Preparation of Self‐Catalyzing Sols in the 40SiO2 – 30FeO – 20FeO – 20CaO – 10Na2O Glass System by Sol‐Gel Method

• Published in: ChemistrySelect (Weinheim) Vol. 8; no. 6
• Main Authors: Rezvani, M., Oskoui, P. Rastgoo, Kianvash, A.
• Format: Journal Article
• Language: English
• Published: 10-02-2023
• Subjects: glasses; nitrous acid; precursor peaks; self-catalyzing sol; sol-gel processes
• ISSN: 2365-6549; 2365-6549
• DOI: 10.1002/slct.202204343

In this research, the self‐catalyzing sol method was used to prepare amorphous glass. In this method, as a result of the reaction between iron nitrate and ethanol, nitrous acid was synthesized. Nitrous acid reduced pH and acted as a catalyst ethanol oxidation to ethanoic acid. Different factors affect the preparation of self‐catalyzing sol and the amount of synthesized acid (aging time, temperature of sol preparation, and ratio of precursor to solvent). It was seen that the aging time had the greatest effect in reducing the pH of the sol. Ethanol oxidation was measured by gas chromatography (GC), and it was observed that approximately 95 % of ethanol was converted to ethanoic acid. The optimum glass was heat treated at different temperatures. Maghemite, hematite, and sodium calcium silicate phases were crystallized. The maximum saturation magnetization of the sample treated at 680 °C was 0.27 emu/g.
In self‐catalyzing sol method, as a result of the reaction between iron nitrate and ethanol, nitrous acid was synthesized. Nitrous acid reduced pH and acted as a catalyst ethanol oxidation to ethanoic acid. Different factors affect the preparation of self‐catalyzing sol and the amount of synthesized acid which include aging time, temperature of sol preparation, and ratio of precursor to solvent.