I accidentally spilled some wood floor stain on the concrete front steps of my customer's home. How can I remove the stain?
Robert Higgins, an Ormond Beach, Fla.-based independent consultant, answers:
The safest approach is to first discover what the product consists of. Check the technical data sheet to try to identify what the basic products are. If you know at the very least what family the solvent/solid is in, or the waterborne material is in, you can find something to break up the stain and then find something that prevents the stain from simply redepositing back into the concrete, which is typically the biggest challenge.
When dealing with either waterborne or solvent-borne materials, I recommend "like-with-like." If solvents are the vehicle for penetration, these would also be the vehicle for removal; it is just a matter of "collecting" the material(s) that create the staining and penetration in this formulation (and likewise for waterborne products).
For solvent-based stains, one method that works pretty well is making a poultice with mineral spirits and plain Portland cement. The mineral spirits solubilize the solids, and the cement tends to absorb the loosened material. (This isn't much different from a poultice I use for grease and oil stains, but instead of mineral spirits, I use a 50/50 mixture of Portland cement and Tide powdered detergent.)
Products that are linseed-oil-based may be a candidate for using Easy-Off oven cleaner, which "saponifies" the oils, meaning the alkali turns the oils into soap. Another over-the-counter product that may work is Snowcap, which is essentially a powdered form of oxalic acid. The Snowcap is mixed with VERY hot water and a squirt of Dawn dishwashing detergent. For both of these, caution is advised regarding your eyes and inhalation. There is also a potential for etching, particularly with the oven cleaner, so testing of a small area is STRONGLY advised.