چكيده به لاتين
Monolithic silica aerogels were successfully synthesized from silicomanganese slag by the sol-gel method under ambient pressure drying. The silica source was extracted from the silicomanganese slag by a facile hydrometallurgy-based process as an economical method that replaces expensive and costly precursors with a cheap secondary resource. The extracted silica was converted to silica aerogel through gelation, three-step solvent extraction, aging and ambient pressure drying. The solvent extraction steps were carried out using different volume ratios of tert-butano and /EtOH. No surface modifier was used. The crystalline structure, chemical composition, chemical bonding, microstructure, thermal stability, and porosity were investigated by X-ray diffractometry, X-ray fluorescence, Fourier transform infrared spectroscopy, field emission electron microscopy and transmission electron microscopy, thermogravimetric and differential thermal analysis (TGA-DTA), and nitrogen sorptometry techniques, respectively. The characterization results revealed that the obtained silica aerogel had an amorphous structure having a very low density (~ 0.08 g/cm3), high specific surface area (~ 481 m2/g), large pore volume (~ 0.97 cm3/g), and average pore diameter (~ 7.5 nm). This study proposes a promising and novel method to prepare monolithic silica aerogel from a cheap silica resource under ambient pressure drying without surface modification.
