed in one step reduction (NiO → Ni) without intermediate. TPR results also suggested that by adding Co metal into NiO, the reduction to metallic Ni by both reductant gaseous give different intensity of the peak. The reduction process of Co and undoped NiO become faster when H2 was used as a reductant. Furthermore, in H2 atmosphere, Co-NiO give complete reduction to metallic Ni at 700 °C. Meanwhile, XRD analysis indicated that NiO without Co composed better crystallite phases of NiO with higher intensity.

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Analysis of Iron Oxide Reduction Kinetics in the Nanometric Scale Using Hydrogen

Nanomaterials ◽

10.3390/nano10071276 ◽

2020 ◽

Vol 10 (7) ◽

pp. 1276 ◽

Cited By ~ 1

Author(s):

Swathi K. Manchili ◽

Johan Wendel ◽

Eduard Hryha ◽

Lars Nyborg

Keyword(s):

Activation Energy ◽

Iron Oxide ◽

Reaction Kinetics ◽

Reduction Process ◽

Steel Powder ◽

Surface Oxide ◽

Oxide Reduction ◽

Sintering Aid ◽

Surface Iron ◽

Reported Data

Iron nanopowder could be used as a sintering aid to water-atomised steel powder to improve the sintered density of metallurgical (PM) compacts. For the sintering process to be efficient, the inevitable surface oxide on the nanopowder must be reduced at least in part to facilitate its sintering aid effect. While appreciable research has been conducted in the domain of oxide reduction of the normal ferrous powder, the same cannot be said about the nanometric counterpart. The reaction kinetics for the reduction of surface oxide of iron nanopowder in hydrogen was therefore investigated using nonisothermal thermogravimetric (TG) measurements. The activation energy values were determined from the TG data using both isoconversional Kissinger–Akahira–Sunose (KAS) method and the Kissinger approach. The values obtained were well within the range of reported data. The reaction kinetics of Fe2O3 as a reference material was also depicted and the reduction of this oxide proceeds in two sequential stages. The first stage corresponds to the reduction of Fe2O3 to Fe3O4, while the second stage corresponds to a complete reduction of oxide to metallic Fe. The activation energy variation over the reduction process was observed and a model was proposed to understand the reduction of surface iron oxide of iron nanopowder.

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The potential of coal gasification in a novel iron oxide reduction process

Chemical Engineering Science ◽

10.1016/0009-2509(90)80163-9 ◽

1990 ◽

Vol 45 (8) ◽

pp. 2721-2728 ◽

Cited By ~ 3

Author(s):

M. Weeda ◽

P.J.J. Tromp ◽

J.A. Moulijn

Keyword(s):

Iron Oxide ◽

Coal Gasification ◽

Reduction Process ◽

Oxide Reduction ◽

Iron Oxide Reduction

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Effect of Noble Metal Silver on the Reduction Behaviour of Molybdenum Oxide Using Carbon Monoxide

Materials Science Forum ◽

10.4028/www.scientific.net/msf.888.377 ◽

2017 ◽

Vol 888 ◽

pp. 377-381

Author(s):

Alinda Samsuri ◽

Fairous Salleh ◽

Tengku Shafazila Tengku Saharuddin ◽

Rizafizah Othaman ◽

Mohamed Wahab Mohamed Hisham ◽

...

Keyword(s):

Carbon Monoxide ◽

Molybdenum Trioxide ◽

Reduction Process ◽

Reduction Peak ◽

X Ray Diffraction ◽

Reduction Behavior ◽

X Ray ◽

Reduction Behaviour ◽

Temperature Programmed ◽

Lower Temperature

The reduction behavior of silver doped molybdenum trioxide (Ag/MoO3) and undoped MoO3 by using carbon monoxide, CO were investigated by using temperature programmed reduction (TPR). The reduced phases were characterized by X-ray diffraction (XRD). In the carbon monoxide atmosphere, the XRD results indicated that the reduction of Ag/MoO3 and undoped MoO3 to MoO2 phase proceed in two steps (MoO3 → Mo4O11 → MoO2) with Mo4O11 present as an intermediate state. A complete reduction to metallic molybdenum for both samples cannot occurred since in an excess CO atmosphere, MoO2 is promoted to form carbides rather than reduce to metallic molybdenum. Nevertheless, addition of silver to modified MoO3 shows the better reducibility compared to MoO3 alone by lower the reducing temperature of MoO3. TPR results show that the reduction peak of Ag/MoO3 is slightly shifts to lower temperature as compared with the undoped MoO3. The interaction between silver and molybdenum ions leads to this slightly decrease of the reduction temperature of silver doped MoO3. It can be seen that doping with silver has a remarkable influence in the reduction process of the MoO3 catalyst.

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