Does polyaluminum chloride hydrolysis affect kaolin coagulation performance?

The effects of polyaluminum chloride (PACl) hydrolysis prior to coagulation on both the coagulation zone and coagulation performance of a kaolin suspension were investigated by a novel jar test named the “reversed coagulation test”.

Does PACL hydrolysis improve charge neutralization coagulation?

The tests showed that PACl hydrolysis prior to coagulation decreased the performance of charge neutralization coagulation in the case of short-time slow mixing (10 min; G = 15 sec − 1) and increased the optimal dosage for charge neutralization and sweep coagulation.

Does hydrolysis time affect kaolin coagulation?

For charge neutralization coagulation, the hydrolysis time of PACl had insignificant effects on the residual turbidity of the kaolin suspension in the case of short-time slow mixing (10 min), and simultaneously on the size and zeta potential of PACl precipitates formed during hydrolysis.

Does pH affect the hydrolysis of PACL?

Based on the work done by Wang et al. (2004), solution pH has a significant effect on the hydrolysis of PACl, especially for PACl with a low basicity ( [OH]/ [Al]). It was found that a large amount of Al b can form for PACl within weak acidic condition, but it transforms quickly into Al c after aging.

Does polymeric aluminum chloride coagulate efficiently?

Taking the more widely used polymeric aluminum chloride (PACl) as an example, coagulation efficiency is closely related to the characteristics and distribution of Al species of PACl (He et al. 2024).

How does aluminum hydrolysis affect kaolin amorphous solids?

The adsorption of these kinds of aluminum hydrolysis products results in destabilization of the kaolin particles—charge neutralization. In most cases, the aluminum hydroxide amorphous solids form so rapidly (1–2s) that they are responsible for the charge neutralization of natural particles .