How do you get the driveway whiter?

I know this question is one most of us know the answer to but I’m trying to think outside the box. We do a lot of pressure washing concrete driveways. Most of these driveways are older and after cleaning the driveway…it looks good but it’s kinda of uneven in terms of color. Looks like there are some slightly different shades in certain parts of the driveway. It doesn’t have anything to do with uneven pressure washing. We’ve use oxalic acid as well and it really didn’t change anything. I’m just wondering if it is just old and the only thing you can do is paint it or somethin’.
Is there a detergent or a paint that you can make it whiter. (don’t want to use muratic acid…that etches not cleans).

Older concrete just won’t turn white like it was poured last week. In the concrete cleaning business, one of the hardest things to get across to a customer is that there’s a difference between “clean” and “white”.

Having said that, there are very limited things you can do with old concrete. You mentioned muratic and oxalic, have you tried a spraying a sodium hypochlorite solution after cleaning? Sometimes that can brighten the surface a few shades.

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Micah, thanks for replying, if you mean sodium hypochlorite as bleach…yes I’ve tried it, but it really didn’t make much of a difference. This driveway we cleaned wasn’t made well in the first place. I used even some gutter zap and it didn’t brighten it up a little.
You are right about the hardest thing to get across to a customer is the difference between clean and white.
I haven’t tried TSP yet knowing that has some environmental implications, but I think that may work a little

If oxalic acid won’t do the job the concrete probably won’t come any cleaner or more white.

will it hurt cured concrete?

what will bleach do?