Removing fuel stains from concrete

[Pinecone]

To be clear, I am NOT recommending using it in your hangar with the plane in there.

Just that once it is applied and stops foaming, there is no longer any acid left.

[M20F]

VEVOR Demolition Jack Hammer 2200W Jack Hammer Concrete Breaker 1400 BPM Heavy Duty Electric Jack Hammer 6pcs Chisels Bit w/Gloves & 360°C Swiveling Front Handle for Trenching and Breaking Holes

https://a.co/d/4B43alw

[Pinecone]

That may be the only answer, due to concrete being porous.

[Shadrach]

18 hours ago, Fly Boomer said:

Depends somewhat on the pressure washer.  I have seen one damage concrete.  Either too strong pressure washer, or too weak concrete.

This is why that have different heads and or settings.  My family owned a Hotel for many years. We had an industrial strength steam pressure washer that would have taken flesh off bone with the most aggressive head.  However, at right setting it would take everything from gum to oil stains off of concrete with no visible damage. All of our concrete was cleaned weekly.  The 35 year old concrete at our property looked fresh and healthy when we sold in 1998.  It is now positively filthy after decades of neglect but it is still perfectly intact.  The correct tool for cleaning concrete is a pressure washer. Every property management company knows this.   If you drive through any major city early in the morning, the facades and sidewalks are being pressure washed. A little solvent may be helpful for stubborn stains.  Using acid is going to cause deterioration...how much will depend on how it is used. . Using a pressure washer will not cause damage unless it is misused.  I think the OP is looking for a shortcut where there really isn't one. The correct solution is obvious. 

[rbridges]

I know for oil stains, you need a degreaser and something to absorb it.  Concrete is porous, so something needs to pull out the dissolved material.  Otherwise it settles back in and stain persists.  Something that dissolves fuel, doesn't evaporate super fast and covered with kitty litter would be my recommendation.

 

[Shadrach]

2 hours ago, rbridges said:

Something that dissolves fuel, doesn't evaporate super fast and covered with kitty litter would be my recommendation.

MEK…

[jlunseth]

I vote with Shad. I haven’t had industrial grade experience, but I have plenty of concrete patio and I clean it every spring with a pressure washer. It does a pretty good job and I have even cleaned some diesel fuel spills on old asphalt with it, although that never comes 100% clean. Mine is a cold water pressure washer, there are hot water washers that would probably do an even better job. Probably you can rent one locally. I would put a degreaser on it like Simple Green, let that work, and then pressure wash it with a hot water washer. We use muriatic acid on fiberglass to clean stubborn stains on our sailboat and it does a spectacular job with even fuel stains, but I would be reluctant to do that on concrete because of the chemistry (acid against lime).