过氧化氢溶液中痕量离子吸附分离用氨基功能化SBA-15的制备及性能

通过后接枝法制备了氨基功能化SBA-15介孔氧化硅（S-N），用于吸附过氧化氢溶液中的金属和阴离子及有机杂质制高纯过氧化氢。研究了接枝量对吸附剂结构和性能的影响并发现S-N中的氮含量随接枝剂用量增加而增加，最高为1.83%。S-N保留了高度有序的六方孔道结构，但比表面积和孔体积均随接枝量增加而下降。在过氧化氢溶液中，各吸附剂表面均带正电荷。氨基功能化可显著提高SBA-15对Al³⁺和Fe³⁺离子的吸附能力，2者净化率分别达到82.22%和78.78%。对Ca²⁺和K⁺及Na⁺、磷酸根和有机杂质的吸附能力也有明显提高。阴、阳离子的吸附等温线和吸附动力学显示，2者均为化学吸附。S-N主要通过络合作用吸附金属离子、通过静电作用吸附磷酸根，对有机杂质则以物理吸附为主。

Preparation and performance of amino-functionalized SBA-15 for adsorption of ions in hydrogen peroxide solution

Amino-functionalized mesoporous silica SBA-15 was prepared with 3-aminopropyltriethoxysilane (APTES) via post-synthesis grafting method and used as absorbents for removal of metal ions, anions and organic impurities from a hydrogen peroxide solution to produce ultra-pure hydrogen peroxide. The results showed that the N content in amino-functionalized SBA-15 increases with increasing the addition amount of APTES, with a maximum of 1.83%. Two-dimensional hexagonal ordered structure of SBA-15 is well preserved after grafting with APTES. However, the specific surface area and pore volume of SBA-15 decrease slightly with increasing the grafting amount. The surface of SBA-15 in the hydrogen peroxide solution has positive charge. The functionalization of SBA-15 by grafting of amino groups induces an extremely significant improvement in the adsorption capacity for Al³⁺ and Fe³⁺ with purification rate of 82.22% and 78.78%, and the moderate improvement for Ca²⁺, K⁺, Na⁺, PO₄^3- and organic impurities in the hydrogen peroxide solution. Kinetic studies and adsorption isotherm data indicated that adsorption of metal ions and PO₄^3- was chemical adsorption. It has been speculated that metal ions are removed from the hydrogen peroxide solution by complexation with the surface of SBA-15, and PO₄^3- and organic impurities by electrostatic and physical adsorption, respectively.