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Does anyone know if it is possible to remove or lessen a large (2 ft) stain caused by a diluted solution of muriatic acid on white concrete? I accidently/stupidly caused this while cleaning the pool filter cartridges and it leaked onto my neighbors patio! I’d really appreciate any advise.
Beatrix
In this FHB Podcast Segment, the team chats about the best way to build a paintable surface over an old wall.
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OK, I've never used muriatic acid, so I have a stupid follow up. What color is the stain? I've only heard it's used to clean concrete, so wouldn't it have just turned more white? If so, just add more acid, and clean your neighbors' patio for them. ;)
*The stain makes that part of the patio look wet. A chemist friend said to try Windex to neutralize the acid. I'm afraid to experiment and end up making it worse, but I have every intention of fixing it for them. I'm feeling awfully humble right now.
*Beatrix: Concrete is actually attcked by muriatic (hydrochloric) acid. That is why it is used to remove mortar from walls and the like. If you washed down the area right after the spill, there is likely to be little residual acid there.I will make a couple of thoughts. With them, or any of the suggestions offered, try a small area first. If that works, try a slightly larger area.If there is residual acid, your best bet for neutralization is baking soda. Mix it with a little water and put it on. If it fizzes, there is acid; keep adding until the fizz stops.I suspect that the "wet look" is due to the acid eating away some of the surface, leaving it smoother than the rest of the patio. Look at, or even feel the concrete. You might see a difference. If that is all the problem is, a little weathering will erase the effect. A quick check would be to wet down the whole area with a hose. If the surfaces blend together, then likely the surface will probably age nicely.If you have a distinct color difference after wetting, I don't know. Let's cross that bridge when we get to it. And do let us know what happened, good or bad. ----Please!!!!
*John,Thanks for your help. I tried the baking soda-it helped a bit. I called a few concrete guys but they all said that I was out of luck. So I went for it with the Windex, thinking that I had nothing to lose-b it worked!!!!A gallon of regular Windex, lots of scubbing with a hard brush and now you can just barely see the stain. I am no longer the neighbor from hell. Yes...there is a God!!Beatrix
Did you apply pure windex (non diluted) then scrub the acid spot with a brush then rinse with water? I’m trying to lessen the color and visibility of a muratic acid stain on concrete as well.
Jack,
You’ll just have try it yourself as these posts are old.
Best of luck.
Alright, thx
I was looking for solution to a similar problem at my home. I will try Windex.