3 replies to this topic

We would like to use Glycolic Acid, 70 % Solution (30 % is water), for natural stone and ceramic etching purposes.
Because it is produced with an enzymatic procedure our acid is absolutely pure and clean. What we would like to know is if there's someone that could help us in increasing the Glycolic acid corrosive/etching properties when diluted at i.e. 4% in water. Any help is needed

[sgkim]

Hi,
Details shall be given for the etching method. But if you are going to find the more acidic organic materials than GA, include the following in your trial list: Oxalic Acid (HOOC-COOH), Acetic Acid(CH3COOH), Glyoxylic Acid(HOCCOOH), Mono-,Di-, or Tri-chloacetic Acids(ClxHyCCOOH, x=0~2;y=0~2). Special care should be taken for the last two, though. Waiting for your test result I remain.

sgkim

Thanks for your reply. What do you think about 4% Glycolic acid (pure at 70 %, liquid form) and 2 % of formic acid (at 98% pure) diluted in water? Our goal is to sightly increase the etching properties on natural materials such as granite, marble, ceramic, etc... but still having a non dangerous product. Thanks for your comments and replies

[sgkim]

I am not sure organic acids can quickly etch silica- or alumina- based natural stones. You can raise the temperature for the faster reaction. Refer to the following ionization constants at ambient temperatures.
It may not be so difficult to treat these as inorganic acids. Each unit price and molecular mass shall also be considered for the evaluation. (Multiply each figure by each equivalent mass, divide by unit price and compare.)

Acetic Acid:1.75E-5, Glycolic Acid:1.48E-4, Formic Acid:1.70E-4, Chloro Acetic Acid:1.4E-3, Oxalic Acid:5.9E-2,

sgkim