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The H 2 S removal capacity of copper loaded on a number of titanosilicate supports was investigated. Copper supported on Engelhard Titanosilicate-2 (Cu-ETS-2) has been found to be a superior H 2 S scavenger for maintaining H 2 S levels below 0.5 ppm because of its high cation exchange capacity and copper dispersion. Cu-ETS-2 demonstrated higher utilization at room temperature when compared to fully developed commercial H 2 S adsorbents. In addition it was found that the adsorption capacity of Cu-ETS-2 is maintained over a wide range of activation temperatures.

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The H2S breakthrough capacity of copper-exchanged Engelhard Titanosilicate-2 (ETS-2) was measured at temperatures up to 950 °C and it was found that the adsorbent efficiency remains unchanged across the entire temperature range. Below 750 °C, the adsorption capacity at breakthrough is 0.7 mol of H2S per mole of copper while above 750 °C the capacity of the adsorbent is halved. The change in H2S capacity is due to Cu2+ reduction by the H2 which is formed through the thermal dissociation of H2S. The adsorbent shows good potential for use over a wide range of operating temperatures in H2S scrubbing processes.

in Wiley Online Library (wileyonlinelibrary.com).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 silverexchanged Engelhard Titanosilicate-10 (ETS-10), indicates that this molecular sieve is promising as an adsorbent capable of producing high-purity oxygen. High-purity oxygen (99.7þ%) was generated using a bed of Ag-ETS-10 granules to separate air (78% N 2 , 21% O 2 , 1% Ar) at 25 C and 100 kPa, with an O 2 recovery rate greater than 30%. V V C 2012 American Institute of Chemical Engineers AIChE J, 59: 982-987, 2013 Compressed air (a mixture of 78% N 2 , 21% O 2 and 1% Ar) was introduced into a column containing 130 g of pelletized Ag-ETS-10 (sieved to a size between 0.28-0.84 mm) at a flow rate of 126 mL/min (bed volume 150 mL). Composition of the outlet gas was determined by GC analysis.

Titanium silicate molecular sieves contain structural units that are fundamentally different from classical aluminosilicates. In addition to ordered octahedral titanium chains, members of the zorite family contain pentagonal titanium units which project into the main adsorption channels of the framework. We report that the effective pore size of these materials can be controlled by substituting halogens at the O7 sites that cap the pentagonal pyramids projecting into the channel. The quantity and type of halogen used determines the adsorptive properties of the molecular sieve. Barium exchange stabilizes these materials over a wide temperature range (nominally 200-400 degrees C). The barium-exchanged materials do not contract appreciably with calcination, as is observed in related Molecular Gate materials, and thus halogen content can control the pore size of the materials. This new approach to pore size control may have important implications for the purification of multiple classes of compounds, including light hydrocarbons and permanent gases.