Kristine,

I think there's a nice paper in Pier de Groot's book, which you may 
want to refer to.  But, basically, you need to adjust the pH to between 
3 & 4, thereby preventing any bicarbonate [let alone carbonate] species 
from being present in the water.  You should get a carbonate-free 
precipitate that way.


On May 15, 2006, at 3:00 PM, Kristine Nielson wrote:

> Under what conditions does BaCO3 precipitate?  I ask because a while 
> ago I tried precipitating BaSO4 from gulf of mexico porewaters and had 
> a coprecipitate with carbon in it (at least, that's what the EA told 
> me), but everyone I asked claimed BaCO3 shouldn't precipitate at all.  
> I'm rather relieved to know the compound at least exists, and would be 
> grateful for any information on how and where it forms.
>  
> Thanks,
>  
> Kristine
-- 
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Steve Nelson
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Brigham Young University
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801-422-8688

"Guns don't kill people, Dick Cheney kills people."
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