Please use this identifier to cite or link to this item:
https://hdl.handle.net/11147/12847
Title: | The effect of the temperature of heat treatment process and the concentration and duration of acid leaching on the size and crystallinity of nano-silica powders formed by the dissociation of natural diatom frustule | Authors: | Ülker, Sevkan Güden, Mustafa |
Keywords: | Acid leaching Ball milling Diatom frustules Heat treatment Nanopowder |
Issue Date: | Aug-2022 | Publisher: | American Scientific Publishers | Abstract: | The present study focused on the processing of nano-silica powders in varying sizes and crystallinities through IP: 846247.10 On: Wed, 14 Dec 2022 07:29:25 heat treatment (900-1200 degrees C), hydrofluoric acid leaching (1-7 N), and ball milling (1 h, 500 rpm) of natural Copyright American Scentfic P blishers diatom frustules. The starting natural frustules were determined to be composed of amorphous silica (88%) Delivered by Ingenta and quartz. The partially ordered crystalline low-quartz and or precursor to low-cristobalite started to form at-900 degrees C. As the heat treatment temperature increased, the crystallinity of the frustules increased from 9.3% at 25 degrees C to 46% at 1200 degrees C. Applying a ball milling reduced the mean particle sizes of the as-received and heat-treated frustules from 15.6-13.7 mu m to 7.2-6.7 mu m, respectively. Acid leaching of the as-received and heat-treated frustules resulted in a further increase in the crystallinity. Furthermore, a ball milling applied after an acid leaching was very effective in reducing the particle size of the as-received and heat-treated frustules. The mean particle size of the acid-leached frustules decreased to 774-547 nm with a crystallinity varying between 12 and 48% after ball milling. A partially dissolved amorphous phase was observed in between crystalline silica grains after acid leaching, which resulted in a rapid fracture/separation of the frustules in ball milling. | URI: | https://doi.org/10.1166/mex.2022.2251 https://hdl.handle.net/11147/12847 |
Appears in Collections: | Materials Science and Engineering / Malzeme Bilimi ve Mühendisliği Mechanical Engineering / Makina Mühendisliği WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection |
Show full item record
CORE Recommender
Items in GCRIS Repository are protected by copyright, with all rights reserved, unless otherwise indicated.