Development of hydrophobic and monolithic MTES /Water glass Based Silica Aerogels for an efficient organic pollutant adsorption

Abstract

In this investigation, silica aerogels were synthesized employing a co-precursor approach involving water glass (WG) and methyltriethoxysilane (MTES) through the sol-gel method, followed by ambient pressure drying as an efficient adsorbent for organic pollutant. The microstructure, hydrophobicity, and adsorption property were studied as a function of the MTES/WG molar ratio. The aerogel achieved commendable characteristics, including a low density of 0.088 g/cm³, a high contact angle of 160°, and an elevated surface area of 636 m²/g, when maintaining a molar ratio of MTES to WG at 3.5. The adsorption intensity of the aerogel towards toluene, n-hexane, crude oil, gasoline, and ethanol was 9.58, 8.4, 10.2, 12, and 14 gr/gr, respectively. Finally, the reproducible absorption feature showed that the aerogel kept its original shape, and adsorption property until the fourth cycle, which can be a promising candidate for crude oil clean-up application.