Oxygen and PSA
Zirconia oxygen analyser
A zirconia oxygen analyser measures oxygen with a sensor based on zirconia, an oxygen-ion-conducting solid electrolyte; in the potentiometric type described by Dietrich et al. (Sensors, 2021), the voltage between two electrodes, the Nernst voltage, measures the difference in oxygen partial pressure between a sensing electrode and a reference electrode.
Dietrich, Kusnezoff and Michaelis (Sensors, 2021) note that potentiometric sensors based on zirconia solid electrolytes have been widely used for more than four decades to determine oxygen content in automotive applications and industrial processes. Platinum or platinum-based cermets serve as electrodes in many applications, the ionic conductivity of the zirconia is typically enhanced with metal oxides such as yttria, and the article describes operation at a sufficiently high temperature of 350 to 950 °C. For a reproducible measurement in a sample gas, one electrode must provide a stable reference potential.
In medical oxygen generation, NHS England's HTM 02-01 (2026) specifies paramagnetic instruments: a duplex calibrated paramagnetic oxygen monitoring system for PSA plants, and a paramagnetic analyser for oxygen identity tests.
Ultra Controlo analysers
The ULTRAOX SC datasheet lists one or two oxygen analysers with a zirconium oxide probe.
Sources
- Dietrich S, Kusnezoff M, Michaelis A. Studies of Indium Tin Oxide-Based Sensing Electrodes in Potentiometric Zirconia Solid Electrolyte Gas Sensors. Sensors (Basel) 2021;21(7):2345, introduction
- ULTRAOX SC datasheet, p. 2
- NHS England, HTM 02-01 Part A (2026), paragraphs 6.121 and 20.48
Ultra Controlo figures come from its technical datasheets. Third-party facts were read at the source on the date shown.