Research on ContinuousSynthesis of NanoparticlesUsing an Inline High-Shear Mixer: Barium Sulfate

Nanoparticle preparation is the foundation of nanotechnology. Owing to its excellent micromixing and disaggregation performance, the high shear mixer (HSM) is a promising tool for nanoparticle preparation. However, limited research has hindered its understanding and application. Therefore, this work systematically investigates for the first time the effects of rotor tip velocity <i>u</i>_i, supersaturation, feed flow rate <i>Q</i>_A, free ion ratio <i>R</i>_f, and rotor–stator configuration on the precipitation of barium sulfate using inline HSM. The results indicate that the nucleation mechanism, micromixing, and shear collectively determine the primary particle mean size <i>d</i>_m and agglomerate mean size <i>d</i>₄₃ of barium sulfate precipitation. Higher <i>R</i>_f, more rotor–stator slotting, or an appropriate increase in <i>u</i>_i can effectively reduce <i>d</i>_m and <i>d</i>₄₃. Finally, the correlation equation for <i>d</i>₄₃ is provided. These results offer valuable insights for the design and application of inline HSM in nanoparticle preparation.