Concrete is a common material for walkways, driveways and garage floors. Over time, the concrete will become dirty, dingy and stained. Furthermore, concrete is naturally porous and can trap items such as oil and grease in its pores. Various chemicals allow you to thoroughly clean your concrete without damaging or discoloring the surface.
The dish soap you use to keep your plates and silverware spotless can clean your concrete without toxic chemicals. Fill a bucket with 1 gallon warm water and add 1/4 cup liquid dish soap. Use a whisk to mix the contents together. Dip a scrub brush in the mixture and begin scrubbing the concrete. Replace the scrub brush with a brush broom to clean the concrete without bending down. Once you are satisfied that you have thoroughly cleaned the concrete, rinse it clean with a water hose.
When the concrete is left damp for an extended period of time, mold can begin to grow, leaving unsightly stains on your concrete which can spread to other areas of your home. Oxygen bleach -- a safer, less toxic alternative to chlorine -- will eliminate the mold and its spores from the concrete. Dissolve 1 cup of oxygen bleach in 1 gallon of warm water. Scrub the mold off the concrete with a soft-bristled scrub brush saturated in the oxygen bleach mixture. After you have removed all traces of the mold, rinse the mixture off the concrete with a water hose.
A solvent typically used as paint thinner, mineral spirits will remove a variety of stains from concrete including tar and paint. Mineral spirits is a flammable liquid that you must keep away from open flames and sparks. Before using mineral spirits to remove tar or paint from concrete, put on a pair of rubber gloves and scrape as much paint and tar off the surface as you can with a paint scraper. Scrub the remaining tar or paint with a nylon scrub brush dipped in the mineral spirits. Rinse the concrete clean with a water hose.
A mineral acid derived from hydrogen chloride, muriatic acid is a dangerous liquid that you should only use as a last resort. The acid -- as well as its accompanying fumes -- can damage a variety of items including metal. Furthermore, breathing in the fumes may damage your nose, throat and lungs while the acid itself will burn skin. Before using muriatic acid, wear the proper safety attire such as heavy-duty work gloves, long sleeve shirt and pants. Pour 5-percent muriatic acid -- available at home improvement centers -- directly on the oil and grease stains and begin scrubbing vigorously with an old broom. Once you have removed the stains, rinse the concrete with a water hose.