Glycolic Acid For Concrete Cleaners And Removers

Glycolic acid (hydroxyacetic acid) is the first member of the series of alpha-hydroxy carboxylic acids, which means it is one of the smallest organic molecules with both acid and alcohol functionality. The product is manufactured by PureTech Scientific, previously Chemours Glycolic Acid Division, in the United States (Belle, WV) with excellent supply stability and outstanding quality.

 Glycolic acid for concrete and masonary cleaners

 

Glycolic acid is preferred in concrete cleaners and removers as it combines the essential cleaning attributes, required acidity, and necessary metal complexing capability for concrete cleaners and cement dissolving formulations.   Glycolic acid is an excellent alternative to corrosive acids, such as HCl, and more efficient than organic acids, such as citric and acetic acids, in concrete and grout removers.

Why Glycolic acid for concrete cleaners and dissolvers?

 

Glycolic acid is featured with a small molecular size and excellent water solubility that enables deep penetration in concrete residues and adequately reacts with particles from within. Due to its low corrosivity, it can be safely used on metal and equipment surfaces without causing etching or damage. It is also easier to dispose of than many other acids, such as phosphoric and HCl, as it is readily biodegradable.

Glycolic acid attributes in concrete cleaners and dissolvers

 

• Superior cleaning agent at penetrating and loosening concrete
• Excellent complexing agent for calcium and metals
• Low to no corrosion on most metal and coatings
• Improved cleaning efficacy for minerals and metal deposit
• Broad metal sequestering properties
• Excellent solubility of hard water salts (calcium, magnesium, and metasilicates)
• Excellent rinsability with minimal residue on cleaned substrates
• Outstanding formulation compatibility and can be blended with other acids for improved performance
• Easy to handle and readily dilutable to any desired concentration
• Low toxicity, negligible odor, and non-flammable

 

Glycolic acid corrosion study vs. other acids

The following table shows the corrosion rate of glycolic, phosphoric, and hydrochloric acids tested on 1018 carbon steel, 1100 aluminum, 304, and 316 stainless steel. The results are showing the % weight loss at 23°C (73°F) for 48 hours with no agitation.

Concrete cleaners and removers starting formulation

 

Standard Concentrate		Standard Ready-To-Use (Diluted)		Ingredient Examples
Glycolic Acid, 70% Tech Grade	80.0%	Glycolic Acid, 70% Tech Grade	20.0%	PureTech Scientific Glycolic Acid, 70% Tech Grade
Nonionic alcohol ethoxylate surfactant	4.0%	Nonionic alcohol ethoxylate surfactant	1.0%	Tergitol 15-S-9 (Dow)
DPM Glycol Ether	16.0%	DPM Glycol Ether	4.0%	Dowanol DPM (Dow)
Water	0.0%	Water	75.0	Water

   

Low/ No Corrosion Concentrate		Low/ No Corrosion Ready-To-Use (Diluted)		Ingredient Examples
Glycolic Acid, 70% Tech Grade	76.0%	Glycolic Acid, 70% Tech Grade	20.0%	PureTech Scientific Glycolic Acid, 70% Tech Grade
Nonionic alcohol ethoxylate surfactant	4.0%	Nonionic alcohol ethoxylate surfactant	1.0%	Tergitol 15-S-9 (Dow)
DPM Glycol Ether	12.0%	DPM Glycol Ether	4.0%	Dowanol DPM (Dow)
Corrosion Inhibitor	8.0%	Corrosion Inhibitor	2.0%	Rodine 103
Water	0.0%	Water	73.0%	Water

Use instructions of Glycolic acid formulations:

1. Dilute with tap water before use 1:4 (For ready-to-use formulations only)

2. Spray on the substrate or the surface to remove or clean the concrete

3. Wait at least 30 minutes (allowing to react overnight or between shifts is acceptable).

4. Power-wash equipment and parts to remove residual concrete

5. Extremely heavy residuals may require two treatments.

   • Wear appropriate personal protection equipment.

   • As with all acids, it should not be sprayed on hot surfaces.