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Abstract  

Iron and boron species in the products of thermit reaction of aluminum, iron oxide, and boron oxide were characterized by Mössbauer spectroscopy, X-ray diffraction, and prompt γ-ray analysis. It was revealed that iron and boron products of the thermit reaction are composed of intermetallic compounds with aluminum.

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Abstract  

Wellhead equipment corrosion samples including internal surface of choke were analyzed by means of Mössbauer spectroscopy and X-ray diffractometry. The samples include some impurities of quartz, dolomite and calcite. The resulted analysis shows some iron oxides and oxyhydroxides as surface equipment corrosion products.

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Abstract  

Phthalocyanineiron/II/ in NaY zeolite was synthesized via various processes from an iron carbonyl compound into NaY zeolite in gaseous phase. Mössbauer spectra of the final product /phthalocyanineiron/II// and the precursor species /iron oxide and [phthalocyaninato/2-/]bis/pyridine/iron/II// in NaY zeolite were measured to characterize the chemical and physical states of the iron species.

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Abstract  

The effect of organic matter and iron oxides as solid components of the red earth on the retention of SeO3 has been investigated by a batch technique and selective extraction method. The sorption and desorption isotherms of SeO3 on the untreated red earth and the three treated soils were determined at 20°C, pH 6.8 or 7.2 and in the presence of 0.01M CaCl2. It was found that the sorption-desorption hysteresis for untreated an treated soils is obvious and the clays play an important role in the sorption-desorption hysteresis, and that the retention of SeO3 on red earth is attributed to the iron oxides to a great extent.

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Journal of Thermal Analysis and Calorimetry
Authors: Ana Brăileanu, M. Răileanu, M. Crişan, D. Crişan, R. Bîrjega, V. Marinescu, J. Madarász, and G. Pokol

Abstract  

Two series of nanocomposites from the FexOy–SiO2 system, containing 20 mass% iron oxide were prepared by the alkoxide route of the sol–gel method, in the absence and presence of catalyst. The silica gel has been obtained using tetraethoxysilane. The iron(III) nitrate nonahydrate has been used as iron oxides source. The samples have been prepared in identical conditions, differing only by the gelation times, induced by different surface of evaporation/volume (S/V) ratios of sol let to gelify. Thermal analysis data have established the thermal treatments conditions of the prepared samples and were correlated with X-ray diffraction, IR spectroscopy and TEM results, in order to accomplish a complete structural characterization. The correlation between the structural modifications of the FexOy–SiO2 nanocomposites and different conditions of drying has been established.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: G. Lujanienė, S. Meleshevych, V. Kanibolotskyy, J. Šapolaitė, V. Strelko, V. Remeikis, O. Oleksienko, K. Ribokaitė, and T. Ščiglo

Abstract  

A sorption ability of titanium silicates (TiSi) and iron oxides towards Cs, Sr, Pu and Am was tested using the laboratory batch method. The obtained results are expressed as distribution coefficients (Kd). TiSi synthesised using TiOSO4 revealed better sorption ability towards all studied radionuclides in comparison with TiSi produced on the basis of TiCl4. The Kd values ranged from 3.9 × 102 to 1.6 × 105 mL g−1 for Sr, from 6 to 4.1 × 104 mL g−1 for Cs, from 2.2 × 102 to 2.6 × 105 mL g−1 for Pu and from 50 to 1.6 × 104 mL g−1 for Am. The highest Pu Kd values (9 × 103–6.2 × 104 mL g−1) and better kinetics were found for iron oxides.

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Abstract  

The batch method and the column method were simultaneously employed to study the sorption and desorption of Eu(III) on red earth as a function of pH (4.6–6), the presence of a well-characterized fulvic acid (FA) and the iron oxides content of red earth. The results from both methods were consistent qualitatively. The Eu(III) sorption showed significant dependences on pH and FA, the sorption was increased with increasing pH and by addition of FA to the solutions, while the iron oxides content of the red earth had a negative contribution to the sorption of Eu(III). Additionally, the sorption-desorption hysteresis of Eu(III) on red earth occurred at a pH range of 4.6–6. Therefore, the humic substance and high pH have a great tendency to immobilize Eu(III) on red earth.

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Abstract  

The phase analysis of the rusts generated beneath the primer containing micaceous iron oxide (MIO) and micaceous iron oxide in combination with red lead (RL), zinc phosphate (ZP), basic lead silicochromate (BLSC) and zinc chromate (ZC) has been carried out by Mössbauer spectroscopy at room temperature. The rust beneath the coating obtained after immersion of the painted panel for six months in 3% NaCl, consists mainly of nonstoichiometric magnetite together with small fractions of γ-, α-FeOOH except in the case of panel painted with RL containing MIO showed only a central doublet indicating the formation of γ-FeOOH and SPM α-FeOOH. Non-stoichiometry of magnetite as calculated from the ratio of B/A sites of the peaks of magnetite in the spectrum has been found depending on the nature of anticorrosive pigment present in the primer coating. The order of non-stoichiometry has been found to be in order of ZC>BLSC>ZP>MIO.

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Abstract  

The effects of temperature (373–1373 K) on the point of zero charge (PZC) and isoelectric point (IEP) of a red soil rich in kaolinite and iron minerals were studied. PZC values of the soil treated at 373 and 573 K indicated the presence of iron oxide. The soil calcined between 773 and 1173 K shows a PZC almost coincident with the respective values of kaolinite. At 1373 K, the PZC of the soil is nearer to the value of iron oxide. In the entire temperature range studied the PZC values were lower than the IEP values. An approach of PZC and IEP values was observed after a partial removal of iron oxide by the dithionite-citrate-bicarbonate (DCB) method. The analyses of the PZC and IEP values, of electron probe micro analysis (EPMA) data and of specific surface areas evidence a specific adsorption of iron oxide on kaolinite. Finally, the dissolution sequence of iron and aluminium contained in soil was determined using hydrochloric acid.

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Abstract  

This paper present results of research performed on briquettes containing iron oxides with the aiming of establishing a relationship between their chemical and phase compositions. Briquettes obtained from industrial in-plant fines waste were subjected to experimental tests involving simulation of the temperature conditions and the redox potential of a gas phase, characteristic of both the top and central parts of a blast furnace. The results of the analysis allowed conclusions concerning the use of briquettes as a blast furnace charge component.

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