全硅MCM-41中孔分子筛的合成

Synthesis of Silica Mesoporous Molecular Sieve MCM-41

在碱性条件下，采用水热晶化法，以水玻璃为硅源，表面活性剂十六烷基三甲基溴化铵为结构模板剂，成功合成出全硅MCM-41中孔分子筛。采用X射线衍射分析研究了合成条件(pH值)、凝胶配比(表面活性剂/SiO2、H2O/SiO2)和凝胶后处理条件(老化时间、晶化温度、晶化时间和焙烧温度)对MCM-41结构的影响, 结果表明全硅MCM-41的合成条件为pH 10.5～12.5，表面活性剂/SiO2 0.05～0.7，H2O/SiO2 40～200，老化时间长对合成晶形较好的全硅MCM-41有利，晶化温度70℃～100℃，晶化时间24小时，焙烧温度540℃～740℃。

Under the alkaline condition, the synthesis of mesoporous molecular sieves MCM-41 had been accomplished successfully in a hydrothermal system using sodium silicate as the source of silicon and surfactant C16H33(CH3)3NBr as structural template. The technique of X-ray diffraction was used to identify the effects of the synthesis pH condition, the composition of gel (surfactant/SiO2, H2O/SiO2) and treating conditions of gel (aging time, crystallizing temperature, crystallizing time, calcined temperature) on the crystal structure of MCM-41. The results show that the synthesis conditions for getting suitable mesoporous molecular sieves MCM-41 are pH=10.5-12.5, surfactant/SiO2=0.05-0.7, H2O/SiO2=40-200, aging time as long as possible, crystallizing temperature 70°C-100°C, crystallizing time 24 hours and calcined temperature 540°C-740°C.