In situ observation of colloidal particle behavior between two planar surfaces

• A in situ fluorescence observation system was developed.
• Colloidal particles motion between two planar surfaces was observed.
• The velocity of colloidal particles in alkaline slurry is anomalously high.
• A model describing the particle motion was built to explain the phenomenon.

The interaction forces acting between colloidal particles and planar plates in liquids play an important role in determining the behaviors of the particles. An anomalously high speed motion of colloidal particles was observed in the present work on the basis of a self-developed fluorescence device. The particle speed is about an order of magnitude higher than the rotation speed of the plate. The particles in alkaline solutions move much faster than those in acidic solutions when the plate rotation speed is identical. Such differences have been explained with a physical model describing the significant contribution to particle motion from the interfacial forces between particles and solid surfaces.

Figure optionsDownload as PowerPoint slide