Reaction Behavior of a Trace Element during the Pitch Pyrolysis Process

[Image: see text] The pyrolysis behavior of pitch determines the performance of pitch coke and directly affects the carbon anode air/CO(2) reactivity. The effects of pitch mass and pyrolysis rate on the pyrolysis process of pitch are studied using a self-made pyrolysis device. The effects of Na, Ca, and Mg on pyrolysis kinetics and carbon anode reactivity are also investigated. Results show that the pyrolysis of pitch on the surface and inside of the carbon anode can refer to the kinetic data of small mass asphalt (SMP) and large mass asphalt (LMP), respectively. The pyrolysis process of SMP and LMP conforms to the same dynamic model. The apparent activation energy of SMP is 48.62 kJ/mol and that of LMP is 128.46 kJ/mol. The mass and heating rate of pitch have obvious influences on the LMP pyrolysis process. The apparent activation energy of pyrolysis gradually increases with increasing contents of Na, Ca, and Mg. Moreover, the coke yield and the residual rate of the carbon anode in CO(2) or air increase first and then decrease.