Dear Steve,

At 17:45 07.10.98 +0100, you wrote:
>Dear List Members,
>
>I'm interested in the possibility of measuring the H, C and O isotope
>composition of cellulose and wonder if anybody is in a position to help
>me with a couple of queries.
>
>(1) Would  anybody be able to supply me with a copy of the following
>item- Edwards, T.W.D. & Elgood, R. 1992. Extraction of sediment
>cellulose for oxygen and carbon isotope analysis. Technical Proceedings
>28.0, Environmental Isotope Laboratory, University of Waterloo, Ontario.
>9pp.
>
>(2) Is anybody aware of an alternative to the benzene-methanol
>extraction for the preparation of cellulose extracts. I'm not too happy
>about the benzene (unless there's no alternative).
>
>Cheers,
>
>Steve Crowley
>
>Stable Isotope Laboratory
>University of Liverpool

At the University of Bern (Dept of Climate and Environmental Physics) we
use a 1:1 toluene-ethanol mixture (5-7 hours in a soxhlett distilation
apparatus) to extract the resins and lipids from fine grounded
(approximately 0.1mm) wood. This is the first step we use in order to
"produce" alpha-cellulose out of our wood samples. The next steps involve
NaClO2, acetic acid and NaOH.

Actually I don't know whether it functions for extraction of sediment
cellulose, but for wood samples it functions very well. And toluene-ethanol
are certainly less toxic than benzene-methanol.

Hope it will help. If you want more details about our technique, let me know.

Cheers,

Silvio


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