You can clean stains from cement without using harsh or toxic chemicals. Harsh chemicals can slowly erode cement if used repeatedly. There are home remedies that will work to remove rust stains from cement. Remove the rust stains as soon as possible, before the stains have time to work more deeply into the cement.
Remedies for Rust
A number of household items, such as lemon juice, borax, Dawn dishwashing liquid, baking soda and even laundry soap, can work to remove rust stains from cement. Before you proceed with cleaning the entire stain, be sure to test the home remedy on a small area.
Squeeze a lemon directly onto the stain and allow the juice to sit for five to seven minutes. Use a stiff-bristled brush to remove the stain, and hose the cement clean.
You can use borax powder to clean many items around the house. To remove rust stains from cement, mix 1/4 cup of borax with a gallon of hot water and apply the solution to the stain. Use a stiff brush to scrub the rust stain until it starts to disappear. You will want to use a power washer, if possible, to clean the borax off the surface.
Another remedy that works well for removing rust is a mixture of lemon juice and baking soda. Use equal parts of both products and apply the mixture to the spot for 15 minutes. Use a scrub brush to scrub the rust stain away. Be sure to thoroughly rinse the entire area that has been cleaned.
Dawn dishwashing liquid can also be used to clean up rust stains. Mix 1/4 cup of Dawn liquid in a gallon of hot water. Scrub the stain until you start to see the stain lift. Use a power washer to spray off any remaining Dawn from the cement.
Cement is a very porous substance until it is sealed. If the rust stain is on a patio or driveway you will want to keep any metal furniture or other metal objects off the surface until it is cleaned and sealed with a product such as Thompson's Water Seal.