Fundamental studies of Rhodococcus opacus as a biocollector of calcite and magnesite

Botero, Ana Elisa Casas; Torem, Maurício Leonardo; Mesquita, Luciana

doi:10.1016/j.mineng.2007.03.017

Cited by 78 publications

(46 citation statements)

References 24 publications

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“…The findings of FTIR spectra of corundum are in agreement with [16] and the results obtained by [15] for interaction of hematite before and after with R. erythropolis have shown that after interaction, new surface species were found and it also proved that adsorption occurs mainly chemical adsorption which makes hematite surface hydrophobic and enhance the floatability. Similar functional groups in quartz have been observed by [17] wherein they have shown that in presence of R. opacus calcite showed the characteristic bands of carbonates. The FTIR spectra of cell free extract interacted with minerals were observed by [16] and the shift in peaks was observed due to the presence of polysaccharides on hematite and corundum.…”

Section: Discussionsupporting

confidence: 81%

Biobenefication of Oxide Minerals from <i>Bacillus subtilis</i> Using FTIR and MALDI-TOF Techniques

Sarvamangala¹,

Raghavendra²,

Girisha³

2017

JEP

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Biobeneficiation processes involving the separation of valuable minerals from ores and materials using conventional flotation and flocculation methods have been shown to be promising in recent years. There is an enormous potential to utilize microorganisms as flocculating agents, flotation collectors and/or depressants. The study involves Biobeneficiation of oxide minerals using Bacillus subtilis. Characterization of minerals (hematite, corundum, calcite and quartz) was carried out through XRD, EDAX and FTIR techniques. FTIR of minerals before and after interaction with cells, cell free extract and extracellular proteins was carried out and it has been found that there is a shift or change in the peaks of functional groups. In presence of protein adsorption, amide peaks were found and in case of polysaccharide adsorption, carboxyl peaks were found which justify the flotation and flocculation results. MALDI-TOF was carried out to confirm the molecular weights of the extracted proteins and it was found that molecular weight of proteins on interaction with minerals was higher than that of uninteracted minerals.

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Section: Discussionsupporting

confidence: 81%

Biobenefication of Oxide Minerals from <i>Bacillus subtilis</i> Using FTIR and MALDI-TOF Techniques

Sarvamangala¹,

Raghavendra²,

Girisha³

2017

JEP

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“…1(a) shows the zeta potential of the microorganism at different pH values. Initially, we observed an isoelectric point (IEP) of approximately 2.8, as found in previous works (Botero et al, 2007(Botero et al, , 2008Mesquita et al, 2003;Merma et al, 2013). According to several authors (Rao and Subramanian, 2007;Natarajan, 2006;Vilinska and Rao., 2008;Faharat et al, 2008;Van Der Wal et al, 1997), this acidic value is related to the higher presence of anionic functional groups compared with cationic groups.…”

Section: Zeta Potential Studiessupporting

confidence: 82%

“…Thus, considering that phosphate ores are associated with several gangue minerals, especially quartz, carbonates and silicates, then a detailed bioflotation study of each component is necessary to establish the bioflotation of phosphate ores. One bacteria, quite recently used in mineral bioflotation, is Rhodococcus opacus (Botero et al, 2007;Mesquita et al, 2003;Botero et al, 2008;Merma et al, 2013). It is a Gram positive bacterium with different types of components on their cell-wall, which are primarily polysaccharides, carboxylic acids, lipid groups and mycolic acids, that result in amphoteric behavior (hydrophobic and/or hydrophilic properties) of the bacteria (Mesquita et al, 2003;Natarajan, 2006;Vilinska and Rao., 2008).…”

Section: Introductionmentioning

confidence: 99%

Cellular Adaptation: Culture conditions of R. opacus and bioflotation of apatite and quartz

2017

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It is well known that the culture conditions of microorganisms may affect their surface properties, zeta potential and hydrophobicity via the modification of the cell wall functional groups or metabolic products. The R. opacus bacteria strain was separately adapted to the presence of apatite and quartz, after which a cellular adaptation procedure was developed by repeated sub-culturing with a successive increase in the mineral content. Zeta potential, surface tension, FTIR and microflotation studies were used to evaluate the behavior of the cells that were developed under defined culture conditions. The cellular adaptation induced a modification of the bacterial surface charge. The FTIR results showed a modification of its functional groups. The surface tension results suggested that longer growing time promoted a higher production of metabolites. The use of mineral-adapted cells promoted an improvement in the flotability of both minerals, but it was more significant for apatite flotation. Additionally, the mineral flotability remained unchanged when the cells developed under a longer culture time. Nevertheless, there was a reduction in the surface tension.

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“…Especially, flotation is one of the most effective methods to increase the recovery of fine-grained and low-grade magnesite. In recent years, mineral processors dealing with magnesite have faced a difficult problem in that the flotation results of magnesite are not ideal in the presence of carbonate minerals, such as calcite and dolomite [3,4]. Dolomite (CaMg(CO 3 ) 2 ) which is one of the most common and typical carbonate gangues, often coexists with rhodochrosite, smithsonite, magnesite, and pyrite [5][6][7][8][9][10].…”

Section: Introductionmentioning

confidence: 99%

Elimination of the Adverse Effect of Calcium Ion on the Flotation Separation of Magnesite from Dolomite

et al. 2017

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Abstract:The separation of magnesite from dolomite was studied by flotation tests, X-ray photoelectron spectroscopy (XPS), and zeta potential measurements in the presence of calcium ion (Ca 2+ ) dissolved from dolomite. Sodium oleate (NaOL) was used as collector, and sodium carbonate (Na 2 CO 3 ) and sodium hexametaphosphate (SH) were used as regulators. The results showed that SH had a good selective inhibition ability in pure mineral flotations of magnesite and dolomite. While in the presence of Ca 2+ dissolved from dolomite, magnesite and dolomite were both inhibited by SH. The separation of magnesite from dolomite cannot be realized because Ca 2+ can adsorb on the surface of magnesite in the form of CaCO 3 and change the surface properties of magnesite. Thus, the magnesite flotation was depressed. When the sequence of reagent addition was changed to add SH prior to Na 2 CO 3 , a complex was made by Ca 2+ reacting with SH, which avoided the adsorption of Ca 2+ on the magnesite surface and prevented the changing of the magnesite's surface properties. Then, after adjusting the solution pH with Na 2 CO 3 , the flotation separation of magnesite from dolomite could be achieved.

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Fundamental studies of Rhodococcus opacus as a biocollector of calcite and magnesite

Cited by 78 publications

References 24 publications

Biobenefication of Oxide Minerals from <i>Bacillus subtilis</i> Using FTIR and MALDI-TOF Techniques

Biobenefication of Oxide Minerals from <i>Bacillus subtilis</i> Using FTIR and MALDI-TOF Techniques

Cellular Adaptation: Culture conditions of R. opacus and bioflotation of apatite and quartz

Elimination of the Adverse Effect of Calcium Ion on the Flotation Separation of Magnesite from Dolomite

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Fundamental studies of Rhodococcus opacus as a biocollector of calcite and magnesite

Cited by 78 publications

References 24 publications

Biobenefication of Oxide Minerals from &lt;i&gt;Bacillus subtilis&lt;/i&gt; Using FTIR and MALDI-TOF Techniques

Biobenefication of Oxide Minerals from &lt;i&gt;Bacillus subtilis&lt;/i&gt; Using FTIR and MALDI-TOF Techniques

Cellular Adaptation: Culture conditions of R. opacus and bioflotation of apatite and quartz

Elimination of the Adverse Effect of Calcium Ion on the Flotation Separation of Magnesite from Dolomite

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Product

Resources

About

Biobenefication of Oxide Minerals from <i>Bacillus subtilis</i> Using FTIR and MALDI-TOF Techniques

Biobenefication of Oxide Minerals from <i>Bacillus subtilis</i> Using FTIR and MALDI-TOF Techniques