Muriatic acid can provide that bright white look that new concrete often has. Removes mineral stains. Common mineral stains on concrete are calcium and efflorescence, and muriatic acid can remove both.
The most common acids used to clean concrete and bricks are hydrochloric acid (muriatic) or phosphoric acid. For many years it has been the standard cleaning method to prepare concrete for coatings installations, to remove stains of any type from concrete and to remove concrete slurry or efflorescence from bricks.
Alkaline cleaners are great for lifting oil stains, grease stains, and other petroleum-based stains from concrete. It's an added benefit that you can use it with a pressure washer, making the job that much easier. For an eco-friendly cleaner, we recommend Oil Eater cleaner degreaser (US$15.74, Amazon).
Over time, it can destroy concrete as the acid weakens its structure. This will cause scaling, pitting, peeling, and cracking. If the acid wash gets into the soil, it will evaporate on the surface but remain beneath the surface (just like it does with concrete).
To clean and etch concrete, mix one part muriatic acid to 10 parts water. Brush or spray the acid solution on the concrete, wait eight to 10 minutes, then neutralize the acid by spraying the surface with a mixture of one cup of ammonia in one gallon of water.
Mix your muriatic acid.
In terms of a gallon, these means adding about 3 ounces of muriatic acid to a gallon of water. You can add an additional 3 ounces of acid if needed, but don't add over that much. High concentrations of muriatic acid can etch concrete, glass, remove paint, dull chrome, and cause other issues.
Muriatic acid is strong enough to etch concrete, but it can also cause severe injury and/or damage property when used improperly. Always wear protective clothing, rubber gloves, boots and goggles or a face shield when handling acid. Avoid breathing acid vapors.
Start by saturating the stained concrete surface with a product like ProClean Neutralizer™. This helps neutralize the acid stain and prepares the surface for thorough cleaning. 2. Gently scrub the neutralizer into the concrete using a soft nylon bristle brush, taking care to wear your spiked shoes during this process.
Pressure washing is one of the fastest, most effective ways to get your concrete white again. Concrete can change color over time due to pollen, algae, or dirt buildup, but a good pressure wash can easily remove dirt and stains and make your concrete look new again.
Driveways and Sidewalks
If you don't have access to a pressure washer, you can use Super Clean, a hose and a garage broom to get similar results. Spray the area down with cold water, spray on some Super Clean and let it sit a few minutes. Work it into the concrete with the garage broom, and rinse with the hose.
The acid washing of concrete is a requirement after the concrete has cured sufficiently, in order to remove surface efflorescence and to open the pores before sealing. This will help the sealer to penetrate and result in a superior bond between the sealer and the surface.
Sulfuric Acid (H2SO4)
oz. of 31.45% HCl. It takes 2% more sulfuric acid to equal muriatic acid (by volume) to accomplish identical pH and alkalinity reduction. Sulfuric acid is a comparable alternative to muriatic acid.
In fact, vinegar removes mold from concrete better than bleach. Bleach will only remove the top layer of mold, causing the mold to return.
This will help the sealer to penetrate and result in a superior bond between the sealer and the surface. Sealing after acid washing provides long lasting durability and enhances or deepens the colour of your blocks, it is important to seal the acid washed area as it offers excellent protection against staining.
Add 1 part of 33% hydrochloric acid to 2 parts water to make a 10% solution. Always add acid to water and wear eye protection, acid proof gloves and all other appropriate protective equipment. 4. Apply liberally to cover the floor using a large watering can.
The reason for washing the residue is to neutralize the acid. So long as you properly neutralize and rinse the concrete well a couple of times, it should be fine. Note: If you do not properly neutralize the stain, then the sealer will lose it's bond, which will then have to be stripped and re-applied.
To maintain the lighter color of a concrete driveway, many homeowners turn to cleaning with bleach, but you should not power wash with bleach because it can damage your pressure washer.
The quick answer is yes, power washing can degrade a concrete surface.
The inorganic compounds which are useful as concrete dissolvers generally include inorganic acids such as hydrochloric, phosphoric, hypochlorous and carbonic acid. Salts of these acids and alkalies such as sodium-hydroxide, sodium bicarbonate and ammoniumsulfate are also eifective.
One of the most common methods of removing stubborn dirt and stains on outdoor concrete floors is by using muriatic acid. Muriatic acid is one of the most common substances when it comes to household cleaning and disinfection.
Muriatic acid: mix 3 to 4 parts water with 1 part acid, or follow label instructions for a 10% concentration (15% for hard, smooth concrete). These solutions are for etching the concrete. If you're just removing mineral deposits (efflorescence), use a much weaker mix (10:1 or 16:1 for muriatic acid).