We investigated the possibility of synthesizing Co nanoparticles in CoZrH/AlO(OH)/Al ceramic-metal catalysts and controlling the catalytic properties of these nanoparticles in syngas conversion by changing the Co/Zr ratio. The CoZr nanocomposites were obtained from metal powders by mechanochemical activation in a high-energy mill under an argon atmosphere, followed by treatment with hydrogen at high pressure and room temperature. Ceramic-metal catalysts were prepared by mixing the corresponding CoZrH powder nanocomposite (30 wt%) with powdered aluminum (70 wt%), hydrothermal treatment of the mixture and subsequent calcination.
View Article and Find Full Text PDFBiocatalytic engineering was carried out by varying monotonically the binary CNTs-silica composition and, accordingly, the physicochemical characteristics of adsorbents developed for immobilization of recombinant T. lanuginosus lipase (rPichia/lip). The adsorbents based on composite carbon-silica materials (CCSMs) were produced by impregnating finely dispersed multi-walled carbon nanotubes with silica hydrosol followed by calcination in argon at 350°C; the mass ratio of the hydrophobic and the hydrophilic components varied over a wide range.
View Article and Find Full Text PDFThe use of metal powders produced by mechanical treatment in various fields, such as catalysis or gas absorption, is often limited by the low specific surface area of the resulting particles. One of the possible solutions for increasing the particle fineness is hydrogen treatment; however, its effect on the structure of mechanically treated powders remains unexplored. In this work, for the first time, a metal-oxide nanocomposite powder was produced by mechanical alloying (MA) in a high-energy planetary ball mill from commercial powders of Zr and Co in the atomic ratio Co:Zr = 53:47 in an inert atmosphere, followed by high-pressure hydrogenation at room temperature.
View Article and Find Full Text PDFIn the present work, complex powder alloys containing spinel as a minor phase were produced by mechanical alloying in a high-energy planetary ball mill from a 33Al-45Cu-22Fe (at.%) powder blend. These alloys show characteristics suitable for the synthesis of promising catalysts.
View Article and Find Full Text PDF