Catalyst leaching is a major impediment to the development of commercially-viable processes conducted in a liquid-phase. To date, there is no reliable technique that can accurately identify the extent and dynamics of the leaching process in a quantitative manner. In this work, a tandem flow-reactor system has been developed, which allowed us to distinguish between surface-catalyzed reactions from those occurring in solution by comparing%conversion at the exit of each reactor (S1, S2) corresponding to predominance of heterogeneous/homogeneous reactions (spatial) and two different residence times (temporal). A multiscale model is subsequently established to quantify the two types of reaction rate and simulate the catalyst leaching from a cross-coupling catalyst, PdEncat™ 30; including: (1) a multi-particle sizes model for catalyst scale; and (2) a dispersion model for reactor scale. The results show that catalyst leaching occurs via more than one process, and that the homogeneous Pd-catalyst (leached from the immobilized catalyst and dissolved in the flow) dominates the reaction and possesses a much higher activity than the heterogeneous (immobilized) Pd-catalyst. Additionally, the change of leached Pd stream inside reactors can be predicted along with the axial direction and the reaction time through the reactor-scale dispersion model.

催化剂浸出是在液相中进行商业上可行的方法开发的主要障碍。迄今为止，还没有可靠的技术可以定量地准确识别浸出过程的程度和动力学。在这项工作中，已经开发了串联流动反应器系统，该系统使我们能够通过比较每个反应器出口处的转化率（S1，S2）将表面催化反应与溶液中发生的反应区分开来。）对应于异质/均质反应的优势（空间）和两个不同的停留时间（时间）。随后建立了一个多尺度模型，以量化两种反应速率并模拟从交叉偶联催化剂PdEncat™30中浸出的催化剂。包括：（1）催化剂规模的多粒度模型；（2）反应堆规模的分散模型。结果表明，催化剂浸出是通过不仅是一个以上的过程，而且均相Pd催化剂（从固定化催化剂中浸出并溶解在物流中）支配了反应，并且比非均相（固定化）Pd催化剂具有更高的活性。此外，通过反应器规模分散模型，可以预测反应器内部浸出的Pd物流的变化以及轴向和反应时间。