以秸秆、石墨为原料,采用酸碱两步法制备出纳米纤维素,石墨经Hummers法制备石墨烯悬浮液,将纳米纤维素与不同含量石墨烯悬浮液溶解于NaOH/尿素/水体系中,经溶剂置换、冷冻干燥等工艺制备出石墨烯/纳米纤维素复合气凝胶。利用傅里叶变换红外光谱仪对纳米纤维素的结构进行表征,通过扫描电子显微镜、比表面积及孔径分析仪对复合气凝胶的微观形貌和孔径进行分析,研究了复合气凝胶的油污吸附性能。结果表明:成功制备了纳米纤维素,石墨烯/纳米纤维素复合气凝胶具有完整的三维网络结构,且两相分布均匀,界面交联良好;当石墨烯质量分数为10%时,复合气凝胶的平均孔径为12.79nm,比表面积为359.3578m2/g,对油污的最大吸附量可达自身质量的12.4倍。
Straw and graphite oxide (GO)as main raw materials,nanocellulose was prepared by the acid-base two-step method of straw.GO suspension was prepared by Hummers method from graphite.Then the prepared nanocellulose and GO suspension with different content were dissolved in NaOH/urea/water system.Graphene/straw based aerogels were prepared by solvent replacement and freeze-drying.The structure of nanocellulose was characterized by Fourier transform infrared spectrometer (FT-IR).The microstructure and pore size of the aerogels were measured by scanning electron microscope (SEM) and BET.The adsorption properties of the aerogels were tested.The results showed that the straw was successfully treated to nanocellulose,graphene/straw based aerogel had a good three-dimensional network structure,and the two phases were uniformly distributed,and the interface crosslinking was good.When the content of graphene was 10wt%,the average pore size and specific surface area of the aerogels were 12.79nm and 359.3578m2/g,respectively.The maximum adsorption capacity of the aerogels was 12.4 times of their own mass.
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基金资助
天津市大学生创新创业训练计划项目(201810792050);国家自然科学基金面上项目(51772202)