In this study, a heterogeneous structure-based mass-transfer model is established coupled with the mass-transfer equilibrium between internal/external diffusions and the chemical reaction, which is adopted to simulate the fluidized reaction with a shrinking core model by using the computational fluid dynamics. This research opens new process-specific insights into the fluid-solid reaction, such as the effects of different reaction parameters on the solid conversion rate, the variations of reaction rates for solid and gas phases, unreacted core size and particle density, gaseous reactant concentration at the unreacted core surface, and concentration gradient at the particle shell. It is proved that a reasonable numerical investigation of gas-solid mass-transfer behavior should take account of fluid dynamics, reaction kinetics, and heterogeneous flow structure, comprehensively.