PAC, AC, and ALU: Differences and Selection Guide for Water Treatment Materials

In the water treatment industry, aluminum-based coagulants are widely used for their excellent flocculation performance, especially Polyaluminum Chloride (PAC), Aluminum Chloride (AlCl₃), and other aluminum salts. However, many users are often confused when choosing among them. This article explores the key differences and helps you select the most suitable water treatment chemical.

1. Product Definition & Chemical Structure

PAC (Polyaluminum Chloride)
A high-polymer inorganic coagulant with a multi-core hydroxyl-complex structure. It hydrolyzes slowly and provides strong flocculation capacity.

Aluminum Chloride (AlCl₃)
A monomer inorganic salt that hydrolyzes quickly. It works in a narrow pH range and generates a strongly acidic environment.

Other Aluminum Salts
Include Aluminum Sulfate, ACH (Polyaluminum Hydroxychloride), BAC (Basic Aluminum Chloride). Their composition and performance vary widely based on usage.

2. Performance Comparison

3. How to Choose the Right Product?

Your selection should be based on water quality and treatment goals:

√ For drinking water or domestic wastewater: PAC is recommended for its low impurity content and excellent performance.

√ For industrial or high-turbidity wastewater: ACH or BAC offer better adaptability.

√ For acidic water environments: Aluminum Chloride (AlCl₃) may be used, but anti-corrosion measures are needed.

√ For budget-conscious applications: PAC is the most cost-effective option.

4. Final Thoughts

Understanding the difference between PAC, AlCl₃, and other aluminum salts ensures more efficient, safer, and cost-effective water treatment.

PAC remains the top choice for general applications, while specialized products can better serve specific needs.