The process by which metal hydroxides capture colloids is known as what?

The process by which metal hydroxides capture colloids is known as sweep floc. This mechanism involves the aggregation of particles when metal hydroxides form in the presence of colloidal suspensions. As the metal hydroxides precipitate, they essentially "sweep" through the water, colliding with colloidal particles, adhering to them, and facilitating their aggregation into larger flocs. This process enhances the removal of these particles during subsequent treatment steps, such as sedimentation or filtration.

In contrast, charge neutralization refers to the neutralizing effect that occurs when oppositely charged particles attract each other, which can be an important aspect in coagulation but does not specifically involve the sweeping mechanism. Negative and positive coagulation describe different interactions based on the charge of the particles involved, rather than focusing on the sweeping action of floc formation by metal hydroxides. Sweep floc is particularly effective in enhancing the efficiency of the treatment process by effectively consolidating dispersed colloidal matter.