Why is polyaluminum chloride a good coagulant for water treatment?

Polyaluminum chloride (PAC) is highly effective coagulant for water treatment over conventional coagulants because of low dosage requirement, shorter flocculation time, smaller amount of sludge, high efficiency and low aluminum residual in treated water .

What is polyaluminum chloride (PAC)?

Polyaluminum chloride (PAC) is a classic inorganic polymer material, which has the advantages of easy preparation, low cost, and high efficiency in the field of water treatment and other areas of environmental protection [1, 2].

Does polyaluminum chloride coagulate with hydrolyzed coagulants?

Coagulation with hydrolyzing coagulants has been studied thoroughly, but the coagulation behavior of pre-hydrolyzed coagulants such as polyaluminum chloride (PACl), especially the coagulation mechanisms at various coagulant dosages and pH values of raw water, has not been systemically investigated and not been well understood , .

How much product can be obtained from a polymer flocculant?

When the reaction scale was expanded to 20 mmol, 6.23 g (89%) of product could be obtained. The classic inorganic polymer flocculant—polyaluminum chloride (PAC)—was used as an environmentally friendly, efficient, and recyclable catalyst in the synthesis of Bis (indolyl)methanes (BIMs) compounds for the first time.

What is polyaluminum chloride used for?

The classic inorganic polymer flocculant—polyaluminum chloride (PAC)—was used as an environmentally friendly, efficient, and recyclable catalyst in the synthesis of Bis (indolyl)methanes (BIMs) compounds for the first time. The strategy of catalysis is to use PAC as a Lewis acid, which contains different structures of Al–O polynuclear cations.

Is PAC a polymer flocculation catalyst?

The literature also indicates that Al 13 has a molecular scale of 1–2 nm and has a high charge, which is considered to be the most stable active species in PAC. Thus, PAC as “inorganic polymer flocculation catalyst” demonstrated its structural characteristics in the organic synthesis reaction system.