Poly Aluminium Chloride (PAC) is one of the most widely used inorganic coagulants in water and wastewater treatment. It is used to remove suspended solids, colloids, turbidity, and other impurities through coagulation and floc formation. PAC is used in drinking water treatment, municipal wastewater treatment, and many industrial applications.
For buyers, however, choosing PAC is not always as simple as comparing prices. One common question is: What is the difference between White PAC and Yellow PAC, and which one should you choose?
The short answer is that White PAC is generally preferred for applications with higher purity requirements, while Yellow PAC is commonly selected for general municipal and industrial wastewater treatment where cost efficiency and broad applicability are important.
However, color alone does not determine PAC quality. Buyers should also compare product specifications, water quality, treatment objectives, and applicable requirements before making a decision.
This guide explains the key differences between White PAC and Yellow PAC and provides a practical selection guide for water treatment chemical buyers.
What Is the Difference Between White PAC and Yellow PAC?
White PAC and Yellow PAC are both forms of Poly Aluminium Chloride. Their main differences relate to raw material purity, impurity control, product specifications, production requirements, and typical applications.
HOO CHEMTEC currently supplies both White PAC and Yellow PAC. Its product specifications include parameters such as Al₂O₃ content, basicity, water-insoluble matter, pH, arsenic, lead, cadmium, and iron, depending on the grade.
Before comparing the two products, it is useful to understand what each type is designed for.
What Is White Poly Aluminium Chloride?
White Poly Aluminium Chloride is a high-purity PAC powder. It is typically produced from higher-purity raw materials and is designed for applications where control of impurities is particularly important.
The product is positioned for high-standard water treatment applications such as drinking water purification, electronics wastewater treatment, and food processing wastewater.
Typical characteristics of White PAC include:
- White or off-white powder appearance
- Higher purity requirements
- Stricter impurity control
- Suitable for purity-sensitive applications
- Relatively higher product cost
For buyers, the important point is that White PAC is not simply a lighter-colored version of Yellow PAC. The product grade and specification should be evaluated based on the actual application.
What Is Yellow Poly Aluminium Chloride?
Yellow Poly Aluminium Chloride is widely used as a general-purpose PAC for water and wastewater treatment. It is commonly selected for applications where coagulation performance, broad applicability, and treatment cost are the main considerations.
HOO CHEMTEC positions Yellow PAC for general wastewater treatment, including municipal sewage, textile dyeing wastewater, and papermaking wastewater. Its current product range includes Yellow PAC grades with Al₂O₃ contents such as 29% and 30%.
Typical characteristics of Yellow PAC include:
- Yellow or light-yellow powder appearance
- Broad application range
- Good balance between performance and cost
- Fast dissolution for water treatment use
- Common use in municipal and industrial wastewater treatment
This makes Yellow PAC a practical option for many large-volume wastewater treatment systems.
White PAC vs. Yellow PAC: Key Differences
The following table provides a quick comparison.
| Factor | White PAC | Yellow PAC |
| Appearance | White or off-white powder | Yellow or light-yellow powder |
| Purity | Higher-purity grade | Standard industrial grade |
| Impurity control | Stricter | Standard control |
| Typical applications | Purity-sensitive water treatment | General water and wastewater treatment |
| Common users | Drinking water and high-standard applications | Municipal and industrial wastewater plants |
| Cost | Usually higher | Generally more cost-effective |
| Main selection factor | Purity and impurity control | Treatment performance and overall cost |
The table provides a useful starting point, but buyers should look beyond appearance and price. The actual PAC specification is much more important when comparing products from different suppliers.
Purity and Impurity Control
One of the main reasons buyers select White PAC is the need for tighter control of impurities.
When comparing PAC products, buyers should review relevant parameters such as:
- Al₂O₃ content
- Basicity
- Water-insoluble matter
- Iron content
- pH
- Heavy metals
- Other application-specific impurities
For example, HOO CHEMTEC’s PAC specifications include Al₂O₃, basicity, water-insoluble matter, pH, arsenic, lead, cadmium, and iron for relevant grades.
Therefore, PAC color should never be the only quality indicator. Two products with different colors may both be suitable for water treatment, while two products with similar colors may have different specifications.
Appearance and Color
Why is White PAC white while Yellow PAC is yellow?
The difference is related to the raw materials, production process, and impurity profile of the product. Iron and other trace components can influence PAC color. HOO CHEMTEC’s existing technical content also notes that PAC can appear in different colors depending on its composition and grade.
However, buyers should avoid a simple assumption such as:
White PAC = good quality
Yellow PAC = low quality
That is not a reliable way to evaluate PAC.
A better approach is:
Color → Product grade → COA → Application requirements → Performance test
This approach gives buyers a more accurate basis for supplier comparison.
Which PAC Should You Choose for Different Water Treatment Applications?
The right PAC depends on the application. Poly Aluminium Chloride is widely used in primary coagulation for drinking water and municipal wastewater treatment, as well as in industrial wastewater applications.
Drinking Water Treatment
For drinking water treatment, buyers generally place greater emphasis on product purity and impurity control.
White PAC may therefore be a suitable starting point when the treatment process requires a high-purity coagulant. However, the final product selection should always match the applicable drinking water regulations, treatment process, and raw water characteristics.
Important factors include:
- Product purity
- Aluminum content
- Iron and other impurities
- Water-insoluble matter
- Basicity
- Raw water turbidity
- Coagulation pH
- Applicable drinking water requirements
It is important to remember that there is no single PAC grade that is automatically the best for every drinking water plant. Coagulant selection should consider raw water quality and the treatment process.
Municipal Wastewater Treatment
Municipal wastewater treatment often involves large water volumes and changing water quality. PAC is commonly used as a primary coagulant to improve the removal of suspended solids and other particulate contaminants.
For general municipal sewage treatment, Yellow PAC is often a practical option because it provides a balance between treatment performance and cost.
Key considerations include:
- Suspended solids
- Turbidity
- Organic matter
- pH
- PAC dosage
- Sludge production
- Overall treatment cost
For large treatment plants, even a small difference in PAC dosage or unit cost can affect annual operating expenses. This is why buyers should evaluate total treatment cost, rather than only the price per metric ton.
Industrial Wastewater Treatment
Industrial wastewater can vary significantly from one industry to another. Textile, papermaking, food processing, electronics, chemical, and other industrial wastewater streams may have very different contaminants.
Yellow PAC is commonly suitable for many general industrial wastewater applications. However, White PAC or another higher-purity grade may be more appropriate when impurity control is a major concern.
For example, HOO CHEMTEC lists Yellow PAC for textile dyeing and papermaking wastewater, while White PAC is positioned for electronics and food processing wastewater applications.
For complex wastewater, buyers should not select PAC based only on industry name. A jar test using the actual wastewater is a more reliable way to determine the suitable grade and dosage.
How Should Buyers Compare White PAC and Yellow PAC?
For B2B buyers, product selection should follow a clear evaluation process.
Check the PAC Specification
When requesting quotations from PAC suppliers, ask for a complete technical specification rather than only a product name.
At minimum, compare:
| Parameter | Why It Matters |
| Al₂O₃ | Indicates the aluminum oxide content of the product |
| Basicity | Influences PAC chemistry and coagulation behavior |
| Water-insoluble matter | Indicates the level of insoluble material |
| pH | Important for treatment process control |
| Fe | Important for applications with stricter impurity requirements |
| Heavy metals | Important for applications with specific quality requirements |
| Appearance | Useful for basic product identification |
The exact parameters required will depend on the application and applicable standards.
Compare Performance, Not Just Price
The lowest PAC price does not always mean the lowest treatment cost.
A better comparison is:
PAC purchase price → Required dosage → Treatment performance → Sludge generation → Overall operating cost
For example, a lower-cost product may require a higher dosage under the same treatment conditions. In that case, the lower purchase price may not result in a lower total treatment cost.
This is particularly important for large municipal and industrial wastewater treatment systems.
Conduct a Jar Test Before Bulk Purchase
A jar test is one of the most practical ways to compare PAC products before making a bulk purchase.
A typical comparison can include:
- Use the same raw water sample.
- Test the same PAC concentration range.
- Compare different PAC products.
- Observe floc formation.
- Measure turbidity removal.
- Observe settling speed.
- Compare the required dosage.
- Select the product that provides the best overall result.
PAC performance depends on factors such as dosage, water chemistry, and operating conditions. Therefore, a sample test is more reliable than choosing a product only from its specification sheet.
HOO CHEMTEC also recommends application testing and dosage optimization for water treatment chemicals rather than relying on a universal dosage.
White PAC vs. Yellow PAC: Quick Selection Guide
If you need a simple starting point, use the following guide:
| Water Treatment Application | Starting PAC Choice |
| Drinking water purification | White PAC |
| High-purity water treatment | White PAC |
| Electronics wastewater | White PAC |
| Food processing wastewater | White PAC / suitable high-purity grade |
| Municipal sewage | Yellow PAC |
| Textile dyeing wastewater | Yellow PAC |
| Papermaking wastewater | Yellow PAC |
| General industrial wastewater | Yellow PAC |
This table is a starting point, not a replacement for product testing.
If purity and impurity control are the main priorities, White PAC is generally the better starting point. If the system treats general municipal or industrial wastewater and cost efficiency is important, Yellow PAC may be the more practical choice.
The final decision should always consider raw water quality, treatment objectives, product specifications, local requirements, and jar test results.
Conclusion
White PAC and Yellow PAC are both useful Poly Aluminium Chloride products, but they serve different purchasing needs.
White PAC is generally a better starting point for purity-sensitive applications where impurity control is important. Yellow PAC is often a practical choice for general municipal and industrial wastewater treatment where broad applicability and cost efficiency are priorities.
The most important lesson is simple:
Do not choose PAC based on color alone. Choose it based on product specifications, water quality, treatment objectives, and actual treatment performance.
For B2B buyers, the best purchasing process is to compare the technical specifications, request a COA and sample, conduct a jar test with the actual water, and then evaluate both treatment performance and total operating cost.
HOO CHEMTEC supplies both White Poly Aluminium Chloride and Yellow Poly Aluminium Chloride for different water treatment applications. The company provides PAC grades with different specifications and supports buyers in selecting suitable products for drinking water, municipal wastewater, and industrial wastewater treatment.
If you are comparing PAC suppliers or looking for the right White PAC or Yellow PAC for your application, contact HOO CHEMTEC to discuss your required specification, application, and quantity.
FAQ
Is White PAC better than Yellow PAC?
Not necessarily. White PAC is generally designed for applications with higher purity requirements, while Yellow PAC is widely used for general municipal and industrial wastewater treatment. The better product depends on the application and required specifications.
Can Yellow PAC be used for drinking water treatment?
It depends on the specific product grade and applicable requirements. Buyers should check the manufacturer’s specification, impurity profile, certification, and local drinking water requirements before selecting a PAC product for potable water treatment.
Why is White PAC more expensive than Yellow PAC?
White PAC usually requires higher-purity raw materials and tighter impurity control. These additional quality requirements can increase production costs. Therefore, White PAC is generally positioned for applications where purity is more important than the lowest purchase price.
Does PAC color indicate its quality?
No. Color alone does not determine PAC quality. Buyers should compare Al₂O₃, basicity, water-insoluble matter, iron, pH, heavy metals, and other relevant specifications.
Which PAC is better for industrial wastewater?
Yellow PAC is often a practical choice for general industrial wastewater treatment because of its broad application range and cost-effectiveness. However, specific industrial wastewater may require a different PAC grade. A jar test is recommended before large-scale purchasing.
How can I choose a reliable PAC supplier?
Start by comparing the supplier’s product specifications, COA, sample quality, production consistency, packaging, supply capacity, and technical support. A reliable supplier should also be able to recommend a suitable PAC grade based on your application rather than simply offering the lowest price.
