本文比较了不同碳纳米管(CNTs)对异甘草素和甘草素的吸附、解吸附性能。通过N2吸附试验、扫描电镜和红外光谱对CNTs的孔径结构、比表面积、表面形态及载带官能团进行表征,经过动态吸附和等温平衡吸附、解吸附试验,结果表明:氧化多壁碳纳米管(o—MWCNTs)对两种化合物的吸附能力大于原始多壁碳纳米管(r-MWCNTs),尤其对异甘草素的吸附能力。吸附过程符合Freundlich模型,并且吸附能力随着温度的升高而逐渐降低。CNTs等温平衡吸附、解吸附试验结果显示,o-MWCNTs对异甘草素和甘草素的吸附能力大于r—MWCNTs,并且解吸附效率较好,对异甘草素和甘草素的解吸附率分别为48.57%和32.86%,而r-MWCNTs只有24.56%和17.46%。
The adsorption and desorption of isoliquiritigenin and liquiritigenin to different types of carbon nanotubes (CNTs) were comparatively studied in this study. The pore structure, specific surface area, surface morphologies and functional groups of the CNTs were tested by N2 adsorption, scanning electron microscope (SEM) and infrared spectra (IR). The investigation of dynamic adsorption, isothermal equilibrium adsorption and desorption of isoliquiritigenin and liquiritigenin to CNTs demonstrated that the adsorption amount on oxidized multi-walled carbon nanotubes (o-MWCNTs) was greater than that on raw multi-walled carbon nanotubes (r-MWCNTs), especially the adsorption of isoliquiritigenin to o-MWCNTs. The data of equilibrium adsorption were better represented by the Freundlich isotherm model. In addition, the adsorbed amount per unit CNTs was decreased when the temperature got higher. From the results of isothermal equilibrium adsorption and desorption to CNTs, it could be inferred that o-MWCNTs had higher adsorption to isoliquiritigenin and liquiritigenin than r-MWCNTs. Additionally, o-MWCNTs had a better desorption efficiency to isoliquiritigenin and liquiritigenin (about 48.57% and 32.86%) than r-MWCNTs (about 24.56% and 17.46%).