PAC vs PAFC: pH Performance Comparison & Best Practices for Water Treatment

1. Key Differences Between PAC and PAFC

• PAC (Polyaluminum Chloride): Dominated by aluminum hydrolysis, best for neutral to slightly alkaline water.

• PAFC (Polyaluminum Ferric Chloride): Contains Fe³⁺, offering better charge neutralization and faster settling, ideal for acidic or high-turbidity water.

2. pH Impact on Performance

(1) Acidic Conditions (pH < 6)

• PAC: Poor hydrolysis, requires 30%~50% higher dosage.

• PAFC: Fe³⁺ remains stable, achieving 85% turbidity removal at pH=4.

(2) Neutral Conditions (pH 6~8)

• PAC: Optimal for municipal wastewater (90%+ COD removal).

• PAFC: 20%~30% faster settling, good for phosphorus removal.

(3) Alkaline Conditions (pH > 8)

• PAC: Over-hydrolysis leads to weak flocs.

• PAFC: More stable, suitable for textile/paper wastewater.

3. Experimental Data

4. Industrial Recommendations

• Acidic Wastewater → PAFC (e.g., electroplating, mining)

• Neutral Wastewater → PAC (e.g., municipal sewage)

• Alkaline Wastewater → PAFC + PAM (e.g., paper mills)