高吸附性能的介孔磁性复合碳球的制备

Preparation of Mesoporous Magnetic Carbon Spheres with High Adsorption Properties

摘要:

以正硅酸乙酯（TEOS）作为硅前驱体，在表面活性剂十六烷基三甲基溴化铵（CTAB）的辅助作用下，采用原位聚合法制备介孔磁性复合碳球，考察了醇水比（V乙醇:V水）、表面活性剂CTAB用量和水热温度（HT）等合成条件对复合碳球的形貌、粒径和表面孔结构的影响，采用TEM、SEM、BET、VSM等对碳球进行表征分析。结果表明：醇水比和表面活性剂显著影响碳球的形貌和粒径大小，水热温度可改变碳球的表面孔结构。在V乙醇:V水=3:4、CTAB=0.6g、HT=100℃的优化条件下制备的介孔磁性复合碳球的比表面积为553m2/g，较硅前驱体引入前增大2.7倍，介孔孔容占比由18%增大到83%。同时，考察该材料对红霉素的吸附性能，饱和吸附量为255mg/g；用乙酸正丁酯对吸附后材料进行再生，五次循环再生后吸附量维持在初始吸附量的85%以上。

Abstract:

Mesoporous magnetic composite carbon spheres were prepared by in-situ polymerization using tetraethyl orthosilicate (TEOS) as the silicon precursor under the assistance of surfactant cetyltrimethyl ammonium bromide (CTAB).The effects of ethanol-water ratio (Vethanol:Vwater), CTAB dosage and hydrothermal tem-perature (HT) on morphology, particle size and surface structure of carbon spheres were investigated. TEM, SEM, BET and VSM were used to characterize and analyze of carbon spheres. The results show that the ethanol-water ratio and surfactant significantly affect the morphology and particle size of the carbon spheres. In addition, the hydrothermal temperature can change the pore structure of the carbon spheres. The specific surface area of the mesoporous magnetic composite carbon spheres prepared under optimized conditions of Vethanol:Vwater=3:4, CTAB=0.6g, HT=100℃is 553m2/g, which is 2.7 times higher than that before the introduction of the silicon precursor. Moreover mesoporous pore volume ratio in-creased from 18% to 83%. At the same time, the adsorption properties of the material on erythromycin was investigated, and the saturated adsorption capacity was 255mg/g. The adsorbed material was regen-erated with n-butyl acetate, and the adsorption amount was maintain at over 85% of the initial adsorption amount after five cycles of regeneration.