Technology Unit

Alkaline Water Electrolyzer has the following key components:^[1]
⚗️ 𝗔𝗹𝗸𝗮𝗹𝗶𝗻𝗲 – About 25 – 30 wt% of alkaline (KOH) is used along with purified water as a feed to both sides of the electrolyzer. Increasing KOH concentration improves conductivity and lowers voltage requirements, but must be balanced with its corrosivity.
➕ 𝗔𝗻𝗼𝗱𝗲 – OH⁻ ions from the KOH is converted into Oxygen (O₂), Water (H₂O) and Electrons (e⁻) by the typically Nickel-based Anode.
⚡ 𝗘𝗹𝗲𝗰𝘁𝗿𝗶𝗰𝗶𝘁𝘆 – Commonly wind or solar power provides the current and moves the electrons from the Anode to the Cathode.
➖ 𝗖𝗮𝘁𝗵𝗼𝗱𝗲 – The Nickel-based Cathode converts water and electrons into the hydrogen product and OH⁻ ions.
⬅️ 𝗗𝗶𝗮𝗽𝗵𝗿𝗮𝗴𝗺 – The highly ionic conductor allows movement of OH⁻ through the diaphragm while minimizing product crossover.
💧 𝗦𝗲𝗽𝗮𝗿𝗮𝘁𝗼𝗿𝘀 – KOH and Water is recovered from the Oxygen and Hydrogen streams, which are then cooled and recycled back to the AWE Electrolyzer.
🧱 𝗦𝗶𝗱𝗲 𝗦𝗲𝗴𝗿𝗲𝗴𝗮𝘁𝗶𝗼𝗻 – The hydrogen and oxygen sides are often segregated to further minimize product crossover. As hydrogen is extremely combustible in the presence of oxygen, crossovers can create a hazardous environment.

1. Joaquim Tsu, Bryan Research & Engineering, LLC, Jan 2023, Linkedin, https://www.linkedin.com/posts/activity-7016236527051579393-M0PZ