Sol-gel (template) synthesis of macroporous Mo-based catalysts for hydrothermal oxidation of radionuclide-organic complexes

摘要

Abstract Molybdenum compounds are industrially demanding as heterogeneous catalysts for oxidation of various organic substances. Highly porous structure of molybdenum-containing catalysts avoids surface's colmatation and prevents blocking catalytic sites that makes these materials play a key role in processes of hydrothermal oxidation of radionuclide organic complexes. The study presents an original way of sol-gel synthesis of new macroporous molybdenum compounds using “core-shell” colloid template (polymer latex) as poreforming agent. We have described three individual routs of template removal via thermal decomposition to obtain porous materials based on molybdenum compounds. Thermal treatment conditions (temperature, gaseous atmosphere) have been studied with respect to their influence on composition, structure and catalytic properties of synthesized molybdenum systems. The optimal way to synthesis of crystal molybdenum (VI) oxide with ordered porous structure (mean pore size 100–160?nm) has been suggested. Catalytic properties of macroporous molybdenum materials have been investigated in the process of liquid phase and hydrothermal oxidation of such organic substances thiazine and stable Co-EDTA complex. It was shown that macroporous molybdenum oxides could be applied as prospective catalysts for hydrothermal oxidation of organic radionuclide complexes during the processing of radioactive waste. Graphical abstract The original sol-gel (template) synthesis of novel macroporous (mean pore size 100–160?nm) Mo-based catalysts for liquid phase oxidation of radionuclide-organic complexes under hydrothermal conditions has been suggested. Display Omitted Highlights ? Sol-gel (template) synthesis of macroporous Mo-based materials is described. ? Commercial siloxane-acrylate latex was used as porefoming agent. ? Composition/structure/properties are studied depending on template thermal removal. ? An optimal synthesis way of MoO3-ordered macroporosity (100–160?nm) is suggested.