Flocculated Suspension vs. Deflocculated Suspension — What's the Difference?

A Flocculated Suspension refers to a state where the particles within a suspension aggregate, forming loose clusters or clumps known as flocs. These flocs come together due to weak van der Waals forces, leading to the creation of larger entities that settle rapidly. On the contrary, a Deflocculated Suspension is characterized by particles that remain individually dispersed and resist forming aggregates. This is due to the repulsive forces between the particles, ensuring they remain separate.

Flocculated Suspensions typically exhibit a clear liquid supernatant above the settled particles, as the formation of flocs causes rapid settling. This is in stark contrast to Deflocculated Suspensions, where the particles are uniformly distributed, leading to an even appearance without a clear supernatant layer.

The behavior of a Flocculated Suspension under sedimentation is distinctive; they exhibit a higher rate of sedimentation but form a porous sediment. Deflocculated Suspensions, meanwhile, settle slowly and produce a compact, hard sediment due to the closeness of the particles.

In terms of redispersibility, a Flocculated Suspension can be easily redispersed upon shaking. This is because the forces holding the particles together in flocs are weak. However, a Deflocculated Suspension, once settled, is difficult to redisperse due to the strong repulsive forces that originally kept the particles apart.

When it comes to stability, Flocculated Suspensions are generally considered less stable as they can lead to larger aggregates or even cause caking upon prolonged standing. Deflocculated Suspensions are more stable in this aspect, as the particles tend to resist aggregation.