MGDA•Na₃ (Methylglycinediacetic acid trisodium salt) is a readily biodegradable, eco-friendly chelating agent widely used in daily chemical production. Its primary function is to sequester metal ions (e.g., Ca²⁺, Mg²⁺, Fe³⁺) to improve product stability, performance, and shelf life. It can be applied at multiple stages of the production process, as outlined below:
1. Raw Material Pretreatment Stage
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Water Softening:
Added to process water to chelate hardness ions (Ca²⁺/Mg²⁺) before formulation, preventing interference with surfactants or active ingredients. -
Purification of Raw Materials:
Chelates trace metals from natural/mineral ingredients (e.g., clays, plant extracts) to reduce impurities and ensure batch consistency.
2. Formulation & Mixing Stage
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Precipitation Inhibition:
Added during emulsion preparation or blending to prevent insoluble soap/scum formation (e.g., calcium stearate), maintaining product clarity and homogeneity. -
Stabilization of Active Ingredients:
Protects oxidation-sensitive components (e.g., vitamins, enzymes, perfumes) by deactivating metal ions that catalyze degradation. -
Enhancing Surfactant Efficiency:
Softens water in situ, allowing anionic surfactants (e.g., SLS, SLES) to perform optimally without dosage loss.
3. Post-Processing & Quality Control
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pH Adjustment Compatibility:
Remains effective across a broad pH range (acidic to alkaline), making it suitable for use before or during pH correction. -
Color & Odor Protection:
Prevents metal-induced discoloration or rancidity in finished products during storage.
4. Application-Specific Examples
| Product Category | Role of MGDA•Na₃ |
|---|---|
| Liquid Detergents | Prevents surfactant precipitation, improves foam stability, and boosts stain removal. |
| Shampoos/Conditioners | Enhances cleansing efficiency, reduces residue on hair, and stabilizes fragrances. |
| Skin Cleansers & Creams | Maintains emulsion integrity, prevents rancidity, and reduces irritation potential. |
| Household Cleaners | Boosts performance in hard water, prevents scale deposition on surfaces. |
Key Advantages over Traditional Chelators
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Biodegradability: ~80% degradation in 28 days (OECD 301 standards), unlike persistent phosphonates (e.g., EDTA, ATMP).
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Eco-Toxicity: Low aquatic toxicity, compliant with EU Ecolabel and similar regulations.
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Broad Compatibility: Stable with oxidizers, enzymes, and most cosmetic ingredients.
Usage Recommendations
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Typical Dosage: 0.1–1.0% (w/w) in final formulations, adjusted based on water hardness and ingredient sensitivity.
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Addition Point: Usually introduced during the aqueous phase mixing, prior to surfactant addition.
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Storage: Stable under normal conditions; no special handling required.
Environmental & Regulatory Notes
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Accepted in eco-certifications (e.g., EU Ecolabel, Nordic Swan).
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Preferred in “green” formulations as a sustainable alternative to EDTA, NTA, or phosphonates.
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Compiles with major regulatory frameworks (REACH, FDA indirect food contact applications).
Conclusion
MGDA•Na₃ is a versatile, environmentally sound chelator applicable throughout daily chemical production—from water pretreatment to final product stabilization. Its use enhances product performance while aligning with modern sustainability goals, making it a growing choice for detergents, personal care items, and household cleaners.