Gaggero Giulia, Subrahmanyam Raman P, Schroeter Baldur, Gurikov Pavel, Delucchi Marina
Department of Civil, Chemical and Environmental Engineering, University of Genoa, Via All'Opera Pia 15, 16145 Genoa, Italy.
Institute of Thermal Separation Processes, Hamburg University of Technology, Eißendorfer Straße 38, 21073 Hamburg, Germany.
Gels. 2022 Oct 26;8(11):691. doi: 10.3390/gels8110691.
In this work, organic aerogels from spent ground coffee and apple pomace were prepared and characterized for the first time. Apple aerogel was found to be much lighter than that from coffee (0.19 vs. 0.016 g/cm, whereas the specific surface areas are comparable (229 vs. 208 m/g). Being intrinsically hydrophilic, these aerogels were silanized, both in liquid and gas phase, to increase stability in aqueous media. The latter modification method allowed chemical grafting of the silane to the aerogel surface (evidenced by FTIR and TGA) and resulted in certain hydrophobicity, as was evidenced via contact angle measurements: both aerogels possess a contact angle of ca. 100° after the gas hydrophobization, while for the pristine aerogels it was 50°. Furthermore, it was observed that the gas-phase silanization process is more applicable to apple aerogels.
在这项工作中，首次制备并表征了由废咖啡渣和苹果渣制成的有机气凝胶。发现苹果气凝胶比咖啡气凝胶轻得多（0.19 克/立方厘米对 0.016 克/立方厘米），而比表面积相当（229 平方米/克对 208 平方米/克）。由于这些气凝胶本质上是亲水的，因此在液相和气相中都进行了硅烷化处理，以提高在水性介质中的稳定性。后一种改性方法使硅烷化学接枝到气凝胶表面（通过傅里叶变换红外光谱和热重分析证明），并产生了一定的疏水性，这通过接触角测量得到证明：两种气凝胶在气相疏水化后接触角约为 100°，而原始气凝胶的接触角为 50°。此外，观察到气相硅烷化过程更适用于苹果气凝胶。
