HEDP is highly acidic. Can we use in alkaline degreasing chemicals?
Yes, HEDP (1-Hydroxyethylidene-1,1-diphosphonic acid) can be used in alkaline degreasing formulations, despite being highly acidic in its pure form, because:
Key Points:
- Chelating Function in Alkaline pH:
- HEDP forms stable complexes with metal ions (Ca²⁺, Mg²⁺, Fe²⁺/Fe³⁺), even at pH 9–12, which is typical in alkaline degreasers.
- It prevents scale formation (anti-scalant) and stabilizes hard water salts.
- Neutralization in Formulation:
- In alkaline degreasers, HEDP is partially or fully neutralized using sodium hydroxide or potassium hydroxide, converting it to its sodium salt form (Na-HEDP).
- This form is stable in alkaline environments and retains its chelation capacity.
- Advantages in Alkaline Degreasing:
- Keeps bath clean by preventing metal soap deposition.
- Controls water hardness interference.
- Improves cleaning efficiency by preventing redeposition of soil.
Recommended Use in Alkaline Degreasing:
- HEDP dosage: 0.1% – 0.5% (as active acid), neutralized with NaOH in formulation.
- Compatible with non-ionic and anionic surfactants.
Conclusion:
Although acidic in raw form, HEDP is chemically compatible with alkaline systems after neutralization and is widely used in alkaline degreasers, water treatment, and detergent systems for its strong chelating and stabilizing properties.
HEDP IS HIGHLY ACIDIC. IF WE USE IT IN ALKALINE PRODUCT THAN IT IS NOT GIVEN GOOD RESULTS.
Although acidic in raw form, HEDP is chemically compatible with alkaline systems after neutralization and is widely used in alkaline degreasers, water treatment, and detergent systems for its strong chelating and stabilizing properties. Please go through the last section of the article.