To all HF users:
I assume all potential HF users realize that HF is a very toxic and will
take appropriate precautions. However, F may also be hard on the EA-IRMS
system. Last year we had some material delivered for 13C analysis that was
organic matter from soils with the silicates dissolved away with HF, and
then the samples neutralized with some type of base. The samples ruined
our combustion tube, copper tube and we had to bake out the GC column to
get baselines back to normal. The treatment used presumably resulted in
much higher concentrations of F than one would get by just dissolving
carbonates, but I would certainly do a small test run before committing
myself to this method.
Paul Brooks.
At 09:01 AM 2/7/03 +1030, you wrote:
>The HF method might work for geologic materials, but I experienced
>definite losses of soil organic matter that result in the treated fraction
>being several permil more depleted (I ran carbonate-free samples as a
>check and analysed before and after). Thus, be careful with this method
>when applying to younger sediments and soils!
>
>Evelyn
>
>
>Dr. Evelyn S. Krull
>CSIRO Land and Water
>Adelaide Laboratories
>PMB 2
>Glen Osmond SA 5064
>Australia
>
>phone: 61-8-8303-8516
>fax: 61-8-8303-8550
>e-mail: [log in to unmask]
>www.clw.csiro.au/staff/EKrull/
>-----Original Message-----
>From: Pier De Groot [mailto:[log in to unmask]]
>Sent: Thursday, February 06, 2003 9:24 PM
>To: [log in to unmask]
>Subject: Re: [ISOGEOCHEM]
>
>About the carbonate dissolution problem!
>
>I just was reading about another acid, HF, which dissolves carbonate and
>silicates, but seems not to effect the organic materials. This method was
>described by:
>
>Schimmelmann and DeNiro (1984) Earth Planet. Sci. Lett, 68: 392-398.
>
>They used 20 percent HF solution at 25 degrees for 12 hours.
>
>At least a better idea then dissolving the organic material I suggested
>earlier, which method will not work...!
>
>My two eurocents.
>Pier.
>
>************************************************************************Dr.
>Pier A. de Groot
>European Commission
>Joint Research Centre
>Institute for Reference Materials and Measurements (IRMM)
>Retieseweg
>2440 Geel
>Belgium
>Tel. +32 (0)14 571 628
>Fax +32 (0)14 571 863
>e-mail: [log in to unmask]
>
>Visit my WEB-site about my "Handbook of Stable Isotope Analytical
>Techniques" at:
><http://users.pandora.be/handbook/index.html>http://users.pandora.be/handbook/index.html
>
>last update: 19 November, 2002.
>************************************************************************
>-----Original Message-----
>From: Stable Isotope Geochemistry [mailto:[log in to unmask]]On
>Behalf Of [log in to unmask]
>Sent: 06 February 2003 00:16
>To: [log in to unmask]
>Subject: Re: [ISOGEOCHEM]
>
>Jan,
>we've 'experimented' with a number of different techniques and acids and
>the method that gave the most satisfying results (removal of carbonate
>without the loss of organic matter) was by adding sulfurous acid directly
>into the capsule (Ag) containing the sample. The method is well-described
>in the paper by Verardo et al. (1990) in Deep Sea Research, vol. 37, no.1,
>pp.157-165.
>
>Evelyn
>
>
>Dr. Evelyn S. Krull
>CSIRO Land and Water
>Adelaide Laboratories
>PMB 2
>Glen Osmond SA 5064
>Australia
>
>phone: 61-8-8303-8516
>fax: 61-8-8303-8550
>e-mail: [log in to unmask]
>www.clw.csiro.au/staff/EKrull/
>-----Original Message-----
>From: Jan Vermeulen [mailto:[log in to unmask]]
>Sent: Wednesday, February 05, 2003 6:37 PM
>To: [log in to unmask]
>Subject: [ISOGEOCHEM]
>
>Hello All,
>
>Could anyone say to me what acid I can use to liberate CO2 from Soil
>samples who contain CaCO3. I want to remove that CaCO3. It are extracts
>from soils so the carbon is disolved in a water extract.
>
>Kind regards,
>Jan
>___________________________
>Jan Vermeulen
>Laboratory Of Applied Physical Chemistry
>Ghent University
>Coupure Links, 653
>9000 Gent
>Belgium
>
><http://fltbwww.rug.ac.be/isofys/>http://fltbwww.rug.ac.be/isofys/
>tel.: +32 9 264 6048
> +32 9 264 6000
>fax.: +32 9 264 6230
>e-mail: <mailto:[log in to unmask]>[log in to unmask]
>
>The 8th Symposium on
>Biogeochemistry of Wetlands
>
>Will be held from September 14-17, 2003
>Het Pand, Gent, Belgium
>
>More information at
><http://fltbwww.rug.ac.be/isofys>http://fltbwww.rug.ac.be/isofys
>from August 15, 2002
>____________________________
Paul D. Brooks,
Dept. ESPM-ES,
147 Higard Hall MC 3110,
UC Berkeley, Ca. 94720-3110.
[log in to unmask]
phone (510)643-1748,
FAX (510)643-1749
http://ib.berkeley.edu/groups/biogeochemistry/
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