Carbon Black. II—The Role of Oxygen
Abstract The results reported in this paper confirm the indication of previous work that a portion of the oxygen in carbon black exists in rather definite chemical combinations on the surface of a hydrocarbon with a high carbon-hydrogen ratio. It is not clear yet whether all of the oxygen in carbon black exists in this state, as previous work has shown that after heating for extended periods at 955° C. there still remains a small amount of oxygen in the black. It has been shown that the oxygen attached as here described does not exist in the state of gaseous adsorption and cannot be removed by heat alone as oxygen, but can be removed by reaction with zinc dust at temperatures below that at which gaseous evolution usually takes place. The oxygen goes over to zinc oxide and the volatile matter of the residue is considerably reduced.