Separation

Separation is where electrochemistry stops being just a redox reaction and starts being a process — the step that decides what leaves the cell, in what concentration, and at what energy cost. This section of the catalog groups the two electro-driven separation disciplines that share hardware, materials, and operating principles with the rest of the EChem stack: gas capture and separation on one side, and ion separation on the other.

Both disciplines replace thermal or pressure-swing duty with applied potential, and both lean on the same material families that power fuel cells, electrolyzers, and flow batteries — sulfonated PFSA and hydrocarbon ionomers, anion-exchange polymers, bipolar laminates, polyolefin and ceramic-reinforced separators, gas diffusion layers with integrated microporous layers, and porous current collectors. What differs is the target species and the cell format.

• Gas Capture and Separation — electrochemically mediated capture using redox-active sorbents (quinones, bipyridiniums, metal-amine complexes), ion-conducting membranes for gas-phase selectivity, and direct electrocatalytic conversion that blurs the line between separation and CO2 reduction. Cell formats borrow from PEM and AEM electrolyzer architectures and from redox flow battery hardware.
• Ion Separation — the membranes and benchtop testing cells used for electrodialysis (ED), electrodeionization (EDI), capacitive deionization (CDI and FCDI), bipolar-membrane electrodialysis (EDBM), and reactive CO2 capture coupled to electroreduction. Cation-exchange, anion-exchange, and bipolar membranes are paired with FCDI stacks, PSE reactors, and optically accessible flow electrolyzers.

If you are working on CO2 capture or O2/N2 selectivity, start in Gas Capture and Separation. If you are screening salt removal, acid-base generation, or ion-selective transport, start in Ion Separation. For the broader ion-conducting membranes used inside fuel cells, electrolyzers, and flow batteries — rather than as the selective layer of a separation stack — see Membranes and MEA.