Synthesis of reactive silica from kaolinitic clay: Effect of process parameters
| Autor: | Chantale Njiomou Djangang, Charles Fon Abi, Philippe Blanchart, Danie Laure Mbella Moukouri, Gustave Tchanang |
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| Rok vydání: | 2021 |
| Předmět: |
Potassium hydroxide
Aqueous solution Sodium chemistry.chemical_element 020101 civil engineering Geology 02 engineering and technology 021001 nanoscience & nanotechnology 0201 civil engineering chemistry.chemical_compound Hydrolysis Adsorption chemistry Geochemistry and Petrology Yield (chemistry) Specific surface area Fourier transform infrared spectroscopy 0210 nano-technology Nuclear chemistry |
| Zdroj: | Applied Clay Science. 207:106087 |
| ISSN: | 0169-1317 |
| DOI: | 10.1016/j.clay.2021.106087 |
| Popis: | Reactive silica was synthesised using precursors from heated kaolinitic clay at 600, 700 and 800 °C. Each precursor was dissolved in an aqueous acidic medium; the residue was treated with either sodium or potassium hydroxide solution. The solution was finally hydrolysed and polymerised using either HCl, H2SO4 or HNO3 in the presence of ethanol as a cosolvent. Products were characterised using XRD, FTIR, SEM and TEM. Results indicated amorphous nanosilica as the main phase with particle sizes of 30 ± 7 to 21 ± 3 nm for NaOH and 28 ± 7 to 16 ± 3 nm for KOH. The best process yield, 84.2%, given by the combination of 700 °C/KOH/H2SO4, and the highest specific surface area of 81.9 g .m−2, was obtained under the conditions of 700 °C/NaOH/HCl. The adsorption test of methylene blue displayed the high capacity of these products to remove organic matter, a 99.9% abatement rate, indicating their high effectiveness in depollution. |
| Databáze: | OpenAIRE |
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