Production of Argon Free Oxygen by Adsorptive Air Separation on Ag-ETS-10

The purification of different components of air, such as oxygen, nitrogen, and argon, is an important industrial process. Pressure swing adsorption (PSA) is surpassing the traditional cryogenic distillation for many air separation applications, because of its lower energy consumption. Unfortunately, the oxygen product purity in an industrial PSA process is typically limited to 95% due to the presence of argon which always shows the same adsorption equilibrium properties as oxygen on most molecular sieves. Recent work investigating the adsorption of nitrogen, oxygen and argon on the surface of silver-exchanged Engelhard Titanosilicate-10 (ETS-10), indicates that this molecular sieve is promising as an adsorbent capable of producing high-purity oxygen. High-purity oxygen (99.7+%) was generated using a bed of Ag-ETS-10 granules to separate air (78% N-2, 21% O-2, 1% Ar) at 25 degrees C and 100 kPa, with an O-2 recovery rate greater than 30%. (C) 2012 American Institute of Chemical Engineers AIChE J, 59: 982-987, 2013