1. Functional Groups:
- Acidic Pellets: Acidic pellets contain sulfonic acid functional groups (-SO3H). These groups can release hydrogen ions (H+) when in contact with water, making the water acidic.
- Basic Pellets: Basic pellets contain quaternary ammonium functional groups (-NR3+). These groups can attract and exchange positively charged ions, making the water alkaline.
2. Ion Exchange Capacity:
- Acidic Pellets: Acidic pellets have a high affinity for positively charged ions (cations), such as calcium, magnesium, and sodium. They remove these cations from the water and replace them with hydrogen ions.
- Basic Pellets: Basic pellets have a high affinity for negatively charged ions (anions), such as chloride, sulfate, and nitrate. They remove these anions from the water and replace them with hydroxide ions (OH-).
3. pH Effect:
- Acidic Pellets: As acidic pellets release hydrogen ions, they lower the pH of the water, making it more acidic.
- Basic Pellets: As basic pellets release hydroxide ions, they increase the pH of the water, making it more alkaline.
4. Applications:
- Acidic Pellets: Acidic pellets are commonly used in water softening applications. They remove hardness-causing ions such as calcium and magnesium, replacing them with hydrogen ions. This process results in softened water.
- Basic Pellets: Basic pellets are often used in deionization applications. They remove a wide range of anions and cations from the water, producing deionized or purified water.
5. Regeneration:
- Acidic Pellets: Acidic pellets are regenerated using an acid solution, typically hydrochloric acid (HCl).
- Basic Pellets: Basic pellets are regenerated using a caustic solution, such as sodium hydroxide (NaOH).
Both acidic and basic pellets play essential roles in water treatment, depending on the desired water quality and specific application requirements.
