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 the molecular formula of poly-aluminum chloride?

One of the major pre-polymerized coagulants, poly-aluminum chloride (PACl) is used broadly for water and wastewater treatment. PACl contains different amounts of hydroxyl, and the molecular formula of PACl is [Al m (OH) n (H 2 O) x]·Cl 3m−n (n ≤ 3 m).

What is high-purity poly-aluminum chloride (PACL)?

Poly-aluminum chloride (PACl) is one of the common coagulants for water and wastewater treatment. A new Chinese national standard of PACl has been implemented, where the concentration of insoluble substances, iron and heavy metals is to be controlled strictly, then researches on the preparation of high-purity PACl are needed.

What is the performance of synthesized PAC compared with aluminum sulfate?

The performance of synthesized PAC compared with aluminum sulfate, aluminum chloride and commercial PAC for water treatment. 4. Conclusion The synthesis of PΑC results revealed that the low concentration of aluminum chloride favored to the formation of Αl b species of PΑC and the high concentration preferred to the formation of Αl c species of PΑC.

What are the synthesis parameters of aluminum chloride hexahydrate?

The synthesis parameters were concentration of aluminum chloride hexahydrate (0.4 to 0.8 M), basicity ratio (2.0 to 2.4), reaction temperature (60 to 80 °C) and time (180 to 360 min). The performance of PΑC for water treatment was also investigated. The monomeric, medium polymeric and colloidal species of PAC were determined by Ferron test method.

How is polyaluminium chloride synthesized?

Synthesis of polyaluminium chloride 2.1.1. Preparation of solutions (min 37%). Granular Al was introduced slowly and in small portions to continuous magnetic stirring. After the introduction of the fi rst heating was not needed. without heating. A portion of NaOH solution (10 –50%) was placed in a 500 mL flask on a magnetic stirrer.