Abstract: Carbon black is produced by introducing a carbon black feedstock, along with hot combustion gases, into the reaction zone of a carbon black furnace where the feedstock is partially burned and thermally decomposed to form carbon black. A hydrogen donor, such as ammonia gas, is simultaneously introduced into the reaction zone of the furnace from an extraneous source. The added hydrogen reduces the rate at which the carbon black feedstock is dehydrogenated. Carbon black aggregates produced in the reaction zone have surfaces characterized by reduced crystallite formation and an increased presence of amorphous carbon. The hydrogen content of the carbon black is also increased. This reduces the surface activity of the carbon black, making it more readily dispersible in elastomers, and improves the properties of such rubber compounds.