Catalysis Today, Vol.150, No.1-2, 77-83, 2010
Properties of CMK-8 carbon replicas obtained from KIT-6 and pyrrole at various contents of ferric catalyst
The CMK-8 carbons were synthesised using two KIT-6 silica matrices exhibiting well-ordered structures. With increasing synthesis temperature, the BET surface area and micropore volume diminished while the average size of mesopores increased. Among the replicas of KIT-6(120), the one synthesised using the largest amount of FeCl(3) (2.00 g/g silica) showed the best structure ordering. The opposite trend was observed for carbons derived from KIT-6(1 0 0): the replica prepared with use of 0.75 g FeCl(3)/g Silica exhibited the best structure ordering, reflected in the narrowest pore size distribution (centred at 4.3 nm), a(0) = 20.54 nm, and S(BET) = 1313 m(2)/g. This was due to an appropriate geometric relationship between the pore size and wall thickness of the matrix. The replicas of KIT-6(120) appeared to have a more homogenous pseudo-graphitic character. All the replicas exhibited high catalytic activity in oxidation of SO(2) in a liquid phase. The catalytic activity process does not directly correlate with the total nitrogen content; it relates to nitrogen of the quaternary type and depends on external surface areas of the samples studied. (C) 2009 Elsevier B.V. All rights reserved.
Keywords:Carbon replicas;KIT-6;Ordered mesoporous materials;Nitrogen-containing carbons;Sorption properties;FeCl(3) catalyst;Liquid phase SO(2) oxidation