二氧化硅气凝胶微球的制备与表征

Preparation and Characterization of Silica Aerogel Microspheres.

作者信息

Chen Qifeng, Wang Hui, Sun Luyi

机构信息

College of Materials Science & Engineering, South China University of Technology, Guangzhou 510640, China.

Department of Chemical & Biomolecular Engineering and Polymer Program, Institute of Materials Science, University of Connecticut, Storrs, CT 06269, USA.

出版信息

Materials (Basel). 2017 Apr 20;10(4):435. doi: 10.3390/ma10040435.

DOI:10.3390/ma10040435

PMID:28772795

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC5506966/

Abstract

Silica aerogel microspheres based on alkali silica sol were synthesized using the emulsion method. The experimental results revealed that the silica aerogel microspheres (4-20 µm in diameter) were mesoporous solids with an average pore diameter ranging from 6 to 35 nm. The tapping densities and specific surface areas of the aerogel microspheres are in the range of 0.112-0.287 g/cm³ and 207.5-660.6 m²/g, respectively. The diameter of the silica aerogel microspheres could be tailored by varying the processing conditions including agitation rate, water/oil ratio, mass ratio of Span 80: Tween 80, and emulsifier concentration. The effects of these parameters on the morphology and textural properties of the synthesized silica aerogel microspheres were systematically investigated. Such silica aerogel microspheres can be used to prepare large-scale silica aerogels at an ambient pressure for applications in separation and high efficiency catalysis, which requires features of high porosity and easy fill and recovery.

摘要

采用乳液法合成了基于碱性硅溶胶的二氧化硅气凝胶微球。实验结果表明，二氧化硅气凝胶微球（直径4 - 20 µm）为介孔固体，平均孔径范围为6至35 nm。气凝胶微球的振实密度和比表面积分别在0.112 - 0.287 g/cm³和207.5 - 660.6 m²/g范围内。通过改变包括搅拌速率、水/油比、Span 80与Tween 80的质量比以及乳化剂浓度等加工条件，可以调整二氧化硅气凝胶微球的直径。系统研究了这些参数对合成的二氧化硅气凝胶微球的形态和结构性质的影响。这种二氧化硅气凝胶微球可用于在常压下制备大规模二氧化硅气凝胶，用于分离和高效催化应用，这些应用需要高孔隙率以及易于填充和回收的特性。