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Copper supported catalysts based on preliminary oxidized carbon fibers have been studied. Nitric acid and hydrogen peroxide have been used for prior oxidation treatment of the supports. To characterize this materials N2 adsorption-desorption and titration technics were used. Compared to nonoxidized activated carbon fibers, no significant changes in the texture of the modified supports were found, while there were differences in surface functionalities. Cupper supported catalysts were prepared by wetness impregnation and characterized by TPR, SEM. The influence of different surface functional groups on the distribution of active metal has been discussed. Besides, the catalysts were tested in the process of ethanol dehydrogenation. Cupper supported on activated carbon fibers preliminary oxidized with HNO3 appeared to be more active in the process, although less stable at high temperatures. The reasons of the loss of activity have been also discussed.

The results of a research on the influence of activation of carbon fibers in CO2 current on the change in their specific adsorptive surface and porous structure are presented. The fibers under study were produced from viscose and polyacrylonitrile. It is shown that as a result of activation the specific surface of carbon fibers can be increased from 0.3 to 1900 m2 /g, and the volume of porous space, from 0.1 to 400 cm3 /g. It is established that the nature of the initial fiber has an essential influence on the extent of change in specific surface and porous structure. After activation fibers based on viscose have significantly greater values of specific surface and a bigger fraction of micropores in their structure than fibers based on polyacrylonitrile.