六方平板状氨基-甲基双官能化SBA-15的合成及对胆红素的吸附

Synthesis of Amine/methyl Bifunctionalized SBA-15 with Hexagonal Platelet Morphology and Its Application in Bilirubin Adsorption

以氨丙基甲基二乙氧基硅烷和正硅酸乙酯为硅源,无机盐KCl为助剂,采用一步法合成了氨基-甲基双官能化SBA-15(AMS).通过X射线衍射、红外光谱、N2吸附-脱附、核磁共振谱、扫描电镜及高分辨透射电子显微镜等手段对样品进行了表征,并对其进行了胆红素吸附研究.结果表明,无机盐不仅提高了AMS材料的介孔有序度,而且控制样品形貌从六方平板状向纤维状转变.相比于以微孔为主的活性炭,在胆红素吸附实验中,介孔材料纯SBA-15及AMS都表现出了较快的吸附速率和较大的吸附容量.六方平板状AMS比纤维状AMS和纯SBA-15具有更快的吸附速率和更大的吸附容量,这可能是六方平板状形貌易于胆红素的扩散以及双官能基团(甲基和氨基)增加了对胆红素吸附作用力的结果.

Amine/methyl bifunctionalized SBA-15 materials（AMS） were directly synthesized by co-condensation of 3-aminopropylmethyldiethoxysilane and tetraethoxysilane using an amphiphilic block copolymer as template under acidic-catalyzed and inorganic-salt-assisted conditions.X-ray diffraction,N2 sorption analysis,transmission electron microscopy,Fourier transform infrared spectra and solid-state nuclear magnetic resonance were used to identify the well-ordered mesostructure and the grafting of amine and methyl groups on the surface of the synthesized materials.The addition of inorganic salt KCl was proven to play an important role in the formation of the highly ordered mesostructure.The scanning electron microscopy images showed that the morphologies of AMS samples shifted from hexagonal platelet to fiberlike morphology with increasing KCl concentration from 1.0 mol/L to 2.0 mol/L.The AMS sample with platelet morphology exhibited faster bilirubin adsorption rate and higher bilirubin adsorption capacity than AMS and pure SBA-15 samples with fiberlike morphology.This could be attributed to the fast molecular transport based on the short mesopore channels and the strong interaction between organic groups（amine and methyl） of AMS and bilirubin molecules.Futher studies using packed-bed columns filled with AMS samples in extracorporeal recirculation units are under investigation.