MCM-41 modified with iron by template ion-exchange method as effective catalyst for DeNOx and NH3-SCO processes

摘要

Iron was deposited on MCM-41 using template ion-exchange (TIE) method. Solutions of FeCl2 and [Fe-3(OAc)60(H2O)(3)]NO3 were used as precursors of deposited iron species. It was shown that deposition of significant amount of iron, in some cases above 10 wt.% in recalculation to Fe2O3, on MCM-41 or TiMCM-41 resulted only in a relatively small decrease of the specific surface area and porosity of the mesoporous silica supports. Moreover, in case of iron acetate oligocations deposition, the formation of iron oxide micro-rods outside of the MCM-41 structure was found. Such effect was not observed when a solution of FeC12 was used for iron deposition. MCM-41 and Ti-MCM-41 modified with iron by TIE method were found to be active catalysts for the process of the selective oxidation NH3 to N-2 (NH3 SCO). In this process, the catalysts effectively operated in the high -temperature range with a very high selectivity to dinitrogen (above 90% at 550 degrees C). Some differences in catalytic performance, related to type of the mesoporous support as well as iron loading and precursor used for deposited iron species, were observed. (C) 2016 Elsevier B.V. All rights reserved.