Product Code:
TECHNICAL FEATURES
Weak organic acid used in restoration for its ability to complex metal ions, adjust pH, and facilitate the controlled removal of surface deposits.
Composition:
- Chemical formula: C₆H₈O₇ (anhydrous) / C₆H₈O₇·H₂O (monohydrate)
- Soluble in water and polar solvents
- Active in mildly acidic solutions (adjustable pH)
- Non-toxic, biodegradable, compatible with other chelating agents (e.g., EDTA, ammonium bicarbonate)
Appearance:
- White or colorless crystalline powder
- Odorless, acidic taste (not relevant in conservation)
- Soluble in water (up to 60 g/100 ml at 20 °C)
- pH of a 1% solution: approx. 2.2
Main uses:
- Controlled removal of calcareous encrustations and soluble salts from stone surfaces
- Deoxidation of metal surfaces (copper, bronze, iron) through metal ion complexation
- pH adjustment in aqueous mixtures or gels used for surface cleaning
- Chelating and buffering agent in treatments combined with ammonium bicarbonate, EDTA, or sepiolite-based poultices
- Natural, biodegradable, and low-impact alternative to more aggressive mineral acids
