Preparation and Characterization of MnxOy-Al2O3 Sorbents for H2S Removal from Biomass Gasification Gas

摘要: Abstract A series of MnxOy - Al2O3 materials have been prepared either by spray-drying (SD) Al/Mn precursor solutions or multiple wet-impregnations two different Mn precursors on various alumina supports. The used in the preparation were manganese nitrate (Mn(NO3)2.4H2O) and acetate (Mn(CH3COO)2.4H2O). To study properties relevant for sorption performance, calcined characterized using several methods. Textural (N2 sorption) loaded samples show significant differences when compared to parent For this is due relatively high loading (up 30 wt. %) additional heat treatment. sample SD it presence species that modifies textural affects way final material formed. X-ray diffraction measurements ratio Mn2O3/Mn3O4 depends are wet-impregnation method. method use a specific has no influence material. UV-Raman spectra strongly indicate MnO2 surface all sorbents. was not detected XRD. new also Raman spectroscopy their existence ascribed interaction between Al2O3. TPR data there three main reduction steps most likely MnO through intermediate Mn2O3 Mn3O4. data, however, indicates formed at temperature (above approx. 550 °C). It proposed features observed profiles might be formation spinel structure MnAl2O4.