Abstract:

A T-type microchannel reactor was used to prepare Mg-Al layered double hydroxides(LDHs) via the coprecipitation method. The effects of flow rate of reactant solutions, concentration of mixed salt solution and temperature on the particle size and the particle size distribution of the LDH samples were examined. The results show that the morphology and crystal structure of the LDH samples obtained using the T-type microchannel reactor are similar to those of the materials synthesized by the conventional coprecipitation method. However, the T-type microchannel reactor route could afford smaller particle size and very narrow distribution of particle size for the materials. The flow rate, concentration of mixed salt solution and temperature have an important influence on the particle size and the particle size distribution of the obtained LDH samples. With the increases of the flow rate and temperature, the particle size and the particle size distribution of the obtained LDH samples decreased, while with the increase of the concentration of mixed salt solution, those increased. A major advantage of the T-type microchannel reactor route is that the particle size and the particle size distribution of the as-obtained samples can be simply and effectively controlled by the flow rates of the reactant solutions.

Key words: Microchannel reactor, Coprecipitation method, Layered double hydroxide(LDH), Particle size distribution