Fluka's gamma-Al2O3, 130 M-2/g, was wet-impregnated with Co(NO3)(2)(.)6H(2)O, kept 24 h/room temperature, dehydrated, dried 4 h/105degreesC, and calcined 3 h/350degreesC in air to yield a 3.5%Co/Al2O3 catalyst that was reduced 1 h/500degreesC with H, and used to crack C3H8 1 h/400degreesC to deposit C. This C was shown by (i) TP oxidation and (ii) TP surface reaction (with 142) techniques to have built up as amorphous and graphitic entities that were removed at max. formation rates of (i) CO2 at 435 and 535degreesC and (ii) of CO (in H-2) at 610 and 805degreesC (and of CH4 at 585degreesC). The removal was (i) nearly 100% (up to 650degreesC) and (ii) 23% only (up to 900degreesC).