权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Development and mechanism elucidation of novel photoreaction processes in microreactors

微反应器中新型光反应过程的开发和机理阐明

基本信息

批准号：
18510109
负责人：
MATSUSHITA Yoshihisa
金额：
$ 1.98万
依托单位：
Tokyo Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2006
资助国家：
日本
起止时间：
2006 至 2007
项目状态：
已结题

项目摘要

Photochemical reactions carried out in microreactors can be expected to exhibit some advantages, such as higher spatial illumination homogeneity and better light penetration through the entire reactor depth, and larger illuminated surface area per unit volume in comparison with those conducted in large-scale reactors. Therefore, we have developed microreactors optimized for photoreactions.Photodimerization and asymmetric photocycloaddition reactions were examined as model reactions. We observed not only the drastic increase of the quantum efficiency of the reaction, but also the enhancement of stereoselectivity in the microreaction system. In the micro-flow system, the residence time of the substrate is very short and the reaction vessel does not retain the reaction products. These facts may prevent sequential side reactions and increase the yield and selectivity of the asymmetric reaction.Photocatalytic oxidation and reduction of organic compounds, amine N-alkylation, and carbon dioxide fixation processes were investigated in the photocatalytic microreaction system. These model reactions proceeded quite rapidly with considerably large photonic efficiencies.Photocatalytic reduction of CO 2 was examined by using several sort of metal co-catalyst loaded on the TiO 2 surface. Though it has been known that CO 2 in aqueous solution can be photocatalytically reduced, only very low reaction yields were reported by using large-scale batch reaction systems. The reaction proceeded very quickly to form methanol as the main product in our microreaction system. The yield of methanol is more than 1000 times larger than that obtained in conventional batch reaction systems and further increased under multiphase flow condition.

在微反应器中进行的光化学反应可以预期显示出一些优势，例如更高的空间照明均匀性和更好的光穿透整个反应器深度，与在大型反应器中进行的反应相比，单位体积的照明表面积更大。因此，我们开发了针对光反应进行优化的微反应器。以光二聚化反应和不对称光环加成反应为模型反应。我们不仅观察到反应的量子效率大幅提高，而且微反应体系的立体选择性也增强了。在微流系统中，底物的停留时间很短，反应容器不保留反应产物。这些事实可以防止连续副反应，提高不对称反应的收率和选择性。在光催化微反应体系中研究了有机化合物的光催化氧化还原、胺n -烷基化和二氧化碳固定过程。这些模型反应进行得相当快，光子效率相当高。研究了几种载于tio2表面的金属助催化剂对co2光催化还原的影响。虽然已知水溶液中的co2可以光催化还原，但使用大规模间歇反应系统的反应产率很低。在我们的微反应系统中，反应进行得非常快，形成甲醇作为主要产物。甲醇的产率是常规间歇反应体系的1000倍以上，在多相流条件下进一步提高。