(113e) Improved Process for Ultra-High Purity Nitrogen Production

Production of UHP Nitrogen is critical for many electronic processing facilities. Previous technology for combined CO/H₂ removal from air utilized a separate reactor vessel and economizer located after the main air compressor for oxidation of CO and H₂ to CO₂ and H₂O. These were then removed in the TSA unit, yielding a purified air stream essentially free of CO, H₂, CO₂, and H₂O. Drawbacks, however, include the requirement of relatively high reactor temperatures (and associated heating equipment), use of a very expensive noble metal-based catalyst, use of an expensive aluminum plate fin economizer and the cost of the separate reactor vessel.

A novel, lower cost approach has been developed for removing both H₂ and CO from air by incorporating a layer of metal oxide catalyst in the TSA unit. It is placed after the alumina and zeolite layers (which are used to remove water and CO₂ from the air). Under the low water, low CO₂ conditions the catalyst can oxidize CO and H₂ and simultaneously adsorb the produced water and CO₂. Development efforts and commercial application opportunities will be highlighted in this talk.