氨基改性纳米纤维素气凝胶的制备及吸附性能研究

Preparation and Adsorption Properties of Ammonia Modified Nano Cellulose Aerogels

为了改善和提高纳米纤维素(CNF)气凝胶对CO_2的吸附选择性及吸附能力,采用3-(2-氨基乙氨基)丙基甲基二甲氧基硅烷作为改性剂对球形水凝胶进行接枝改性,再经冷冻干燥制备氨基改性CNF气凝胶。通过傅里叶变换红外光谱、扫描电子显微镜、比表面积孔隙测定仪等对气凝胶进行表征,并进行CO_2吸附/解吸测试。结果表明:改性CNF气凝胶对CO_2的吸附能力随着氮含量的增加而增加;在初始压力0.13 MPa,温度20℃时,CO_2吸附量最大为1.80 mmol/g,远大于未改性CNF气凝胶吸附量;经10次吸附/解吸循环,其吸附能力基本稳定,具有良好再生能力。

In order to improve and enhance the adsorption selectivity and adsorption capacity of nano cellulose（ CNF） aerogels on CO2,The spherical hydrogels prepared were graft modified with 3-（ 2-aminoethylamino） propylmethyldimethoxysilane as modifier,and then freeze-dried to prepare amino-modified CNF aerogels. The aerogels were characterized by Fourier transform infrared spectroscopy,scanning electron microscopy,specific surface area porosimeter,and conduct CO_2 adsorption/desorption test. The results showed that the adsorption capacity of modified CNF aerogels increased with the increase of nitrogen content. When the initial pressure is 0. 13 MPa and the temperature is 20 ℃,the maximum CO2 adsorption capacity is 1. 80 mmol/g,which is much larger than that of unmodified CNF aerogels. After 10 adsorption/desorption cycles,its adsorption capacity is basically stable with good regeneration capacity.