Rust can be a major issue, especially for concrete. Sealing new concrete is a great preventative measure, but if you want to refresh an existing surface, you must first thoroughly clean it to avoid locking in existing imperfections. Fortunately, there are several methods for removing rust from concrete, and you may already have some of them in your home or office.
Rust stains on concrete can be removed with both household and industrial products. Lemon juice or vinegar may be sufficient for a rust stain on your countertop, but for stubborn or industrial stains on your driveway or warehouse floor, a stronger acid such as hydrochloric acid may be required.
Table of Contents
- Using Acid to Remove Rust Stains from Concrete
- Removing Rust Stains with Alkaline Stain Removers
- Why Are Rust Stains Appearing on Your Concrete?
Using Acid to Remove Rust Stains from Concrete
To remove or at least loosen the rust, most rust stains require the use of an acidic cleaner, such as oxalic acid. The acid aids in stain removal by lifting the stain, making it easier to scrub away the rust stains. Most acids remove rust (an oxide) by converting it to an oxide that can be dissolved in water. The following are some do-it-yourself (DIY) methods for removing rust stains from concrete.
Concrete Rust Removal with Lemon Juice
For lighter stains, lemon juice works just as well as any cleaner. Citric acid in a concentrated form is excellent for removing rust stains. Squeeze the lemon and pour the juice over the stain. Instead of squeezing lemon after lemon onto the target surface, it would be easier to use a store-bought lemon concentrate product. Allow the lemon concentrate to soak in the rust for a few minutes. Scrub the area with a wire brush after about 10 minutes. Rinse it to determine how much of the area has been cleared. If necessary, repeat the procedure.
Rust Removal with White Vinegar
If you have slightly tougher stains, white vinegar instead of lemon juice may be more effective. Simply pour the white vinegar on top of the rusted area and allow it to dry. After the vinegar has dried, scrub the rust stain away with a bristled brush. You can also combine vinegar and salt to boost the acid's potency.
Carbonated Beverages To Remove Rust Stains From Concrete
Carbonated beverages such as Coca-Cola, Pepsi, and others have an average pH of 3.4, indicating that they are acidic. Because the carbon in combination with the acid is strong enough to dissolve metal oxides, simple carbonated drinks are effective rust removers. Allow the drink to sit on the rusted area for a few minutes. Then, either scrub the area or rinse it with a power hose because the sugar in the carbonated drink may make it sticky.
Removing Rust With Hydrochloric Acid
If the rust stain is extremely stubborn and none of the above DIY remedies have worked, you can try hydrochloric acid, but be extremely cautious when using this method. Do not handle the acid unless you are wearing a mask and gloves. You should also dilute the acid slightly. Remember to always dilute the acid with water rather than the other way around.
This process will necessitate quick action because if the acid is left too long, it will stain the concrete surface and turn it a bluish color. Allow the water and acid solution to sit on the rust stain for about 10 minutes before scrubbing and washing the area with a hose. This powerful rust remover should be more effective at removing stubborn rust stains.
Removing Rust Stains with Alkaline Stain Removers
While bases do not always remove rust stains, some mild bases contain other beneficial elements that make them effective cleaning agents.
Baking soda is a mild base that also acts as an abrasive. When baking soda reacts with certain elements, it is known to bubble and fizz. This is why it is used in baking and cakes to allow the crust to rise and be fluffy. When it comes to removing rust stains, baking soda's chemical reaction breaks the bond between the rust and metal, making it easier to remove the oxidized portions.
For this DIY project, combine the baking soda and water to make a paste that will adhere to the surface. It is critical to maintain consistency. The paste must be thick enough so that it does not become runny, but it must also not be too grainy.
Laundry detergent can also be used to remove light rust stains from concrete. Apply a paste of laundry detergent and water to the affected area. The paste will become more potent if the detergent contains baking soda. Make a paste that is thick enough not to run but not so crusty that it dries out too quickly. Allow the DIY paste to sit on the stain for an hour before scrubbing it away with a stiff bristled brush.
Why Are Rust Stains Appearing on Your Concrete?
Check the source of your water if you notice rust stains on your concrete more frequently than they should. When water is drawn from an underground well, the iron content of the water is often high. This iron-rich water may be staining not only your concrete but also any surface it comes into contact with, including your clothes.
Use a concrete sealer to prevent rust damage on the surface and a crack filler to repair any existing cracks. Avoid putting any metal furniture or objects directly on the concrete. Check all of your pipes for any possible leaks that could be exposing your concrete surface to excess water. Constant moisture exposure can cause extensive damage to concrete surfaces. The earlier you detect the leak, the better.
While laying the concrete, keep in mind that the bars supporting the concrete should be non-corrosive. When water penetrates the concrete, the metal begins to corrode, causing rust to emerge from within. You won't have to deal with rust from within the concrete if the metal is non-corrosive.
Rust stains on your concrete floor can be extremely unsightly. Getting rid of rust stains, like many other home improvement projects, is simple if you act quickly and wisely. Most rust stains can be removed with household products. When all else fails, there are plenty of industrial cleaners on the market that can remove such stains.
However, because these chemicals can be harsh, you should always use protective equipment, such as gloves and masks, when working with acid-based cleaners like hydrochloric acid solutions. With all of these tips and tricks for removing rust stains from concrete, you will have no trouble making your concrete look brand new.