高邻位酚醛基纳米活性碳纤维制备及其吸附性能

为提高酚醛基纳米活性碳纤维的吸附性能,首先采用乙酸锌、硫酸双催化合成高邻位酚醛树脂,然后配制酚醛/聚乙烯醇缩丁醛(PVB)混合溶液,采用静电纺丝、固化、炭化和活化工艺制备得到柔性高邻位酚醛基纳米活性碳纤维,借助傅里叶变换红外光谱仪、扫描电子显微镜、热重分析仪、比表面积及孔径分析仪对其结构和性能进行测试与分析。结果表明:静电纺丝制备的酚醛初生纤维在溶液固化后,酚环对位取代增加,纤维内发生了分子间交联,但PVB有一定的醇解,使酚醛纤维在炭化过程中低温稳定性下降,而高温残碳率升高,炭化后制备得到多孔碳纤维;活化后得到的高邻位酚醛基纳米活性碳纤维比表面积为1 409 m²/g,其对亚甲基蓝及碘的吸附量分别达到837和2 641 mg/g。

Preparation and adsorption performance of high-ortho phenolic resin based activated carbon nanofibers

In order to improve the adsorption performance of phenolic resin based activated carbon fibers, the high-ortho phenolic resin was catalyzed by zinc acetate and sulphuric acid, and then mixed with polyvinyl butyral(PVB)as raw material, the flexible high-ortho phenolic resin based activated carbon nanofibers were prepared by a sequence of processes, including electrospinning, consolidation, carbonization and activation, and then the structure and performance were tested and analyzed by Fourier infrared spectrum, scanning electron microscopy, thermogravimetric analysis and specific surface area and pore size distribution analyzer. The results show that the crosslinking structures of the phenolic fibers are formed with the increase of the char yield, and the thermal stability at low temperature decreases with the alcoholysis of PVB. The adsorbing evaluation demonstrates that the high specific surface area of the high-ortho phenolic resin based activated carbon nanofiber reaches 1 409 m²/g, and its adsorption capacity for methylene blue and iodine appears as high as 837 and 2 641 mg/g, respectively.