Stephan Klein

Amorphous microporous mixed oxides as selective redox catalysts

Amorphous microporous homogeneously mixed oxides based on Ti or V in silica can be prepared by an acid catalyzed solgel process. The materials have been characterized by TEM, UV, IR and sorption methods. The glasses can be used for the selective epoxidation of alkenes. The catalytic properties are comparable to those of the well known crystalline Ti-containing zeolites TS-1, Ti-MCM-41 and Ti-Beta. Amorphous microporous homogeneously mixed metal oxides seem to be promising new catalytic materials supplementing the well studied selective zeolites.

Selective heterogeneous epoxidations with Cp-titanium chloride derived microporous silica glasses

Abstract A new heterogeneous epoxidation catalyst is prepared by the copolycondensation of cyclopentadienyl titanium chlorides with tetraethoxysilane by a modified sod-gel procedure. Epoxidations of non-activated olefins in the presence of these new heterogeneous catalysts are described.

Sol-Gel Methods for the Production of Novel Catalytic Materials

Ecological as well as economical aspects influence the development of chemical processes. To meet the increasing regulations new heterogeneous catalysts are required, which should improve selectivity and utilize cheaper feedstocks. Zero waste processes are a clear goal of the chemical industries [1]. Most “new” catalysts will be based on gradual improvements of known materials, but there is a demand for new catalysts with properties different from those of the known catalytic materials. Among the “new” catalysts of the past that have successfully replaced traditional catalytic materials, zeolites, bimetallic and bifunctional catalysts might be mentioned.