Molecular dispersion of metal complexes within zeolitic solids: An alternative way to prepare supported MOx catalysts

Molecular Designed Dispersion (MDD) of metal complexes on a highly porous s upport is a novel synthesis method to prepare high quality heterogeneous ca talysts. The process basically consists of two steps: (1) the anchoring of the complex onto the support in a controlled way and (2) the mild oxidation of the grafted complex towards catalytically active metal-oxide surface st ructures. This article presents two typical case studies: (1) the incorporation of ca tionic Cu-complexes in a H-ZSM-5 zeolite from the liquid phase and (2) the gas phase modification of pure silica MCM-48, using the VO(acac)(2) complex . In both cases, superior catalysts are obtained. Detailed chemical, physic al and catalytical analyses of these catalysts are discussed in the text. C omparison is made with analogous catalysts, prepared by conventional method s.