The effect of monolith structure and monolith reactor inner diameter on the residence time distribution (RTD), and the relationship between RTD and the catalytic efficiency of the asymmetric aldol addition reaction between p-nitrobenzaldehyde and cyclohexanone were examined. A monolith column containing L-proline as a catalyst was prepared using poly(ethylene glycol) (PEG) as the porogen. The monolith column prepared with PEG with a molecular weight of 6000 Da displayed a narrow pore size distribution and showed a controlled RTD. The performance of monolith reactors with different inner diameters (micro- and millireactors, 0.53 and 4.00 mm) was compared: the microreactor displayed a narrower RTD and a higher turnover number for the asymmetric aldol addition reaction than the millireactor. The different linear flow velocities in the microreactor did not affect the catalytic reaction efficiency and enantioselectivity, demonstrating that the RTDs can be controlled regardless of the flow velocity.

中文翻译：

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微流反应器直径对L-脯氨酸固定聚合物整料缩合反应影响的研究

考察了整体结构和整体反应器内径对停留时间分布（RTD）的影响，以及RTD与对硝基苯甲醛与环己酮不对称醛醇加成反应催化效率之间的关系。包含L的整体柱-脯氨酸作为催化剂使用聚（乙二醇）（PEG）作为致孔剂制备。使用分子量为 6000 Da 的 PEG 制备的整体柱显示出狭窄的孔径分布和受控的 RTD。比较了具有不同内径（微型和毫反应器，0.53 和 4.00 毫米）的整体反应器的性能：与毫反应器相比，微型反应器显示出更窄的 RTD 和更高的不对称醛醇加成反应的周转数。微反应器中不同的线性流速不会影响催化反应效率和对映选择性，表明无论流速如何都可以控制 RTD。