Reactive H2S chemisorption on mesoporous silica molecular sieve-supported CuO or ZnO

Natural gas, a valuable energy carrier, can be used as a fuel or as a raw material for the production of synthesis gas and hydrogen. However, significant quantities of undesirable contaminants, especially hydrogen sulfide (H2S), generate harmful environmental emissions. The objective of this work was to develop a scavenger system for the H2S removal at room temperature. The potential of mesoporous silica molecular sieve (MSU-1) supported ZnO or CuO adsorbents has been studied at room temperature for H2S removal to develop a more effective adsorbent for this important application. Zn2+ or Cu2+ loadings of 10, 20 and 30 wt.% were incorporated by the incipient wetness method. The obtained solids were characterized by X-ray fluorescence (XRF), X-ray diffraction (XRD), temperature programmed reduction (TPR), scanning electron microscopy (SEM) and N-2 adsorption/desorption, using the BET method, to investigate their various characteristics. The MSU-1 support did not show activity for H2S removal, however the addition of copper or zinc increased the removal performance. The most active solids for H2S were 10Zn/MSU-1 (42.3 mg g(-1)) and 20Cu/MSU-1 (19.2 mg g(-1)). A decrease in H2S removal was observed at a zinc loading higher than 10 wt.% (14.8 and 11.5 mg g(-1) for 20 and 30Zn/MSU-1), while 10Cu/MSU-1 presented a low adsorption capacity (10.9 mg g(-1)) and 30Cu/MSU-1 has a similar performance than that of 20Cu/MSU-1. The adsorption capacity of the obtained materials strongly depends on the pore system as well as the well-proportioned distribution of the active phase inside the porous material and the size of metal oxide nanoparticles. (C) 2012 Elsevier Inc. All rights reserved.