Polyaluminium Chloride (PAC) for Water Treatment

What Is Polyaluminium Chloride (PAC)?

Polyaluminium Chloride, also written as Polyaluminum Chloride or Poly Aluminum Chloride, is a pre-polymerized inorganic aluminum salt used primarily as a coagulant in water and wastewater treatment.

PAC is not a single pure molecule with one fixed molecular weight. It is a family of partially hydrolyzed aluminum chloride products commonly represented by the general formula [Al₂(OH)nCl₆−n]m.

Compared with conventional aluminum salts, PAC contains preformed aluminum hydroxy complexes that can destabilize suspended particles and support rapid floc formation under suitable treatment conditions.

Polyaluminium Chloride Product Information

PAC is an inorganic water-treatment chemical. It is generally classified as a basic or specialty inorganic coagulant rather than a chemical intermediate.

PAC Powder and Liquid Grades

Powder Polyaluminium Chloride

Powder PAC commonly contains approximately 28–30% Al₂O₃, depending on the manufacturing process and product grade. It is suitable for customers who require more economical international transportation, longer storage or on-site solution preparation.

The dissolution rate, water-insoluble matter, dust level and solution clarity should be evaluated before selecting a powder grade.

Liquid Polyaluminium Chloride

Liquid PAC is supplied as a ready-to-meter solution and does not require powder dissolution equipment. Commercial liquid grades commonly contain approximately 10–18% Al₂O₃.

Buyers should compare Al₂O₃ concentration, basicity, density, sediment content and storage stability. Transportation cost may be higher because the product contains more water.

Potable-Water and Industrial Grades

Product color alone does not determine whether PAC is suitable for drinking-water treatment. White or pale-yellow PAC should not automatically be described as potable-water grade.

For drinking-water applications, confirm compliance with the applicable national or regional standard, including limits for arsenic, lead, cadmium, mercury and other regulated impurities.

Which PAC Specifications Should Buyers Compare?

A higher basicity or Al₂O₃ value is not automatically better for every water source. The correct grade depends on turbidity, alkalinity, pH, temperature, natural organic matter and the existing treatment process.

How Does Polyaluminium Chloride Work?

After PAC is added to water, its positively charged aluminum hydroxy species interact with negatively charged colloids and suspended particles.

Rapid mixing disperses the coagulant, while controlled slow mixing allows destabilized particles to collide and form larger flocs. The resulting flocs are then removed by sedimentation, flotation or filtration.

Where Is PAC Used?

Polyaluminium Chloride is commonly used in:

• Drinking-water clarification, using a compliant and approved grade

• Municipal wastewater treatment

• Industrial wastewater clarification

• Raw-water and process-water treatment

• Suspended-solids and turbidity removal

• Paper manufacturing and process-water treatment

• Pretreatment before filtration or membrane systems

Color, phosphorus and organic-matter removal performance depends on water chemistry and operating conditions. Application performance should therefore be confirmed through laboratory or plant testing.

PAC vs Aluminum Sulfate

PAC may improve clarification or reduce alkali demand in some treatment systems, but it should not be presented as universally superior. Comparative jar testing provides the most reliable basis for replacement decisions.

How Should a PAC Grade Be Selected?

Before ordering, provide the supplier with:

1. The intended application

2. Required powder or liquid form

3. Target Al₂O₃ content

4. Required basicity range

5. Limits for insoluble matter, iron and trace metals

6. Applicable drinking-water or industrial standard

7. Packaging and annual consumption

8. Destination port or delivery location

A jar test should be performed before full-scale use. The optimum dosage depends on raw-water quality, pH, alkalinity, temperature, mixing energy and treatment objectives.

Packaging, Storage and Safe Handling

Powder PAC is commonly supplied in moisture-resistant bags, while liquid PAC may be delivered in drums, IBCs or bulk tankers. Final packaging should be confirmed according to grade, quantity and destination.

Store powder PAC in a cool, dry and ventilated area with the packaging tightly closed. Store liquid PAC in compatible, corrosion-resistant tanks and prevent contamination or unintended dilution.

Avoid breathing powder dust and prevent contact with the eyes and skin. Wear suitable gloves, protective clothing and eye protection. Always consult the current Safety Data Sheet before handling.

Why Source Polyaluminium Chloride from AOZUN?

AOZUN supports international buyers with grade selection based on application and specification requirements.

Available support can include:

• Powder and liquid PAC sourcing

• Specification and sample evaluation

• COA, SDS and technical documentation

• Packaging and export-logistics coordination

• Pre-shipment quality verification

• Grade comparison for industrial and water-treatment applications

Certification, impurity limits and compliance documents should be confirmed for each individual grade before purchase.

Polyaluminium Chloride FAQ

Is PAC organic or inorganic?

PAC is inorganic. It is a pre-polymerized aluminum salt and an inorganic coagulant used mainly in water treatment.

Is PAC a coagulant or a flocculant?

PAC is primarily a coagulant. It destabilizes suspended particles so they can form flocs. An organic flocculant such as polyacrylamide may be added separately when supported by jar-test results.

Is white PAC always drinking-water grade?

No. Color is not proof of regulatory compliance. Buyers must check the applicable standard, trace-metal limits, certification and maximum permitted use level.

Is higher PAC basicity always better?

No. The most suitable basicity depends on the water source, pH, alkalinity, treatment process and performance target.

Can PAC replace aluminum sulfate directly?

PAC can replace aluminum sulfate in many systems, but the products should not be exchanged solely by weight. Comparative jar testing and dosage optimization are required.

Request a PAC Specification and Quotation

Contact AOZUN with your required PAC form, Al₂O₃ content, basicity, application, quality standard, packaging, order quantity and destination.

We can help evaluate a suitable Polyaluminium Chloride grade and prepare a quotation based on your technical and delivery requirements.