methods to remove iron from kaolin

The purpose of the present study was to compare kaolin products obtained by currently used chemical leaching methods with a bioleaching treatment using Aspergillus niger in order to remove Fe from kaolin (from Canakkale, Turkey). The effects of pulp density, temperature, and oxalic acid concentration on the chemical leaching …

The effect of grinding causes the partial surface amorphization of kaolin particles and a decrease in the dehydroxylation temperature. The assistance of grinding leads to a higher iron removal when compared with the conventional bleaching method using sodium hydrosulfite.

2. Flotation Process Method. The flotation process can effectively remove iron, titanium and carbon impurities in kaolin, and realize the recycling and reuse of low-grade kaolin resources such as …

Chemical beneficiation methods involve the removal of mineral impurities from kaolin clay by organic and inorganic acids such as oxalic acid [9][10][11][12][13][14][15], citric acid 16, 17 ...

Toro et al. (1992) described a microbial method to remove iron impurities from kaolin ore using different bacteria including Agrobacter sp., Bacillus sp., …

Methods Of Removal Iron Impurities from Kaolin. In order to minimize the iron content in kaolin and increase its whiteness. Physical beneficiation methods are usually used to enrich kaolin raw materials or …

3.4 XRF analysis of Kaolin Treated Kaolin samples at the optimum leaching points from the selected acid concentrations in this study (i.e. 0.4 M oxalic and 0.5 M citric acids at 2 hour treatment period) were analysed along with an untreated filter cake sample by using XRF method to identify the Fe removal efficiency of the chemical leaching ...

Conclusions Two series of bacterial iron-reduction experiments have shown that all tested Shewanella sp. bacterial strains were able to leach iron impurities from industrial kaolins and that among the tested strains, S. putrefaciens CIP8040 is the most efficient in terms of both extent of Fe removal and improvement in the colour properties of ...

Iron oxide in kaolin can be removed by physical separation, e.g. flotation or magnetic separation, or by chemical leaching processes using chemicals such as Na 2 …

The results of the kaolin powder XRF showed 52% iron removal from kaolin by A. niger fungal isolated from pistachio skin after 14 days ... biological methods have been used to remove iron impurities

In more recent studies, Hajihoseini and Fakharpour (2019) showed that 47.7% of iron was reduced from kaolin with 75.41% of whiteness index that was achieved after leached with Aspergillus niger ...

Abstract. This study reports a leaching process along with a novel physical pretreatment technique to remove iron impurities from kaolin using oxalic acid. A detailed …

In this method, by discarding up to 20% of the raw material, >54% of the total iron content of the raw kaolin was removed, and the iron content was reduced from 9.75% in the initial sample to <6. ...

The reasons for the inefficacy of iron removal from Zhuravlinyi Log kaolin by dry grading into fractions method are analyzed. A biochemical kaolin-enrichment technology is proposed.

The decrease in the iron content in the TD bleached samples can be ascribed to the leaching of the Fe 3 + ions from the kaolin (Eqs. (1), (2), (3)). The removal efficiency of iron is highest in Al 3 +-assisted bleaching processes, with 43.3% (sample D 1) and 30.7% (sample D 2) of removal in Beihai and Xingzi kaolin, respectively.

In this method, by discarding up to 20% of the raw material, >54% of the total iron content of the raw kaolin was removed, and the iron content was reduced from 9.75% in the initial sample to <6. ...

Kaolin waste dumps contain a huge volume of material that cannot be commercialized due to the presence of variable amounts of iron minerals, which impart a …

The greatest degree of removal of Fe from the kaolin sample (at 15% w/v pulp density, temperature of 80 degrees C, oxalic acid concentration of 0.2 M, and a particle size of <63 mu m) was found to ...

A kinetic model was developed to assess the influence of batch cultivation of Aspergillus niger on the bioleaching of iron from kaolin. A simple model was proposed using the logistic equation for ...

The influences of temperature and thiourea dosage on the iron removal were studied for temperatures of 20 and 90 °C in solutions containing thiourea, in the absence of ultrasound. Fig. 1 shows the result of kaolin bleaching at 20 °C with the dosage range of 0.3–1.2% of thiourea dosage. It can be observed that both the dose of thiourea and …

Removing Fe3+ impurities from industrial kaolin clay is typically achieved through physical techniques (magnetic separation, selective flocculation) and chemical …

Accordingly, a pre-agitating technique followed by high-pressure washing of the sample on a 600 μm sieve were applied. In this method, by discarding up to 20% of the raw material, >54% of the total iron content of the raw kaolin was removed, and the iron content was reduced from 9.75% in the initial sample to <6.00% in the passing fraction.

iron(III) forms present in kaolin as final electron accep-tors, reducing them to iron(II) (Kostka et al., 1999;Luu &Ramsay,2003). The current study investigated chemical leaching of iron from kaolin using citric and oxalic acids, and the microbial removal of Fe(III) present in kaolin, using pure cultures of a bacterial strain. The experimental

Iron oxide existence in kaolin is biologically induced, so it is better to apply a biological process for removing it from clays by exploiting microorganisms (Poorni and Natarajan, 2013).

Kaolin waste dumps contain a huge volume of material that cannot be commercialized due to the presence of variable amounts of iron minerals, which impart a yellowish color to the kaolin. Elimination of iron from kaolin using either a chemical or a biological method was the aim of this study. The chemical leaching of iron from kaolin …

In this method, by discarding up to 20% of the raw material, >54% of the total iron content of the raw kaolin was removed, and the iron content was reduced from 9.75% in the initial sample to <6. ...

The graphical representation of global stability for a system, or Pourbaix diagram, was constructed to perform a thermodynamic study of iron removal from kaolin using oxalic acid as an oxidant. To ...

In this method, by discarding up to 20% of the raw material, >54% of the total iron content of the raw kaolin was removed, and the iron content was reduced from 9.75% in the initial sample to <6. ...

At present, the chemical iron removal methods commonly used in kaolin include oxidation method, restoration method and Chineseization-restoration combined method, among which the restoration method is the most widely used. Which method is used in detail depends on the type of iron ore contained in kaolin. (1) Oxidative iron …

2. Double-liquid layer flotation method. This method adopts a no carrier flotation method to remove titanium impurities and other minerals, which can adapt to finer kaolin (less than 2um particles more than 80%) float purification. The above are the four common iron removal methods in kaolin production process.

The purpose of the present study was to compare kaolin products obtained by currently used chemical leaching methods with a bioleaching treatment using Aspergillus niger in order to remove Fe from ...