the closest to this is shipboard sampling of sea water using a chelating
resin. Frankly, I feel it is not worth the effort and the chance of
contamination without a proper mobile lab such as is available onboard ship.
Why is it such an issue to filter in the field. C and S probably don't require
much filtration and certainly don't require much sample (not with modern
equipment - we use no more than a few ml for C here) and the lab in Pretoria is
set up for 400-500 ml samples for Pb isotope analysis (Sr only requires a
portion of this and both get concentrated at the same time on the coluns I set
up for this purpose). It is easy to filter this amount in the field with
Swinnex filters and syringes.
Quoting Henk Coetzee <[log in to unmask]>:
> We are busy with a study where it would be nice if we could
> precipitate/extract C, S, Sr and Pb from water in the field. The major
> time consuming factor here is filtering before precipitation or
> extraction. This is complicated further by low Pb concentrations in a
> lot of the water that we would be sampling and the need for large
> samples. At the moment our procedures all require sampling, followed by
> filtration (ideally in the field but generally in the lab) and the
> chemistry in the lab. Has anyone tried this?