Dynamic Liquid–Liquid Interface: Applying a Spinning Interfacial Microreactor to Actively Converge Biphasic Reactants for the Enhanced Interfacial Reaction

Abstract

A liquid–liquid interfacial reaction combines reactants with large polarity disparity to achieve greener and more efficient chemistry that is otherwise challenging in traditional single-phase systems. However, current interfacial approaches suffer from the need for a large amount of solvent/reactant/emulsifier and poor reaction performance arising from intrinsic thermodynamic constraints. Herein, we achieve an efficient interfacial reaction by creating a magnetic-responsive, microscale liquid–liquid interface and exploit its dynamic spinning motion to generate vortex-like hydrodynamic flows that rapidly converge biphasic reactants to the point-of-reaction. Notably, the spinning of this functional interface at 800 rpm boosts the reaction efficiency and its apparent equilibrium constant by > 500-fold and 105-fold, respectively, higher than conventional methods that utilize bulk and/or non-dynamic liquid interfaces, even with external mechanical stirring. By driving reaction equilibrium toward favorable product formation, our unique design offers enormous opportunities to realize efficient multiphasic reactions crucial for diverse applications in chemical synthesis, environmental remediation, and even molecular recycling.

Capillarity in Interfacial Liquids and Marbles: Mechanisms, Properties, and Applications

“…Liquid marbles, which are constructed at the air-solid or air-liquid interface, have found substantial applications in miniaturized microreactors and microbioreactors [40][41][42][43], demonstrating unique features such as high interfacial area [44], oxygen permeability [45], tunable shell function [46], and stimuli-responsiveness upon applied potential and heat [47]. Compared to liquid marbles, interfacial liquid marbles may obtain extraordinary morphology and composition stability, durability, self-assembly, and transparency; the presence of the upper liquid phase may seal the interfacial liquid marbles with the ambience, prohibiting the evaporation of the encapsulated liquid and lowering the oxygen concentration at the surface of the marbles, making the marbles ideal microreactors for investigating reduction reactions.…”

Building Functional Liquid‐Based Interfaces: From Mechanism to Application

“…In another example, Lee and co-workers achieved efficient interfacial reactions by creating a magnetic-responsive liquid/liquid interface. [14] The spinning motion generated vortex-like hydrodynamic flows that converged biphasic reactants to the point-of-reaction at the dynamic interface, subsequently improving the reaction efficiency (> 500-fold) and the apparent equilibrium constant (up to 10 5 -fold).…”

“…In the 1,2‐dichloroethane (DCE), a more hydrophilic anion of salt [Y] would lead to a more rapid formation of o/w droplets, while larger carbon chains of salt [X] did not provide the necessary activation for reaction (Figure 1d). In another example, Lee and co‐workers achieved efficient interfacial reactions by creating a magnetic‐responsive liquid/liquid interface [14] . The spinning motion generated vortex‐like hydrodynamic flows that converged biphasic reactants to the point‐of‐reaction at the dynamic interface, subsequently improving the reaction efficiency (>500‐fold) and the apparent equilibrium constant (up to 10 5 ‐fold).…”