The direct quadrature method of moments combined with the interaction by exchange with the mean model (named as DQMOM-IEM) is applied to simulate the novel reactive-PLIF (planar laser induced fluorescence) experiment in an unbaffled stirred reactor. By using the mixture fraction and reaction progress variables, the descriptions of the Fenton reaction and oxidation reaction of Rhodamine B are formulated. The quenching of fluorescent signal can be visualized by solving the probability, probability weighted mixture fraction and reaction progress variables used in the two-environment DQMOM coupled with the IEM micro-mixing model. The effect of impeller speed on the mixing and reactions are revealed by the simulated dynamic processes. The predictions by DQMOM-IEM micro-mixing model agree well with the experimental data, suggesting that this model is an effective approach for numerical prediction of turbulent reactive flow in stirred reactors.