表面金属有机化学:SnMe_4在HY沸石超笼表面的接枝反应

Surface Organometallic Chemistry: Grafting Reaction of SnMe_4 on HY Zeolite Supercage Surface

研究了高真空条件下SnMe4在HY沸石超笼的接枝反应 ,并用元素分析 ,ICP ,GC ,XRD ,FTIR ,DTG ,DTA ,UV vis ,DRS ,N2 吸附等方法对产物的组成、结构和性质进行了详细表征 .研究结果表明 ,两者可以定量地、有选择性地进行化学反应 ,将确定数目的三甲基锡基团接枝在沸石的超笼中 .反应可以在非常低的温度下快速进行 ,表观活化能为 10 .4kJ·mol-1.经SnMe4改性后的HY沸石分子筛BET比表面积降低 ,孔体积变小 。

The grafting reaction of SnMe_4 onto the supercages of HY zeolite was studied under high vacuum condition, and the chemical composition and structure of resulting solid were characterized by in situ FT-IR, XRD, UV-Vis, DRS, DTG, DTA, N_2 adsorption, ICP, elemental analysis, and gas chromatography. The reaction could occur rapidly and quantitatively at low temperature down to 188 K (apparent active energy was 10 4 kJ·mol -1), resulting in the grafting of well-defined -Sn(CH_3)_3 fragments onto the surface of zeolite supercages. The grafted Y zeolite is quite different from the starting HY zeolite in adsorption properties, and showed obvious size-selectivity for hydrocarbons.