A Multi‐Stream Microchip for Process Intensification of Liquid‐Liquid Extraction

Solvent extraction is a critical step in many industrial mineral‐processing circuits and is affected by chemical (e.g., metal ions, extractant, pH, reaction rate) and physical (e.g., interfacial phenomena, mass transport, temperature) factors. Here, a new type of microfluidic contactor is presented that enables higher volumetric throughputs and straightforward counter‐current operation compared with Y‐Y chips. A single chip design can handle a wide range of organic/aqueous phase ratios, thereby enabling stable operation for non‐ideal solutions and fluctuating flow. An expression defining this widened operational window has been derived based on the relative stream geometries and liquid viscosities. A two‐stage counter‐current circuit is demonstrated for the extraction of platinum(IV) chloride.