Ask the Expert Question-and-Answer Archive

by Ron Joseph

October, 2002

Environmentally Friendly Paint Removers

Q. Advertisements have been painted on rocks scattered in a fragile ecosystem. What are the possible options for removal of these paints (enamel, lead-based, snowcem)? Some of the options we came across are:

1. using SOY-Gel of FRANMAR CHEMCIAL, INC., 105 East Lincoln #L, P.O. Box 97 Normal, IL 61761
2. rubbing with the cotton dipped in thinner.
3. coating the advertisements with primer then heating. It is envisaged that after heating the paint can peeled of the stone as a skin peeling.

A. Thank you for your question. I'm not familiar with the soy-gel that you mentioned in your email; however, there are some paint removers that are environmental friendly, but I have no idea how they will perform on rocks, or if they will in any way mark or stain the rocks. You will need to test them yourself to make that determination.

A common, very effective paint remover is methylene chloride, but this is NOT environmentally friendly, so you might not want to use it.

A paint remover that apparently works well and is somewhat environmentally friendly is NMP (normal methyl pyrrolidone). The foillowing website will give you the information you requyire on this type of product. In the US, the Air Force often uses it to strip the paints from aircraft. (http://www.lyondell.com/html/products/products/nmp.shtml)

Other alternatives are to abrasive blast the rocks with glass beads, or to blast the rocks with high pressure water to which you add bicarbonate of soda. There are companies that sell both the equipment and the bicarb for this specific purpose.

You will find an abundance of literature on the Internet on paint removal. I went to www.google.com and entered "paint removal stripper depaint" and a host of sites came up.