[Ifeffit] XAFS of poly-metals contaminated soil samples

Matt Newville newville at cars.uchicago.edu
Fri Sep 9 13:01:45 CDT 2011


Hi Xia,

--Matt Newville <newville at cars.uchicago.edu> 630-252-0431



On Fri, Sep 9, 2011 at 12:23 PM, Xia Bing <sweetblues at gmail.com> wrote:
>
> Dear members of the mailing list:
> This year we have applied the synchrotron radiation and get the chance to Beijing  Synchrotron Radiation Facility at beamline 1W1B-XAFS. It is the first time to use this equipment to measure our samples. We communicate with the beamline staff for some guideline and help, but they also do not have much experience on soil samples.  Would you like give us some suggestions? If you could, can you supply me some resources like sample preparation or others?
> Now I try to use synchrotron radiation to elucidate some phenomenons of heavy metals in mining area soil. In my soil sample, the Zn is about
> 498ppm and the Cu is about 562ppm, the first step I focus on Zn but the copper concentration is higher than Cu. Will copper  interfere zinc If I use
> XAFS to measure the Zn?

The Cu will add a background signal to the Zn signal, which might make
the measurements take more time, but at these concentrations it should
not  cause any serious problems.

> I plan to use fluorescence detection. The Fe in the sample is at high concentrations (85g/kg), from some literature that might be an issue. Would
> you like to  give me some suggestions in the sample preparation and measurement?

You probably can't extract the Fe from your sample without
significantly changing the soil chemistry.    Putting aluminum foil
(perhaps up to 100 microns) over the detector is a simple but effect
approach.  The Al will absorb the Fe flourescence at about twice the
rate it absorbs the Zn fluorescence.

--Matt




More information about the Ifeffit mailing list