Oil-Dispersed α-Fe<sub>2</sub>O<sub>3</sub> Nanoparticles as a Catalyst for Improving Heavy Oil Oxidation

Mehrabi-Kalajahi, Seyedsaeed; Varfolomeev, Mikhail A.; Rodionov, Nikolay O.; Zinnatullin, Almaz L.; Vagizov, F. G.; Osin, Yuri N.

doi:10.1021/acs.energyfuels.1c00657

Cited by 18 publications

(24 citation statements)

References 58 publications

(110 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The Mössbauer core serves as probe in a solid state. It can be used to study the dynamic properties; structural, valence, and charge states of the Mössbauer atom; the phase composition; and the atomic, crystalline, magnetic, and electronic features of the structure of the studied substance [ 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 ]. Separation into magnetic and non-magnetic components makes it possible to facilitate the analysis of the chemical and phase state of iron in individual fractions of fly ashes, which is enriched by separation [ 15 ].…”

Section: Introductionmentioning

confidence: 99%

Mössbauer Studies of Narrow Fractions of Fly Ash Formed after Combustion of Ekibastuz Coal

et al. 2021

View full text Add to dashboard Cite

Nuclear gamma-resonance spectroscopy on 57Fe nuclei, X-ray diffraction, and scanning electron microscopy have been used to study the narrow fractions of fly ash formed after combustion of the Ekibastuz coal. Two groups of samples of magnetic (ferrospheres) and non-magnetic type have been separated by granulometric and magnetic separation. A number of regularities associated with the granules size of fly ash have been established. According to the data of Mössbauer spectroscopy, a decrease in the magnetically ordered contribution has been identified with the growth of the particle size. After magnetic separation, iron in ferrospheres was found mainly in the structure of Fe3O4/γ-Fe2O3 and α-Fe2O3. The dominant phase was Fe3O4 (60–77%), the amount of which decreases with the growth of the grain size. With the growth of the particle size, the ratio of [Fe]tetra/[Fe]octa positions occupancy in Fe3O4 approaches 0.5; the structure of magnetite tends to the stoichiometric composition. α-Fe was found in the composition of ferrospheres, and a mechanism of its formation was proposed. The main components of the non-magnetic fractions of fly ash are mullite, hercynite, and silicate glass.

show abstract

Section: Introductionmentioning

confidence: 99%

Mössbauer Studies of Narrow Fractions of Fly Ash Formed after Combustion of Ekibastuz Coal

et al. 2021

View full text Add to dashboard Cite

show abstract

“…It contained the following. The internal structures of the device were presented in our earlier works in more detail. ,,,, The heating program of the heater was as follows: RT was increased to 50 °C for 2 min and maintained for 10 min, and then, the heater started to work with a heating rate of 10 °C/min until the temperature of 700 °C. During the reactions, the airflow was equal to 0.5 L/min in the reactor.…”

Section: Methodsmentioning

confidence: 99%

“…The results presented that the presence of copper(II) stearate decreased the oxidation temperature to lower values in both LTO and HTO districts more than nickel(II) stearate and iron(II) stearate. In addition, in our previous works, we reported the addition of oil-soluble and oil-dispersed , catalysts into the heavy oil environment. In our latest studies, we showed that the presence of oil-dispersed , catalysts in heavy oil in both liquid and porous medium due to high-distribution of metal oxides as the active form of catalysts in heavy oil the ignition temperature point, oxidation temperature in both LTO and HTO districts, activation energy of oxidation reaction, and the induction time decreased.…”

Section: Introductionmentioning

confidence: 98%

“…To deal with inaccessible placements or uncommon compositions of unconventional resources, innovative production techniques and novel approaches seem to be necessary. For heavy and extra-heavy oil reservoirs, thermal methods are primarily used methods due to their capability to decrease oil viscosity and increase its mobility. − Generally, thermal EOR (ThEOR) methods consist of steam-assisted gravity drainage, , cyclic steam stimulation, , and in situ combustion (ISC) , methods. However, a literature review on ThEOR methods proposed the ISC technique to be one of the most energy-efficient processes which can improve the properties of heavy oil through decreasing heavy components such as asphaltene and resins. , In the ISC process, air/oxygen is injected into the reservoir to generate heat by burning a portion of the hydrocarbons that leads to a heat front in the reservoir, which reduces the viscosity of heavy and extra-heavy oils and sometimes achieves conditions for in situ upgrading, thereby EOR .…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Oxidation of Heavy Oil Using Oil-Dispersed Transition Metal Acetylacetonate Catalysts for Enhanced Oil Recovery

et al. 2021

Self Cite

View full text Add to dashboard Cite

In this work, several transition metal-based acetylacetonates (Ni, Cu, and Fe) were prepared as oil-dispersed catalysts for heavy oil oxidation. X-ray diffraction (XRD), scanning electron microscopy (SEM), and Mössbauer spectroscopy were used for the characterization of catalysts. The effectivity of catalysts in the oxidation of heavy oil was investigated by a thermogravimetry method coupled with infrared spectroscopy (TG-FTIR) at four different heating rates (4, 6, 8, and 10 °C/min) and self-designed porous medium thermo-effect cell (PMTEC) techniques. The activation energy calculations using three isoconversional methods, Ozawa–Flynn–Wall (OFW), Kissinger–Akahira–Sunose (KAS), and Friedman, were performed based on thermal analysis data. The results showed that the bidentate ligand acetylacetonate (acac) provided good enough distribution of catalysts in heavy oil because in the presence of Cu(acac)2, Fe(acac)3, and Ni(acac)2, the oxidation temperature decreased in both fuel deposition (FD) and high-temperature oxidation (HTO). The activation energy of FD and HTO districts showed that Cu(acac)2 more efficiently catalyzed the oxidation of heavy oil than Fe(acac)3 and Ni(acac)2. The usage of Cu(acac)2 helped decrease the average activation energy of the in situ combustion process from 177 to 117 kJ/mol, from 187 to 127 kJ/mol, and from 198 to 128 kJ/mol based on OFW, KAS, and Friedman methods, respectively. The in situ transformation of the catalysts in the presence of heavy oil was studied under different isothermal conditions. Based on XRD and SEM data at 400 °C, Cu(acac)2 and Ni(acac)2 were transformed to CuO and NiO nanoparticles as the active form of catalysts. For Fe(acac)3, it was found that at 400 °C, it transformed to magnetite (Fe3O4) species; however, at 500 °C, hematite (α-Fe2O3) and maghemite (γ-Fe2O3) were the most predominant species. The heavy oil oxidation using these low-cost and easy to prepare catalysts could be the best route for improving the efficiency of in situ combustion in field applications.

show abstract

“…Mehrabi-Kalajahi et al recently reported in this journal their study on oil-dispersed α-Fe 2 O 3 nanoparticles as a catalyst for improving heavy oil oxidation. While the reported work was carried out certainly with meticulous planning, the analysis and the presentation of the 57 Fe Mössbauer spectroscopic data are erroneous, which constitute the major part of the above study and the conclusions.…”

mentioning

confidence: 99%

Comment on Oil-Dispersed α-Fe₂O₃ Nanoparticles as a Catalyst for Improving Heavy Oil Oxidation

Nayak

2021

Energy Fuels

View full text Add to dashboard Cite

Mehrabi-Kalajahi et al. recently reported in this journal their study on oil-dispersed α-Fe2O3 nanoparticles as a catalyst for improving heavy oil oxidation. While the reported work was carried out certainly with meticulous planning, the analysis and presentation of the 57Fe Mössbauer spectroscopic data are erroneous, which constitute the major part of the above study and the conclusions. They have mentioned that “At 500 °C, two sextets are confirmed as α-Fe2O3 and γ-Fe2O3. The Mössbauer measurements confirm the XRD results and also prove the existence of new components”, but they are completely silent about the detailed observations and the “new components” observed from Mössbauer spectroscopic analysis. Unfortunately, they have not provided the relative abundance of individual iron-bearing phases that can provide a ferrous/ferric ratio, which makes Mössbauer spectroscopy the most powerful tool used for the purpose. They have not clearly mentioned the fitting scheme for these spectra shown in Figure 21 and have not provided the obtained hyperfine parameters (preferably in a tabular form), which are an essential, necessary, and undeclared protocol while presenting the Mössbauer spectroscopic data, prior to its interpretation. In summary, it can be understood that, although the choice of techniques was excellent considering the great potential of Mössbauer spectroscopy, especially for these types of studies, the inability to extract a great deal of information from the carefully obtained Mössbauer spectra make the study and its subsequent discussion of not much use.

show abstract

Oil-Dispersed α-Fe₂O₃ Nanoparticles as a Catalyst for Improving Heavy Oil Oxidation

Cited by 18 publications

References 58 publications

Mössbauer Studies of Narrow Fractions of Fly Ash Formed after Combustion of Ekibastuz Coal

Mössbauer Studies of Narrow Fractions of Fly Ash Formed after Combustion of Ekibastuz Coal

Oxidation of Heavy Oil Using Oil-Dispersed Transition Metal Acetylacetonate Catalysts for Enhanced Oil Recovery

Comment on Oil-Dispersed α-Fe₂O₃ Nanoparticles as a Catalyst for Improving Heavy Oil Oxidation

Contact Info

Product

Resources

About

Oil-Dispersed α-Fe2O3 Nanoparticles as a Catalyst for Improving Heavy Oil Oxidation

Cited by 18 publications

References 58 publications

Mössbauer Studies of Narrow Fractions of Fly Ash Formed after Combustion of Ekibastuz Coal

Mössbauer Studies of Narrow Fractions of Fly Ash Formed after Combustion of Ekibastuz Coal

Oxidation of Heavy Oil Using Oil-Dispersed Transition Metal Acetylacetonate Catalysts for Enhanced Oil Recovery

Comment on Oil-Dispersed α-Fe2O3 Nanoparticles as a Catalyst for Improving Heavy Oil Oxidation

Contact Info

Product

Resources

About

Oil-Dispersed α-Fe₂O₃ Nanoparticles as a Catalyst for Improving Heavy Oil Oxidation

Comment on Oil-Dispersed α-Fe₂O₃ Nanoparticles as a Catalyst for Improving Heavy Oil Oxidation