We provide a theoretical background on laminar flow electrochemical reactors and rationally map typically encountered operating regimes in literature. At the highest (mass transfer limited) current densities attainable, the Fourier number (Fo) and the Sherwood number (Sh) are identified as important dimensionless groups for design considerations. The critical Fourier number places a severe constriction on the production capacity of a microreactor, as it determines the maximum throughput for a reactor of fixed length and inter-electrode distance. This critical Fourier number indicates that the absence of convective mixing and the reliance on diffusion of the electroactive species is the key problem to address for further intensifying electrochemical microreactors. Computer simulations are then used to illustrate the steady-state as well as transient behavior of generic case studies. These simulations also show that the transient response to a voltage step can be used to experimentally verify that the absence of mixing is a major bottleneck of laminar flow reactors. A versatile tubular electrochemical reactor was developed and applied to an acetonitrile solution containing ferrocene and benzylbromide, which is a simple model system for investigating self-supported synthesis (i.e., electrosynthesis without intentionally added supporting electrolyte). The reactor was then fitted with piezoelectric elements that excite a resonating standing wave in the flow direction, resulting in pairs of counter-rotating vortices in the fluid (acoustic streaming). The sonicated experiments prove that ultrasound assisted mixing reduces the critical Fourier number, enabling self-supported synthesis at elevated flow rates and throughput.

我们提供了层流电化学反应器的理论背景，并合理地映射了文献中通常遇到的运行方式。在达到最高电流密度（受传质限制）的情况下，出于设计考虑，傅立叶数（Fo）和舍伍德数（Sh）被确定为重要的无量纲组。临界傅立叶数严重限制了微反应器的生产能力，因为它决定了固定长度和电极间距离的反应器的最大产量。该临界傅立叶数表明，不存在对流混合并且依赖于电活性物质的扩散是为进一步增强电化学微反应器而解决的关键问题。然后使用计算机仿真来说明常规案例研究的稳态和瞬态行为。这些模拟还表明，对电压阶跃的瞬态响应可用于实验验证混合的不存在是层流反应器的主要瓶颈。开发了一种通用的管式电化学反应器，并将其应用于包含二茂铁和苄基溴的乙腈溶液，这是研究自支撑合成的简单模型系统（即电合成，而无需有意添加支持电解质。然后，反应器装有压电元件，该压电元件在流动方向上激发共振驻波，从而在流体中产生成对的反向旋转涡流（声流）。超声处理的实验证明，超声辅助混合可降低临界傅立叶数，从而能够在提高的流速和通量下进行自支撑合成。