Vinegar may be used to remove paint off concrete. All you have to do is heat a half cup of vinegar. Allow the hot vinegar to seep into the paint for 15 minutes. Remove the paint with a paint scraper as it begins to bubble. Let the concrete air dry and repeat as needed.
The heat from the vinegar removes some of the pigment in the paint, allowing it to come out in the water. The white color of the vinegar should not be visible on the concrete after heating and cooling it in this way. However, any residual vinegar smell after heating and cooling the concrete in this way will disappear when the concrete has time to dry.
Concrete can also be cleaned with equal parts lemon juice and water. Heat the mixture until it boils then pour it over the concrete surface and let it sit for 30 minutes before washing away the residue with a hose. If your concrete was black, this method will also remove it.
You can also use soap and water to clean concrete. Make a solution of 1 part household laundry detergent to 9 parts water. Soak a clean cloth in the solution and wipe down the concrete to remove any dirt or debris. Rinse the cloth in warm water and air-dry it before using it again.
Finally, you can use steel wool to scrub concrete.
A more in-depth examination of how to remove paint from concrete
To remove undesirable paint from concrete, scrape away as much as possible, thoroughly clean the surface, use paint thinner, scrub the paint, and then remove the thinner. You can go back and forth between these stages as needed.
Using a Soda Blaster to Remove Paint from Concrete: A soda blaster employs granular sodium bicarbonate to swiftly remove tenacious paint off concrete and other surfaces without hurting the substance beneath. You may buy industrial-grade sodium bicarbonate when you hire the blaster. Regular baking soda is ineffective.
Removing paint from concrete may be a difficult task. Concrete is porous and rough, resulting in a textured surface on which paint adheres easily. Muriatic acid removes stains and paint off concrete quite efficiently, but it can etch the surface if left on for too long or proportioned wrong. Acid-based cleaners should never be poured into drains as this could cause corrosion of metal pipes. Instead, use a detergent such as sodium percarbonate or trisodium phosphate to wash your car's exterior before washing it with acid.
Concrete surfaces can also be cleaned with warm water and a scrub brush; be sure to rinse well after cleaning. If you want to get rid of even more stubborn stains, consider using a wood cleaner. These products contain chemicals that break down cellulose, which is what gives wood its color and texture. They're not recommended for painted surfaces, however.
Finally, an abrasive material such as sandpaper can be used to smooth out concrete surfaces. Just be careful not to scratch the concrete too much!
If you have an exterior concrete surface (such as a driveway or patio), regular washing with soap and water will usually keep it looking good longer. However, if there are specific areas where dirt and grime tend to collect, such as under a carport or behind siding, those areas might need to be pre-treated with an anti-rust agent before being washed with acid.