Over time, a residential driveway can become an eyesore from leaked motor oil, tire marks and other stains. Muriatic acid, also referred to as a form of hydrochloric acid, is an extremely effective concrete cleaner -- with emphasis on "extreme." Muriatic acid, typically diluted with water, reacts with the alkalinity of the cement and "etches" the surface, dissolving surface stains and foreign material. The basic safe procedure to clean with muriatic acid is easy to follow and will help restore the appearance of your driveway's surface.
Put on all protective gear, including boots, gloves and glasses.
Mix muriatic acid with water for the desired solution, based on the manufacturer's recommendations.
Pour a small amount of the acid-water mixture carefully onto the concrete surface, beginning with a concentration on specific stained areas of the driveway. Allow the mixture to saturate the stained area for approximately 10 minutes to dissolve the material.
Scrub and spread the acid solution over the concrete surface using a floor brush. Use a wire brush on difficult stains or built-up material. Add more acid mix as needed.
Rinse the driveway thoroughly with clean water.
Repeat Steps 2 through 4 for stubborn stains or problem areas.
Things You Will Need
- Plastic bucket
- Muriatic acid
- Stiff-bristled floor brush
- Wire brush
- Rubber gloves
- Rubber boots
- Safety glasses
- Avoid rinsing the muriatic acid solution into planters or grassy areas adjacent to the driveway to prevent poisoning the plants.
- Muriatic acid is a dangerous and corrosive liquid that should be used with extreme care and only as a last resort after milder cleansers or power washing has proven ineffective. Even diluted muriatic acid will dissolve cloth or leather and presents a burn hazard for exposed skin or eyes.
- Use only a plastic bucket and dilute the acid in clean water. To prevent splashing or spillage when mixing the acid solution, add the acid liquid to the water; do not add water to the acid.