Combustion of volatile organic compounds over Cu-Mn based mixed oxide type catalysts supported on mesoporous Al2O3, TiO2 and ZrO2

A series of supported Cu-Mn based catalysts have been synthesized using three different supports mesoporous Al2O3, mesoporous TiO2 and mesoporous ZrO2. Cu-Mn precursors were incorporated on mesoporous supports using wet impregnation method. These catalyst supports were prepared by templating method using a natural biopolymer namely, chitosan. The catalytic activity for benzene and acetaldehyde combustion was studied for these catalysts. The synthesized catalysts have been characterized by XRD, BET-SA, O-2-TPD and H-2-TPR in a view of material characterization, as well as to investigate the mechanistic aspects of catalytic reactions. The bimetallic supported catalysts follow the activity sequence-Cu-Mn/TiO2 > Cu-Mn/ZrO2 > Cu-Mn/Al2O3 for both the reactions studied. These results interestingly show, that the catalytic activity is dependent on the support used, however, quite independent of the surface area of these supports. The better activity of TiO2 and ZrO2 based catalysts is likely due to their redox properties. The existence of low temperature peaks in both O-2-TPD and H-2-TPR explain better redox properties as well as catalytic performance of TiO2 and ZrO2 supported catalysts as compared to those Al2O3 supported mixed oxides. (C) 2012 Elsevier B.V. All rights reserved.