A microreactor competent to control the microprecipitation environment is exploited to investigate the direct precipitation process between iron and phosphorus sources. The dependency of the reaction species on the purity of the final products is revealed. The Fe 3+ hydrolysis and the pH of the mixture are confirmed to have decisive influences on the generation of byproducts. The addition of phosphoric acid in the iron source is verified to be an effective method to simultaneously inhibit Fe 3+ hydrolysis and adjust the pH of the mixture. By optimizing the amount of phosphoric acid addition, pure nanoiron phosphate with an average size of ca. 20 nm is successfully prepared by a continuous precipitation process. Assuming instantaneous mixing and fast precipitation reactions, Fe 3+ and HPO 4 2− are indicated as the main species during the pure iron phosphate precipitation. The criteria would lay a practical guidance for achieving a continuous synthesis of nanoiron phosphate with high purity.

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Ethyl diazoacetate (EDA) commonly experiences intensive decomposition as well as complex conversion concerning safety and efficiency. In this work, a careful kinetics study on the thermal decomposition of EDA was isothermally conducted in a microtube reactor to establish a mechanism-based kinetic model. The model parameters were well calibrated with experimental data including the yield of dimmers and the conversion of EDA, confirming the rationality of the proposed three-step reaction route. It allows the model to concisely describe the complex species transformations during EDA decomposition, which is unavailable for an apparent kinetic model. Considering an isothermal reaction system and the tolerance of EDA consumption by thermal decomposition, this work could help reveal the requirement on the kinetic characteristics of the desired catalytic reaction in which EDA is involved, as a reference on reaction process modeling and regulation.