Oxidation of THEAQH(2) is an important step in H2O2 synthesis via ethylanthraquinone method. For realizing the process with more safety, a microstructured system is developed and fast oxidation reaction is realized in the system. The system contains a gas-liquid microdispersion device with a 5 mu m pore size microfiltration membrane as the dispersion medium for forming microbubbles and a capillary for controlling the residence time. The microdisperion device can control the microbubbles in the range of 10-200 mu m. Both oxidation with O-2 and air have been studied, respectively. Conversion over 99.5% is realized in 15s as O-2 is used, which is much shorter than tens of minutes in conventional industry. Mathematical models have been set up to correlate the reaction process, for oxidation with O-2 and air, respectively, giving satisfactory results over the operation conditions in our experiments. The intrinsic reaction kinetics constant is measured and the activation energy is determined as well using the new system. (C) 2011 Elsevier B.V. All rights reserved.