Poly Aluminium Chloride — PAC — is one of the most widely used coagulants in modern water and effluent treatment. It has largely replaced older alum-based coagulants in many plants because it works across a wider pH range, produces stronger flocs, and leaves less residual sludge.
Supreme Petro Chemicals supplies PAC from Chennai to municipal water works, effluent treatment plants (ETPs), paper mills, and process industries across South India, in both liquid and powder grades.
What Is Poly Aluminium Chloride?
PAC has CAS number 1327-41-9. It is an inorganic polymer of aluminium chloride, described by its aluminium oxide (Al2O3) content and its basicity. It is supplied as a pale yellow liquid or as a yellow spray-dried powder. The polymeric, pre-hydrolysed structure is what gives PAC its advantage over simple aluminium salts — the coagulation chemistry is already partly complete before it reaches the water.
How PAC Works as a Coagulant
Raw water and effluent carry fine suspended particles that stay dispersed because they hold like electrical charges and repel one another. PAC neutralises those charges and bridges the particles together, so they clump into larger "flocs" that settle out or can be filtered. The result is clarified water with lower turbidity, colour, and suspended solids.
Compared with alum, PAC typically needs a lower dose, works over a broader pH band, consumes less alkalinity, and performs better in cold water — which is why many plants have switched to it.
Liquid vs Powder Grades
- Liquid PAC is ready to dose and convenient for plants with continuous dosing systems and steady consumption. It is typically supplied at around 10% Al2O3.
- Powder (spray-dried) PAC has a higher Al2O3 content (commonly in the high-twenties to ~30%), is lighter to transport per unit of active content, and stores longer. It is made down to solution before dosing.
The right choice depends on your dosing equipment, storage, transport distance, and how quickly you use stock. Share these details when you enquire and we will recommend the grade that fits.
Where PAC Is Used
- Municipal drinking water: Clarification and turbidity removal in potable water treatment.
- Effluent treatment (ETP/STP): Removing suspended solids, colour, and phosphates from industrial and sewage effluent.
- Paper manufacturing: As a retention and sizing aid.
- Process and cooling water: Pre-treatment clarification.
PAC is often used alongside other treatment chemicals such as bleaching powder for disinfection and TCCA for chlorination, depending on the plant.
Handling and Storage
PAC is acidic in solution and mildly corrosive. Store it in compatible (plastic or lined) containers, away from strong alkalis, in a cool, dry area — and keep powder grades sealed against moisture. Use appropriate gloves and eye protection when handling and dosing, and follow the product SDS.
Packaging and Supply
Powder PAC is supplied in 25 kg bags; liquid PAC is supplied in carboys, drums, and bulk depending on volume. Minimum order and dispatch depend on grade, quantity, and delivery location. For continuous plant operation, share your monthly consumption so stock can be planned in advance.
FAQ
What is the CAS number of Poly Aluminium Chloride?
Poly Aluminium Chloride (PAC) has CAS number 1327-41-9. It is graded by its aluminium oxide (Al2O3) content and basicity rather than a single fixed purity, so specify the grade you need when ordering.
Is PAC better than alum for water treatment?
For most plants, yes. PAC generally needs a lower dose, works across a wider pH range, consumes less alkalinity, forms stronger flocs, and produces less sludge than alum. It also performs better in cold water. The best choice still depends on your raw water and plant setup.
Does SPC supply both liquid and powder PAC?
Yes. Supreme Petro Chemicals supplies both liquid PAC and spray-dried powder PAC from Chennai. Share your dosing system, consumption, and delivery location and we will recommend the grade and packaging that suit your plant.
Get a PAC Quote from SPC
For Poly Aluminium Chloride supply from Chennai, view PAC in our catalogue, call +91 86087 80096, WhatsApp an enquiry, or use the SPC enquiry form.