| abstract |
The invention relates to heterogeneous catalysts comprising an organo-ruthenium complex immobilized to an aluminum-modified inorganic oxide by a chemical bond between a tetra-coordinated aluminum atom on a surface of the aluminum-modified inorganic oxide and an amino or imino nitrogen of the organo-ruthenium complex, methods of preparing the heterogeneous catalysts including immobilizing the organo-ruthenium complex to a tetra-coordinated aluminum atom on a surface of an inorganic oxide by reacting an amino or imino nitrogen of the organo-ruthenium complex and an aluminum-modified inorganic oxide, followed by a defined heat treatment, as well as methods for producing hydrogen from formic acid using the heterogeneous catalysts. |