Hi Elizabeth,

Alunite and pyrite separation is detailed in Wasserman et al. (1992)
Methods for separation and total stable isotope analysis of alunite.
USGS Open-File report 92-9.

As others have said, removing the elemental sulfur is easy, and
should be done before the alunite separation.  CCl4 is supposed to
work well for removing the elemental sulfur.  Elemental sulfur also
dissolves in acetone.

Wasserman et al. recommend gravimetric removal of pyrite before
attacking alunite with NaOH.  Hope this helps.--jim



>Hello all,
>   I am a master's student who has run into a problem with research (the
>usual story.)  I have sediment samples that have fine grained elemental
>sulfur, alunite group sulfates, and pyrite all mixed together. I need to
>find a way to separate the three in order to run stable S analysis.
>Physical separation is a bust and tracking down any other chemical
>treatment has been a vague and frusterating process.  Is there a
>relatively easy way to accomplish the separation without spending a year
>just trying to set up an expensive and complicated separation procedure?
>Any leads to papers, etc. would be very much
appreciated.                           Thanks- Elizabeth Hollingsworth
--
Dr. James P. Greenwood                          phone:  860-685-2545
Research Assistant Professor &                  fax:     860-685-3651
Visiting Assistant Professor
        http://planetary.wesleyan.edu
Dept. of Earth & Environmental Sciences
Wesleyan University
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