Is Muriatic Acid good for cleaning concrete (driveways, garage or porch slabs) or is it likely to damage it? I have tried ‘concrete cleaners’ but with little success even on what I would expect to be ‘easy to remove stains’, thanks
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Replies
Muriatic acid straight is what we use on pools to clean them before we paint them.
Just be damn careful with it. Make sure you have a source of running water near by incase of splashes. And wear a resporator with filters for chlorine gas.
Nasty stuff but works very well.
If at first you don't succeed...try again! After that quit! No sense being a dam fool about it! W.C.Fields
Muriatic acid will dissolve the cement holding your concrete together. Thus the stains will disappear as well as your driveway or whatever.
It all depends on what constitutes the stain. If it is paint, then try paint remover. For grease try carbon tetra-chloride [or a modern substitute]. Maybe lacquer thinner. If not, toss a match. I've had success using naphtha [enamel deglosser] to remove surfer's wax "SexWax" [parafin, I believe]. Bleach has worked on some graffitti but it takes about 14 minutes.
~Peter, the former accidental janitor
Coke works also. Follow w/ oil dry.
For oil and grease stains, I've had success with a tip I read years ago- wish I could remember where.
Pour enough paint thinner over the stain to cover it and let it soak in. Get a bag of your favorite brand of kitty litter and cover the offending stains with a generous pile of it. Cover the whole mix with a sheet of plastic and weight the corners to hold it down over night. Go out the next day and sweep up the pile.
It seems the evaporating paint thinner pulls the stain out of the concrete like salt on a wound. The Kitty Litter absorbs the thinner and oil as it "pulls out" and the plastic keeps the thinner from evaporating so fast that it doesn't do it's job.
I've had to repeat the process on a couple of stubborn stains but I've never found an oil or grease spot this trick failed to remove.
Kevin Halliburton
"One machine can do the work of fifty ordinary men. No machine can do the work of one extraordinary man." -Elbert Hubbard-