中空介孔二氧化硅锚固聚偕胺肟吸附Cr(Ⅵ)

Polyamidoximation of Hollow Mesoporous Silica and Its Application in Adsorption of Cr(Ⅵ)

以硝酸铈铵为引发剂,在自制的中空介孔二氧化硅(HMS)的空腔和通道内引发丙烯腈自由基聚合,并将其氰基偕胺肟化,用于制备具有吸附Cr(Ⅵ)的廉价有机无机复合吸附材料——中空介孔二氧化硅锚固聚偕胺肟.通过傅里叶变换红外光谱(FTIR)、扫描电子显微镜(SEM)及N_2吸附-脱附比表面分析对中空介孔二氧化硅锚固聚偕胺肟进行表征.结果表明,制备的中空微球直径约为400 nm,其壁上孔径约为11.0 nm,比表面积约为431 m^2/g,锚固聚偕胺肟后中空微球壁上孔道直径约为4.6 nm,比表面积降低为347 m^2/g.HMS锚固的聚偕胺肟对重铬酸钾溶液中铬的吸附量高达0.46 mmol/g,吸附过程中伴随化学反应,符合伪二级动力学模型,可用作废水处理中重金属离子的高效廉价吸附材料.

Polyamidoximation of hollow cyano groups in polyacrylonitrile grafted mesoporous silica （ HMS/PAO ） from hollow mesoporous silica （ was prepared by tranforming the HMS ） through polymerization of acrylonitrile initiated by ceric ammonium nitrate. The hollow mesoporous silica was prepared by a facile one-pot sol-gel method. The microstructure and characteristic of the HMS and HMS/PAO were examined by Fourier transform Infrared spectra （FFIR）, X-ray diffraction, scanning electron microscope （SEM）, N2 adsorption desorption isotherm. The results showed that the diameter of the HMS was about 400 nm, and the size of the mesoporous was ca. 11.0 nm. The size of the mesoporous was ca. 4.6 nm and more uniform and smaller. As potassium dichromate solution（ K2Cr207 ） was used as a target solution for detecting adsorption ca- pacity of the prepared HMS/PAO, the adsorption chromium kinetics was consistent with the pseudo-second- order kinetics model by analyzing the adsorption amount as a function of the sorbent dispersed duration in solution at pH = 2. 0. The adsorption capacity of HMS/PAO for chromium was as much as 0. 46 mmol/g. Therefore, it is an adsorbent with high efficiency.