ATBS·Na (also called AMPS·Na, CAS No. 5165-97-9) is a sulfonate-containing anionic monomer widely used in water treatment, oilfields, and polymer industries. Its key function is derived from its strong hydrophilic sulfonic acid group (-SO₃⁻), which provides exceptional dispersion, scale inhibition, and high-temperature resistance.
1. Core Functions
(1) Scale Inhibition & Dispersion
- Target Scales:
- Inhibits CaCO₃, CaSO₄, BaSO₄, and silica scales in high-hardness water.
- Disperses Fe₂O₃, clay, and colloidal particles to prevent fouling.
- Mechanism:
- The sulfonate group (-SO₃⁻) provides strong electrostatic repulsion, preventing crystal growth and particle agglomeration.
- Works synergistically with phosphonates (HEDP) or polycarboxylates (PAA).
(2) Thermal and Chemical Stability
- High-Temperature Resistance: Stable up to 200°C (compared to acrylic acid polymers, which degrade at ~120°C).
- Oxidant Resistance: Resists chlorine (Cl₂), hydrogen peroxide (H₂O₂), and other oxidizers.
(3) Enhanced Polymer Performance
- Used as a co-monomer to synthesize high-performance copolymers (e.g., AA/AMPS, used in RO antiscalants).
- Improves hydrolytic stability of polymers in saline or high-pH environments.
2. Key Applications
| Industry | Role | Dosage |
|---|---|---|
| Cooling Water | Prevents CaCO₃/Ca₃(PO₄)₂ scaling in heat exchangers. | 5–20 mg/L |
| Oilfield | Controls BaSO₄/SrSO₄ scaling in produced water. | 10–50 mg/L |
| RO/Desalination | Inhibits silica and sulfate scaling on membranes. | 2–10 mg/L |
| Textile Dyeing | Disperses dyes and prevents metal ion interference (Fe³⁺, Ca²⁺). | 0.1–0.5% |
| Enhanced Oil Recovery (EOR) | Improves polymer (HPAM) stability in high-salinity reservoirs. | 0.05–0.2% |
3. Advantages Over Conventional Monomers
| Property | ATBS·Na | Acrylic Acid (AA) |
|---|---|---|
| Thermal Stability | Up to 200°C | Degrades at ~120°C |
| Oxidation Resistance | Excellent | Poor (breaks down with Cl₂) |
| Salt Tolerance | High (works in seawater) | Low (precipitates in high Ca²⁺) |
| Dispersion Power | ★★★★★ (strong -SO₃⁻) | ★★☆☆☆ (only -COOH) |
4. Technical Specifications (Example)
| Parameter | Specification |
|---|---|
| Appearance | White crystalline powder |
| Purity | ≥98% |
| Solubility | Highly water-soluble |
| pH (1% solution) | 6.0–8.0 |
5. Safety & Handling
- Toxicity: Low (LD₅₀ > 2000 mg/kg, non-irritating to skin).
- Storage: Keep dry (hygroscopic) and away from strong oxidizers.
Conclusion
ATBS·Na is a versatile, high-performance monomer that enhances scale inhibition, dispersion, and thermal stability in water treatment and oilfield applications. Its sulfonic acid group makes it superior to traditional acrylic acid-based polymers, especially in high-temperature, high-salinity, or oxidizing environments.
Typical Use Case:
- In RO antiscalants, it prevents silica scaling where conventional polymers fail.
- In oilfield scale inhibitors, it improves BaSO₄ inhibition in brine water.
For optimal performance, it is often copolymerized with acrylic acid (AA) or maleic anhydride (MA).