Thermal behavior and evolution of the mineral phases of Brazilian red mud

Mercury, José Manuel Rivas; Cabral, Aluísio A.; Paiva, António; Angélica, Rômulo Simões; Neves, R. F.; Scheller, Thomas

doi:10.1007/s10973-010-1039-7

Cited by 37 publications

(23 citation statements)

References 30 publications

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“…In general, the minerals that are present in the sample of red mud, can be identify and classify in two categories. In the first, phases from bauxite such as gibbsite, hematite, goethite, anatase and quartz; this results are similar to those reported by Rivas Mercury et al 31 . The second category, phases formed during Bayer process such as sodalite and cancrinite 29 .…”

supporting

confidence: 90%

Application of bauxite waste from amazon region in the heavy clay industry

et al. 2013

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In this work, a method was developed for the application of red mud, an alkaline leaching waste, from a bauxite processing plant located in northern Brazil (Amazon region) as starting material for heavy clay products. Samples were prepared by pressing blends of red mud and clay, which were then fired at temperatures from 900 °C to 1190 °C. Characterization was carried out by chemical analysis, differential thermal analysis (DTA) and X-ray diffraction (XRD), and the following ceramic properties were evaluated: water absorption, linear shrinkage and flexural strength. In order to evaluate the Na + stability in the dense ceramic, leaching tests were also carried out on the specimens after sintering process. Results indicated that samples with 50 and 70 wt% of red mud are proper for being used in the production of ceramic bodies, due to its excellent properties, mainly high mechanical resistance and low water absorption, showing thus, an option to minimizing the environmental impacts caused by the aluminum industry.

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confidence: 90%

Application of bauxite waste from amazon region in the heavy clay industry

et al. 2013

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“…These results are in good agreement with the literature about red mud 7 . The mineralogy of the red mud was analyzed by XRD and it complies with the literature 7,15 . In the XRD patterns of red mud given in Figure 3, it can be observed peaks corresponding to sodalite (NaAlSi 4 Figure 4 shows the average current density, ρ i , as a function of treatment time.…”

Section: Red Mud Characterizationmentioning

confidence: 85%

Thin films produced on 5052 aluminum alloy by plasma electrolytic oxydation with Red Mud-containing Electrolytes

et al. 2014

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“…Although the overall course of the processes is widely known, the effects of various crystal-chemical and chemical factors on the transformation mechanisms and properties of the products are still under vigorous debate [1,3]. This type of research focuses usually on monomineral synthetic samples [e.g., [4][5][6][7][8][9][10] and does not fully reflect the complexity of the processes during thermal transformations of natural Fe-oxide-rich materials [e.g., [10][11][12][13][14][15][16][17], archeological findings [18,19] and composite industrial products or wastes [20][21][22]. A good example of such a complex system are bog iron ores.…”

Section: Introductionmentioning

confidence: 99%

Mineral transformations and textural evolution during roasting of bog iron ores

Rzepa

Bajda

Gaweł

et al. 2015

J Therm Anal Calorim

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The processes occurring during roasting of bog iron ores were characterized using TG-DTG-DTA-QMS, XRD, FTIR and specific surface analysis. Removal of physically adsorbed water is followed by dehydroxylation of iron oxyhydroxides and oxidation of organic matter at 200-600°C. The main product of the transformations is disordered nanocrystalline (proto)hematite or hematite/-maghemite mixture, depending on organic matter content and heating conditions. The conversion of iron oxyhydroxides to hematite occurs at temperatures different than those reported for pure compounds. At higher temperatures, protohematite undergoes recrystallization to the stoichiometric hematite, and manganese oxides are partially reduced. At 1000°C, the roasting products consist of hematite and cristobalite together with Mn-Fe spinels if the initial ore contained Mn oxides. The admixtures of various secondary silicates were encountered as well. Low-to moderate-temperature roasting slightly affects the specific surface area and lowers volume of micropores. The hightemperature transformations lead to decrease in the specific surface area and to the destruction of porous texture of the bog iron ores. Although the general course of the processes during roasting was similar in all the samples, some of their details as well as mineralogy and properties of the products are highly dependent on the composition of the initial material.

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Thermal behavior and evolution of the mineral phases of Brazilian red mud

Cited by 37 publications

References 30 publications

Application of bauxite waste from amazon region in the heavy clay industry

Application of bauxite waste from amazon region in the heavy clay industry

Thin films produced on 5052 aluminum alloy by plasma electrolytic oxydation with Red Mud-containing Electrolytes

Mineral transformations and textural evolution during roasting of bog iron ores

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