SiO_2气凝胶/活性炭复合吸附材料的制备与疏水改性研究

Preparation and hydrophobic modification of SiO_2 aerogel/activated carbon composite adsorption materials

为了提高活性炭的疏水性能,采用溶胶-凝胶工艺和常压干燥法在活性炭表面上原位合成SiO_2气凝胶,并对其进行了疏水改性。扫描电镜、氮气吸脱附等温线、红外光谱分析和表面接触角测试结果表明,该工艺在活性炭孔隙内有效形成了气凝胶结构。相比于活性炭基体材料,经改性后比表面积降低5.78%,中孔结构得到增强,且有很好的疏水效果,接触角可以达到130°,对水蒸气的吸附量降低了25%。

In order to improve the hydrophobic property of activated carbon, SiO2 aerogel was in-situ synthesized on activated carbon by sol-gel process and ambient drying method. Afterwards, the SiO2 aerogel/activated carbon composites were hydrophobically modified by trimethylchlorosilane. The morphology and hydrophobicity were investigated by SEM, FTIR, nitrogen adsorption and contact angle measurement. The experimental results show that the aerogel structure was effectively formed in the pores of activated carbon by in-situ process. Compared with activated carbon, the specific surface area of modified SiO2 aerogel activated carbon decreased by 5.78%, with pore structure increasing and good hydrophobic effect improving, and its contact angle can reach 130°, which the adsorption of water vapor reduced by 25%.