Car corrosion reaction question.

[Celephais]

I recently cleaned some corrosion off of my battery with a saturated baking soda solution, and noticed the resulting substance to be an odd brown color. A friend of mine tracked some of it into the house, and I'm a bit concerned regarding how toxic it might be? I've got cats, so this is specifically why I'm worried.

 

I've been told that the corrosion is lead sulfate, and that the sulfate + the baking soda would create a reaction of PbSO4 + NaHCO3 = Pb + CO2 + NaSO4*H2O

 

Is that valid?

Edited February 5, 2010 by Celephais

[NightHawkIL]

Well since nobody else is answering I'll give my less than expert opinion. You likely have a variety of lead salts, lead, and rust/dirt from the car. Unfortunately, lead salts are not very soluble. You should be able to clean what little could have been tracked in from a single battery with soap and water. Use gloves, as lead salts are quite poisonous. Even so, I very much doubt there is enough there to hurt your cats after a quick wash.

 

If by chance the reaction you posted took place, much of the lead salts will have been broken down into metallic lead - which is much less poisonous.

[Celephais]

The majority of the corrosion I cleaned off was almost replacing(!) the metal that makes up the "bar" that fits over the battery to keep it in place.

 

Is it likely that in that case, it's probably a higher concentration of iron oxide, as opposed to lead oxide, which as I've come to find out have a very similar color?

 

Also, tracked in is probably not the best descriptor. I've only noticed small orangish spots here and there in the carpet. Will vacuuming it be enough, you think?

Edited February 6, 2010 by Celephais

[NightHawkIL]

Well, iron(III) oxide and lead(II) oxide are both orangish, though iron is a very deep red orange, whereas the lead oxide is almost white. Either way, in your case what you cleaned off is very likely almost entirely iron oxide. It poses no threat. Vacuuming will likely not remove the stains unfortunately. I've had some success cleaning iron oxide with a little vinegar. I believe that would even help get rid of any lead salts if by chance they are present.