Characterization of diatomite from Sig region (West Algeria) for industrial application

Meradi, Hazem; Atoui, L.; Bahloul, Lynda; Labiod, Kotbia; Ismail, Fadhel

doi:10.1108/meq-04-2015-0057

Cited by 6 publications

(5 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The calcination is part of the sample pretreatment and is crucial for thermal stability. It reduces the mass of biosilica by about 40%, which is in accordance with other studies reporting a mass loss of 20% (Meradi et al, 2016) to 50% (Jiang et al, 2014) for the calcination of cultivated and chemically pretreated diatom cells. For untreated diatomite, lower losses of about 10% are reported (Fuya et al, 1995;Nowak et al, 2019).…”

Section: Thermal Analysissupporting

confidence: 92%

See 1 more Smart Citation

Detection and Localization of Eu on Biosilica by Analytical Scanning Electron Microscopy

Hieckmann

Kammerlander

Köhler

et al. 2021

Microscopy and Microanalysis

View full text Add to dashboard Cite

Algae like diatoms are widely studied as a means to remediate anthropogenically contaminated sites. In the present study, CL (cathodoluminescence) and EDX (energy-dispersive X-ray) spectroscopy in an SEM (scanning electron microscope) were optimized for the detection of Eu(III) sorbed on diatom biosilica. The required stability of biosilica under a focused electron beam was extensively investigated. Using experimentally determined data of thermal properties, the temperature increase within biosilica exposed to an electron beam was simulated by finite element calculations based on results from Monte Carlo simulations of electron scattering. Complementary thermogravimetric studies substantiated a chemical stability of biosilica in a wide temperature range, confirming its suitability for long-lasting SEM investigations. In subsequent EDX measurements, characteristic Eu lines were detected. Eu was found to preferentially accumulate and aggregate on silica fragments. CL spectra were obtained for the Eu(III) reference material, EuCl3. For Eu-loaded biosilica, even parts without detectable Eu signal in the EDX spectra show significant Eu(III) signals in the CL spectra. This highlights the sensitivity of CL in studying f-element sorption. CL data showed that Eu(III) was distributed on the entire surface. In conclusion, this work demonstrates the merit of CL and EDX methods for sorption studies on biogenic materials.

show abstract

Section: Thermal Analysissupporting

confidence: 92%

“…No significant water signals due to pore water removal or condensation of the surficial silanol groups to siloxanes (Meradi et al, 2016) can be observed in both DTA/TG and MS graphs. To a certain degree, siloxane groups could have already formed during the thermal pretreatment of the biosilica at 550°C.…”

Section: Thermal Analysismentioning

confidence: 94%

Detection and Localization of Eu on Biosilica by Analytical Scanning Electron Microscopy

Hieckmann

Kammerlander

Köhler

et al. 2021

Microscopy and Microanalysis

View full text Add to dashboard Cite

show abstract

“…Similar observations on the morphology of Algerian Sig diatomite have been reported by several authors. 3,5,21,22 In addition, there is a significant influence of washing on the acid-base behaviour of diatomaceous earth powders. In fact, washing leads to an overall and significant increase in the values of ΔG AB .…”

Section: Characterization Of the Different Chromatographic Supportsmentioning

confidence: 99%

Preparation of Chromatographic Media from Algerian Diatomite

Daoui-Bahar

Boutoumi

Bouhamidi

2022

Kemija U Industriji

View full text Add to dashboard Cite

X-ray photoelectron spectrometry combined with FTIR spectroscopy, X-ray diffraction analysis (XRD), and scanning electron microscopy (SEM) allowed highlighting the different interactions of grafts or impregnated polymers on the mineral surface of diatomite obtained by treatment of raw diatomite under reflux with a 5 M solution of hydrochloric acid for 24 h. This acid treatment led to almost total elimination of organic impurities with a total decalcification of the diatomite, leading to its deferrization and partial dealumination, and the obtaining of a support with a homogeneous siliceous surface mainly constituted of Si−OH and Si−O−Si functional groups. The surface of the diatomite washed with HCl became totally saturated with PEG-20M and SE30 with respective impregnation rates of 5 and 2 %. However, the grafting and/or impregnation of this diatomite with octadecyltrichlorosilane (C18) and docosane (C22) led to the formation of perfectly homogeneous surfaces.

show abstract

“…In order to overcome these problems and to increase the applicability temperature of diatomite as well, calcium oxide was added, in the form of chalk, with different mass ratios from 0 to 30%. This reaction between chalk and the diatomitic silica will result in the formation of wollastonite (CaO.SiO 2 ) mineral and accordingly, the chance of cristobalite formation will be decreased, resulting in increasing the applicable firing temperature (Kashcheev et al 2009a;Meradi et al 2015;Merado et al 2016;Galzerano et al 2018).…”

Section: Introductionmentioning

confidence: 99%

To blend is a good solution to improve the heat insulation applicability of diatomite ores

et al. 2018

View full text Add to dashboard Cite

Background: The idea of mixing different grades of diatomite ores with certain ratios to obtain blends with tailored minerals constitution that can help on improving their thermal insulation applicability is introduced in this study. In this respect, three diatomite samples were collected for investigation from El-Masakheet, Kasr El-Sagha, and Demia deposits, El-Fayoum, Egypt. Complete chemical and phase analyses of these samples were carried out. The analyses showed that El-Masakheet sample was of low-grade diatomite with excess calcite content. In addition, Kasr El-Sagha and Demia samples were of high-grade diatomite with minor calcite contents. By firing the dried Kasr El Sagha and Demia yellow samples specimens at different temperatures for 1 h, they showed complete destruction at 900°C. Different amounts of El-Masakheet sample was blended with Kasr El-Sagha and Demia yellow samples. The specimens were subjected to firing at different temperatures for 1 h. The physical properties of the fired mixed specimens were followed up. Results: Results showed that by blending El-Masakheet sample with 50% mass ratio with Kasr El-Sagha or Demia yellow samples, a pronounced increase in the thermal applicability of the fired blends from 900 to 1100°C was achieved. In addition, a notable increase in their open porosity was recorded. This improvement was attributed to the change in the minerals constitution ratios in the blends due to the increase in their calcite contents after El Masakheet addition, especially the Ca/Si and Ca/(Al + Si) atom ratios. This change served in forming high melting points minerals like αwollastonite and akermanite on firing the blends specimens instead of low melting point minerals like cristobalite and alkali aluminosilicate which were formed on firing the high-grade ores alone. Consequently, an increasing in the porosity and the thermal applicability of the new specimens from 900 to 1100°C was achieved. Conclusions: The idea of mixing different grades of diatomite ores with certain ratios to obtain blends with tailored minerals constitution can help on improving their thermal insulation applicability and their open porosity. Besides, this concept gave a good solution to get use of the unexploited low-grade diatomite ores, especially of high calcite content.

show abstract

Characterization of diatomite from Sig region (West Algeria) for industrial application

Cited by 6 publications

References 18 publications

Detection and Localization of Eu on Biosilica by Analytical Scanning Electron Microscopy

Detection and Localization of Eu on Biosilica by Analytical Scanning Electron Microscopy

Preparation of Chromatographic Media from Algerian Diatomite

To blend is a good solution to improve the heat insulation applicability of diatomite ores

Contact Info

Product

Resources

About