Reaction of Dry Cobalt Powders with CO

6065 g sample of this powder was treated with CO (1130psi) at room temperature. The pressure dropped immediately, reaching 700psi in 5 min with a large exotherm that made the bomb intolerably hot to the touch. Visual examination of the sample after the bomb was vented showed no obvious change in the powder. The sample was then repressurized to lOOOpsi at room temperature. After 10 min, the pressure stabilized at 955 psi with no obvious exotherm. The bomb was placed in an 87°C oil bath for 2 h and then cooled and 

Hydrolysis with concentrated hydrochloric acid, of samples before and after treatment with CO, gave 9.0 and 8.0 mmol of gas/g, respectively. The hydrocarbons are shown in Table 15.2, runs 3 and 4. 

From hydrolysis of the carburized samples was obtained a finely divided black material that represented 29.89% of the sample mass. Ignition of this material resulted in a 95-99% decrease in mass and was accomplished with the formation of a small quantity of a refractory material. 

In similar experiments CO2 was shown to be present in the gases vented from the reactor by precipitation of CaCOs from a saturated Ca(OH)2 solution through which the gases were dispersed. 

Debye-Scherrer photographs of cobalt from this preparation before CO treatment, after CO treatment, and after annealing at 300°C for 14 h under argon were obtained. Analysis of these films was inconclusive the calculated interplanar distances being in poor agreement with known metallic oxidic or carbidic phases (see Table 15.3). 

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