PEM Electrolysis
PEM electrolysis splits purified water across a solid proton-conducting polymer membrane, giving separated hydrogen and oxygen streams without a liquid alkaline electrolyte.
- Proton transport occurs through a solid polymer rather than a liquid KOH solution.
- Anode and cathode gas streams are separated by the membrane itself.
- Current density sets production rate, enabling fast modulation.
Mechanism
The membrane electrode assembly is compressed between flow fields. Deionised water is fed to the anode; protons cross the membrane and recombine with electrons at the cathode. Gas is separated at the cell rather than downstream.
PEM purity
There is no dissolved alkali to entrain, so gas leaving the stack carries moisture rather than caustic mist. That distinction is the principal purity difference against alkaline systems.
- PEM: solid electrolyte, deionised water, no caustic carry-over.
- Alkaline: liquid KOH electrolyte, potential aerosol carry-over requiring scrubbing.
Production
PEM stacks tolerate rapid load changes and low turn-down, which suits duty cycles that follow equipment operation rather than a fixed baseload.
Industrial and consumer applications
The same electrolysis principle underlies industrial supply to combustion equipment and consumer modality equipment; only scale, conditioning and regulatory context differ.
Reference material only. CE Global publishes hydrogen production and PEM electrolysis engineering information. Nothing here is a medical, health, performance, emissions or fuel-saving claim.