FORMATION OF MESOPORES IN PHENOLIC RESIN-DERIVED CARBON-FIBER BY CATALYTIC ACTIVATION USING COBALT

Preparation of an activated carbon fiber containing mesopores was atte mpted by catalytic activation using cobalt. Phenolic resin and cobalt- acetylacetonate were mixed intimately, spun, cured, carbonized at 900 degrees C in nitrogen and finally activated at 750-900 degrees C in st eam. The carbon fibers with the cobalt contents of 38 ppm and 100 ppm were prepared together with a fiber without cobalt as a reference. The cobalt deposited a characteristic turbostratic carbon by catalytic gr aphitization at carbonization process. Simultaneously the cobalt accel erated activation of the fiber in steam catalytically to form mesopore s preferentially. The maximum surface area, 170 m(2)g(-1), for mesopor es of several 10s of nm in radius was obtained in the fiber containing 38 ppm cobalt after 38% burn-off. This fiber also contained a relativ ely large amount of micropores. No damage on the fiber surface after a ctivation was observed by scanning electron microscopy, but the fiber became fragile. The formation mechanism of mesopores is discussed brie fly.