T形微反应器共沉淀法制备Mg-Al层状双金属氢氧化物及其粒径可控性

Preparation and Particle Size Controllability of Mg-Al Layered Double Hydroxides via Coprecipitation Method Using T-type Microchannel Reactor

采用T形微反应器通过共沉淀法制备了Mg-Al层状双金属氢氧化物(LDHs)纳米颗粒,考察了流速、混合盐溶液浓度和温度等对产物粒径及其分布的影响.实验结果表明,所制备的LDHs样品的形貌和晶体结构与传统共沉淀法结果一致,但本方法制备的样品粒径小、分布窄.随着流速增大,温度升高,所合成的LDHs样品平均粒径减小,分布变窄;而随着混合盐溶液浓度的增大,所得LDHs样品粒径增大,分布变宽.

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.