Preparation and characterization of aluminosilicate supports with a synthesized layer of catalytic filamentous carbon: II. Synthesis of carbon nanofibers on a supported cobalt catalyst

Abstract

The synthesis of a layer of catalytic filamentous carbon (CFC) on a Co catalyst supported by homogeneous precipitation onto the surface of aluminosilicate supports (ceramic foam and vermiculite) was studied. The effects of CFC layer synthesis conditions (the catalyst concentration on a support, the pyrolysis temperature of a propane-butane mixture, and the composition of the gas mixture) on the specific surface areas of supports, the yield of carbon (g C)/(g Co)), and the morphology of a surface CFC layer were examined. It was found that, in the case of ceramic foam, the concentration of cobalt hydroxide precipitated on the surface was lower by a factor of 15 and the yield of carbon was higher by a factor of 20–40 than those in vermiculite. The specific surface areas of supports, the yield of carbon, and the amount of synthesized carbon increased as the pyrolysis temperature of a propane-butane mixture was increased from 500 to 600°C. As found by scanning electron microscopy, the carbon content increased with pyrolysis temperature because of an increase in the length of carbon nanofibers. The properties (activity and stability) of biocatalysts prepared by the adsorption immobilization of a recombinant protein having glucose isomerase activity on CFC-Co-containing supports (ceramic foam and vermiculite) were studied.