How to fix concrete colour after acid washing?

[PatDIY_Dad]

I did a bit of a rookie error and tried to clean up some stains with hydophloric acid mixed with some water on my driveway concrete

Poured it on and scrubbed it with a bristle brush and washed it off with water

Now the stain is gone but the concrete is a different colour. (could be the original colour I guess) but it sticks out even more now

Is my only option now to acid wash the whole area?

I used this stuff:

https://www.bunnings.com.au/bondall-5l-hydrochloric-acid_p0960235?store=6415&gad_source=1

They sell at bunnings

[MitchellMc]

Hi @PatDIY_Dad,

I'm not sure about that one. We can see the original lighter shade of your concrete through the comprised sections of the painted coating. You seem to have a light blue area at the bottom and a deeper blue at the top, with a transition line through the middle. You then have a much darker stain from the acid in the middle.

I can't imagine that acid would cause bare concrete to turn darker, so perhaps it was some interaction with the painted coating. If anything, it would typically lighten the colour of concrete. Acid washing the whole area might be an option, but I am concerned that it will become a big mess.

You might like to look towards a product such as Rust-Oleum 3.78L Concrete and Garage Recoat Primer for compromised painted coatings and then a compatible topcoat like Rust-Oleum 3.78L Concrete And Garage Floor Paint, essentially re-painting the whole area.

Please let me know if you have any questions.

Mitchell

[PatDIY_Dad]

Thanks for the reply

its not painted its coloured through concrete

Might try give it a good wash first with boiling water and dishwashing soap see if that makes any difference. Probably wont though

[MitchellMc]

It would be worth giving it a go @PatDIY_Dad.

The colour looks fairly inconsistent for coloured concrete. It appears that the colour is only on the high or low spots, which gave the impression of paint. See how you have light blue, darker blue and then grey? Grey would be the uncoloured concrete. Perhaps it's just the picture, though. I'll point to the grey in the image below, which is seen over your entire picture. The top right corner is a fairly solid colour, but the rest seems quite streaky. 

Mitchell

[PatDIY_Dad]

What you are seeing it just dirt thats all

I just washed it. When it dry's ill take a another picture but from higher up so you can see the whole area