Over time, concrete surfaces such as patios, driveways and sidewalks, will experience hard-to-remove stains. Rust, grease and oil buildup, sometimes cannot be removed with everyday cleaning products. Use muriatic acid as the last resort to remove difficult stains. Muriatic acid is a very dangerous acid and must be treated as such. It can damage even burn anything it touches. Precautions must be put into place before using muriatic acid.
Preparing to use Muriatic Acid
Read and follow the instructions carefully on the muriatic acid label.
Water all plants in the nearby area and then cover them for extra protection. If not, the acid can burn the plants.
Wear safety goggles, respirator-mask, long-sleeved shirt, pants, rubber boots and acid-resistant gloves.
Fill a 5-gallon bucket with water just in case the muriatic acid gets on your skin or eyes. You will need to wash the area immediately. Also have baking soda and lime available to help neutralize the acid.
Check the weather report. If it is going to be a windy day, do not use the muriatic acid. Wait until a calm day. Also never use muriatic acid indoors. You need proper ventilation for it can burn your eyes and throat.
Remove Stains With Muriatic Acid
Dilute the muriatic acid with one part acid to 10 parts water in a bucket. Pour the acid into the water not the water into the acid.
Apply the acid to the stained area using a scrub brush or a plastic sprayer that you can dispose of afterward. Let the acid stand for five minutes and then apply again until the stain has been removed.
Rinse thoroughly with a water hose and attached sprayer to dilute any acid residue. Make sure to spray away from any plants or grass. Let the area dry for 24 hours.
Apply a sealant to your concrete to avoid any future stains.