phosphoric acid rust removal field test

[Keyxs]

Great thread, and good info.
No hijack, and no connection with the company, but good product..

Test Piece was a rusted fuel line protector sleeve, and caps, no pretreatment, or bushing, just dumped them into the stuff and walked away.

After an hour immersed.

 

[bluebikerblan]

Lot's of sources for diluted Phosphoric Acid rust removers including a product from Dairyland carried by your local Tractor Supply outlet.

 

[meanstreakmark]

Carpet cleaners who perform tile and grout cleaning services use phosphoric acid as one of the cleaning agents. That being said, look for a supply house that caters to them. Typically, what is available through the supplier is a 25% solution; and it will contain some mild surfactants (detergents) to help with wetability.

 

[Darin Jordan]

I just picked up a gallon of concrete etching solution from The Home Depot for $17.00.... it's main ingredient, aside from water, is Phosphoric Acid....

 

[PetesPonies]

The concrete etch from Home Depot is 50-50 I believe. Thats a good concentration.

 

[Darin Jordan]

The concrete etch from Home Depot is 50-50 I believe. Thats a good concentration.

That's good to know. I soaked the tank with Evaporust for about 3-days, and it did a relatively good job, but I still round some particulate matter around the petcock mounts and down in the nooks and crannies so I'm going to do the Phosporic treatment as a second run through. Hopefully it'll finish the job and get this tank back on track.

Once it's clean, I have a can of Red-Kote that I'm going to be using...

 

[Darin Jordan]

SO... I attempted to clean out my tank the rest of the way this afternoon. I poured into a dry tank, which had previously been treated with Evaporust and didn't quite get as clean as I'd have liked, a gallon of Concrete etching from Home Depot.

I immediately noticed that the tank started getting pretty warm... After about 10 minutes, the acid started boiling out in a brownish frothy foam, emitting some kind of dark brown gas and overflowing all over what once was a beautiful black paint finished...

I quickly poured out the acid and got the hose and flushed it all out. Tank is much cleaner now, for sure, but the paint is going to have to be redone. I certainly wasn't expecting that reaction as I haven't heard it mentioned here anywhere. I'm suspecting that it was due to a reaction with whatever the Evaporust left behind???

Anyhow, the tank is clean now and I'll now prep it for the Red-Kote and do that before I move forward with getting the tank repainted.

 

[August]

Sounds like I'm going with what you're doing, the 50/50 solution. I'll be redoing my paint anyway, so should I end up getting the same reaction as you, I'll be okay. But sorry to hear about your paint.