Unused 1,000 Kg/day (491 Nm3/hr) Hydrogen PSA unit, specifically designed to purify hydrogen generated from a chlor-alkali plant and can also be used for purifying hydrogen after sodium chlorate electrolysis or other electrolysis processes. Built in 2023, the system remains in its original crate and packaging, never installed, and preserved under nitrogen. The raw hydrogen gas is saturated with water and enters the purification system at a flow rate of 410 SCFM, 20°C, and 15 psig. It contains approximately 97% hydrogen, 2% oxygen, 0.2% nitrogen, 0.1% carbon dioxide, and 0.7% water. The gas is compressed in a hydrogen screw compressor to approximately 150 psig, then passes through a DeOxo unit to remove most of the oxygen content, forming water. After oxygen removal, the gas is condensed and enters a vertical water separator. The gaseous stream is sent to the Pressure Swing Adsorber (PSA) unit, where most of the impurities in the hydrogen gas, including residual O2, N2, and H2O, are removed. The product gas meets the fuel cell grade specifications SAE (Society of Automotive Engineers) Fuel Cell Gas Composition Standards. It is then sent to the downstream compression stage at a flow rate of >290 SCFM, while the waste gas is vented through the vent stack. It was later indicated that the oxygen content in the raw gas might reach a maximum of 3.5%, which would raise the DeOxo reactor unit temperature to over 500 °C. A hydrogen recycle stream is implemented to dilute the O2 entering the reactor, but this reduces the system's processing capacity.