Propagation of a subdiffusion reaction front and the “aging” of particles

The minimum velocity of a subdiffusion reaction front has been determined for two cases distinguishing in details of reaction kinetics. In the first and second cases, a particle that is a product of the chemical reaction acquires the mobility of the first and second reagents, respectively. Although the diffusion properties of both reagents are the same, the front velocity in the first and second cases is nonzero and zero, respectively. The difference is explained by the fact that the propagation of the front leads to the selection of the particles of one of the reagent in mobilities. The average mobility of the particles of this reagent located in the front region is higher than that of the particles beyond the front.