Vanadium and mobium species (together and separately) were loaded on gamma alumina, and the resulting catalysts were run in the methanol conversion. This reaction was studied by both GC analysis and FTIR study in the flow system. The catalytic properties are discussed based on the combined FTIR and Al-27, V-51 and H-1 MAS NMR studies. The NMR studies revealed a different mechanism of interaction between Nb and Al2O3 than that between V and Al2O3. This predetermines the structure of vanadium sites in bimetallic VNb/Al samples. The effect of coverage was considered for various metal loadings ranging from below to above monolayer. One of our most interesting findings is that the surface Nb oxide species exhibited a redox character below monolayer but were acidic above monolayer. Al-27 MAS NMR revealed a strong alumina-Nb interaction that may account for its redox performance. Moreover, the role of sulfate from vanadium precursor is evidenced. (c) 2008 Elsevier Inc. All rights reserved.