In the complex world of water treatment, the performance of coagulants like Poly Aluminium Chloride (PAC) is influenced by several factors, with basicity being one of the most critical. For procurement managers and R&D scientists seeking to maximize the efficiency of their water treatment processes, understanding PAC basicity is essential for making informed purchasing decisions. As a dedicated manufacturer and supplier of PAC, we aim to clarify this vital parameter.

What is PAC Basicity?

Basicity in Poly Aluminium Chloride refers to the molar ratio of hydroxyl groups (OH-) to aluminum ions (Al3+) within the polymer structure. It is typically expressed as a percentage. This ratio dictates the degree of polymerization and the charge density of the PAC. Different basicity levels lead to PACs with varying chemical properties and, consequently, different performance characteristics in water treatment.

  • Lower Basicity PAC (e.g., 10-40%): These products generally have a lower degree of polymerization and a higher concentration of aluminum ions. They tend to be more acidic and are often effective in removing turbidity and suspended solids, particularly in neutral to alkaline water conditions.
  • Medium Basicity PAC (e.g., 40-65%): This range offers a balance between polymerization and charge density. Medium basicity PACs are versatile and perform well across a broad spectrum of water conditions, effectively tackling turbidity, organic matter, and color.
  • Higher Basicity PAC (e.g., 65-85%): These PACs have a higher degree of polymerization and a greater proportion of hydroxyl groups. They are less acidic, have a lower residual aluminum impact on pH, and are often favored for applications requiring efficient removal of dissolved organic matter and superior performance in colder water or at lower dosages.

How Basicity Influences Performance

The basicity of PAC directly impacts its coagulant properties:

  • Floc Formation: Higher basicity generally leads to the formation of larger, more stable flocs, improving sedimentation and filtration efficiency.
  • Charge Neutralization: The positively charged aluminum species in PAC neutralize negatively charged colloidal particles in water, initiating the coagulation process. The effectiveness of this neutralization is influenced by basicity.
  • pH Adjustment: PACs with higher basicity are less acidic and thus have a smaller impact on the pH of the treated water, potentially reducing the need for additional pH adjustment chemicals.
  • Residual Aluminum: Higher basicity products often result in lower residual aluminum concentrations in the treated water, which is a key consideration for drinking water safety.

Selecting the Right PAC for Your Application

Choosing the appropriate PAC based on its basicity requires understanding your specific water treatment objectives:

  • For general turbidity removal in neutral to alkaline water, lower to medium basicity PAC might be suitable.
  • For challenging conditions like low temperatures, low turbidity, or when minimizing pH impact and residual aluminum is crucial, higher basicity PAC is often preferred.
  • For drinking water purification, specialized high-purity PAC with controlled basicity is essential.

When you decide to buy Poly Aluminium Chloride, consult your supplier to determine the optimal basicity for your application. As a leading manufacturer and supplier in China, we offer a range of PAC products with varying basicity levels, backed by technical expertise to guide your selection. We provide competitive pricing and consistent quality, ensuring you get the best value for your investment.

Understanding PAC basicity empowers you to make more informed decisions, leading to more effective and cost-efficient water treatment. We invite you to leverage our expertise when selecting PAC for your industrial, municipal, or drinking water needs.