Continuous Operation on Synthesis and Surface Modification of Rutile Nanoparticles in Designed Microfluidic Reactors

Synthesis and surface modification of rutile nanoparticles (NPs) are two distinct processes. Conventionally, they should be conducted separately. In this work, synthesis and surface modification of rutile NPs are consecutively performed in a designed microfluidic system, thereby avoiding the pilot processes, giving a high controllability and low-energy consumption of the process, and the preparation process of the coated TiO₂ is simplified effectively. Samples synthesized using different strategies are compared, and the results demonstrate that the sample prepared using the microfluidic method shows a smaller particle size (60 nm) and a narrower particle size distribution range than those synthesized using the other two methods. Rutile NPs are most commonly used in terms of suspensions, the stability of the suspensions consisting of the naked and coated samples are assessed in terms of turbidity, agglomeration size, and settlement rate. Response surface methodology is employed to quantify the effects of the factors on the stability of suspensions.