Chemical Reaction in the Confined Space of Mesoporous Molecular Sieves

• Main Authors: Chia-Hung Lee, 李佳洪
• Other Authors: Chung-Yuan Mou
• Format: Others
• Language: zh-TW
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/y5447v

碩士 === 國立臺灣大學 === 化學研究所 === 89 === The chemical reaction in confined space is very interesting because the restrictions on space will give rise to lots of differentiations and selections. We can manipulate the product of the chemical reaction through the change of experimental environment. Hereby, we make use of the restrictions on porous MCM-41 to make a study of the chemical reaction of C60 and free radicals in the confined space. C60 has multiple π electrons so it can be taken as a very nice free radicals scavenger for the addition reaction with many free radicals. We can fix C60 in the channels of MCM-41, which has high surface by special ways. Besides, we can use different ways to generate free radicals respectively outside and inside the channels. Therefore, we can study the scavenging efficiency of C60 towards free radicals inside the channels. Among them, we find that free radicals generating from the inner channels can be eliminated quickly by the adjacent C60. However, the free radicals generating from the outer channels have to be eliminated by diffusing. For this reason, it has comparatively bad cleaning efficiency. Furthermore, we also investigate the oxidizing of vanadium in the confined space. Vanadium is a very good catalyst in the oxidizing. Especially, the oxidizing of Aromatic compounds commands excellent effects. But its catalytic activity is often influenced by different varieties of coordination types and coordination ligands. Hereby, we separately coordinate the vanadium on amine modified MCM-41 and Silica gel. We can therefore compare the influences of channels on different types of products. In this way, we can gain the products we expect. And because of the different modified densities of amine on these two silicons, they will have different coordination types. By changing the coordination solvent, we can have diverse kinds of coordination ligands. We can also change the charge number of vanadium, and through the different charge number we can get different catalytic mechanisms. By the study of EPR, we can find the coordination type, catalyst mechanism, and the best catalyst condition. To sum up, we can create the most active catalyst.