How do I clean concrete with hydrochloric acid?
Unfortunately, Muractic in most commonly sold formulas [in pool supply stores] is somewhere in the neighborhood of 30-33% hydrochloric acid. When diluted 50% you STILL have 15+% hydrochloric acid concentrations.
The sand left on a surface after etching or cleaning with acid is the fines [small grain sand] that is an essential component of the concrete. The Acid attacks the lime which binds a concrete together and the sand is the first to become unbonded in this process. Acid is an enemy of all concretes and other alternative solutions should be employed, to keep from causing a whole host of other long term problems to your concrete. Not just surface degradation problems but also a lowering of the pH and promoting moisture travel into a matrix. These two conditions promote formation of corrosion cells on reinforcing steel.
A much better alternative can be found @ http://www.StableCrete.com . This product is applied to a cleaned concrete to waterproof the interior capillary system. No more stains or contaminates can enter a matrix and there is no surface filmed formed to make it slick. If a coating is to be applied, any coating will experience better adhesion and will not be subject to a coating blistering or peeling off. After treatment with StableCrete the internal chemistry of a concrete does not migrate Out to a surface to react with an atmosphere or cause a premature coating failure or other conditions like efflorescence.
Many other ways to clean a concrete! If you apply this product to new concrete, it protects it from day one. Extremely Low VOC content for interior uses and can be coated in 48 hours after application, all while being a truly "Green" product! Keep Acids Away From Concrete!
I wouldn’t use HCl on concrete mainly because it tends to leave a residue that will continue to erode the cement. Try diluted muriatic acid (15%). It’s less reactive. As soon as you apply it, brush then rinse right away. It has always worked for me on concrete, calcite brick, clay brick and granite. Be careful. Make sure you have adequate eye protection and gloves. Also make sure the area is well ventilated.
