| 摘要: |
| 采用碱性水热合成方法制备Si-MCM41,借助X射线衍射、N2吸附-脱附等表征手段系统研究晶化温度、晶 化时间和碱量对其长程有序结构的影响。实验结果表明，随着碱用量的增加,产物的长程有序结构逐渐完善,但n (TMA0H)/ra(Si02) =0.68时，必须通过晶化过程中对pH值进行调节才可得到规整性更好的MCM41。 当/i(TMA0H)/n(Si02) =2时，MCM41的X射线衍射特征峰强度变小，长程结构有序度降低。碱用量高会对比表 面积产生负面影响,适宜的碱用量为n(TMA0H)/n(Si02) =0.3。通过考察六方晶相的生长和完善以及孔壁的厚 度、比表面积等因素,确定晶化时间为5 d。温度升高导致六方骨架上的硅物种缩聚速度增大,在150 T的水热合成 环境中，MCM41的长程有序结构遭到破坏，较理想的晶化温度为丨20弋。 |
| 关键词: Si-MCM41 合成；孔结构；PH值调节；比表面积；孔壁厚度 |
| DOI： |
| 分类号: |
| 基金项目:中国石油天然气股份公司项目(YJY2005KGK-KF-021) |
|
| Synthesis method and its influence factors of Si-MCM41 |
|
ZHANG Jian-guo1,JIANG Qing-zhe1,ZHENG Cheng-guo2,SONG Zhao-zheng1,KE Ming1
|
|
(1.State Key Laboratory of Heavy Oil Processing in China University of Petroleum, Beijing \02249 f China;2. Crude Stable Plant in Tuha Oilfield Companyf Shanshan 838202，Xinjiangf China)
|
| Abstract: |
| The several influence factors including crystallization temperature, crystallization time and base dosage on hydro thermally synthesizing Si-MCM-41 mesoporous structure were discussed using X-ray diffraction (XRD) and N2-adsorption-desorption method. The results show that with the increasing of Tetramethylammoniumhydroxide (TMA0H)/Si02 molar ratio, the long-range array structure of produced samples becomes perfect gradually. However, when n( TMAOH)/?( Si02) equals 0. 68，high ordered level of Si-MCM41 can be only obtained on the premise of pH value adjustment during the course of synthesis. When n( TMAOH )/n{ Si02) equals 2, the main peak of typical XRD pattern of Si-MCM-41 becomes less in-tense ，and regular hexagonal pore packing deteriorates. At the same time , base dosage has negative influence on the specific surface area of Si-MCM-41, so the suitable ?(TMA0H)/n( Si02) is 0. 3. The satisfying time span should reach 5 days in order to obtain high quality of hexagonal mesophase by investigating pore wall thickness and the specific Surface area. Enhancement of crystallization temperature benefits the speed of the condensation of silicate species on Si-MCM41 framework. At 150 °C，pore structure comes to collapse , samples lose characteristic peaks , therefore 120 ^ can be chosen as relatively favorable crystallization temperature. |
| Key words: Si-MCM-41 synthesis pore structure pH value adjustment specific surface area pore wall thickness |
