1. Core Dissolution Data (25°C, pure water, standard stirring)
| Item | EDTA Disodium (EDTA-2Na) | EDTA Tetrasodium (EDTA-4Na) |
|---|---|---|
| Maximum solubility | ~10 g/L | ~60 g/L |
| Dissolution speed | Slow; requires long stirring | Extremely fast; dissolves almost instantly |
| Dissolution state | Easy to form lumps/undissolved particles | No caking, uniform solution |
| Required stirring time | 10–20 mins for full dissolution | 1–3 mins for full dissolution |
2. Performance on Automated Production Lines
EDTA-2Na
Drawbacks:
Low solubility cannot prepare high-concentration stock solutions, limiting feeding efficiency.
Slow dissolution and caking risk lead to undissolved solids, which clog pipelines, filters, nozzles in continuous automated lines.
Needs extended stirring or heating, prolongs cycle time and raises energy consumption.
Applicable scenarios: Only simple intermittent batch production, not recommended for standard automated lines.
EDTA-4Na
Advantages:
Rapid dissolution adapts to high-speed continuous feeding of automated equipment.
High solubility supports concentrated liquid dosing, cuts packaging, storage and transportation costs.
No sediment or lumps, stable fluid delivery, reduces equipment maintenance and downtime.
Applicable scenarios: First choice for all automated production lines (industrial detergents, textile, alkaline water treatment, liquid fertilizers etc.).
3. Final Verdict
EDTA Tetrasodium (EDTA-4Na) is far better for automated production lines.
Supplementary Tips
EDTA-4Na is strongly alkaline; avoid direct mixing with acidic materials to prevent precipitation.
If your automated line produces neutral/weakly acidic products (food, regular cosmetics), stick to EDTA-2Na and pre-dissolve it in advance with sufficient stirring.