Influence of scCO2, Ultrasound, and Quaternary Ammonium Salt on Gelation Time and Structural Characteristics of Silica. Issue 11 (8th October 2014)

• Record Type: Journal Article
• Authors: Hanu, Alina‐Mihaela; Kareth, Sabine; Puls, Angela; Ivanova, Mihaela; Mallick, Bert; Mudring, Anja‐Verena; Petermann, Marcus; Schlücker, Eberhard
• Is Part Of: Chemical engineering & technology. Volume 37:Issue 11(2014:Nov.)
• Page Start: 1873
• Page End: 1878
• Publication Date: 2014-10-08
• Subjects: Chemical engineering -- Periodicals; Chemical processes -- Periodicals; 660.05
• DOI: 10.1002/ceat.201300722
• Languages: English
• ISSNs: 0930-7516

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>In situ synthesis of silica gels via a one‐step sol‐gel process at ambient pressure or in supercritical CO₂ was investigated. The influence of compressed gas, ultrasound irradiation, and quaternary ammonium salt (choline chloride) on the gelation time was determined. The obtained samples were characterized by N₂ adsorption/desorption measurements, scanning electron microscopy in combination with energy dispersive X‐ray spectroscopy (SEM/EDX), and Fourier transform infrared‐attenuated total reflection spectroscopy (FTIR‐ATR). The retention capacity of the corresponding silica aerogels for Rhodamine B was evaluated as a model for organic water pollutants. The obtained results proved that scCO₂ has a beneficial effect, leading to a reduction of the gelation time. The obtained aerogels exhibit a higher surface area and larger pore diameter as well as a well‐defined cylindrical pore structure.</p> </abstract>