Charcoal made in SKC Inc. is sealed in a glass tube. One tube is enough to
treat about 4ml of water. It is very convenient and effective. The address is:
334 Valley View Road, Eighty Four, Pennsylvania 15330.
Paul Brooks wrote:
> First I would like to thank all of you who replied on the storage of IAEA
> standards. The information was very useful.
> We are using FM Gas Bench for 18O equilibrations with 0.2% CO2 in
> Helium. This method usually works very well. Unfortunately we have a
> batch of water extracted from grass leaves that report results that make no
> sense. It appears that some of them actually generated CO2, while other
> took it out of the atmosphere! Running them twice made no difference and
> yet other samples and standards in the run analyzed very well.
> It has been suggested that this is probably due to contamination from
> organic volatiles in the sample, and that we should add some activated
> charcoal to each sample, shake them and then re-equilibrate them. I am not
> familiar with this method. Has anyone else ever used this and do they have
> a reference and suggestions as to the type of carbon?
> Thanks in advance,
> Paul D. Brooks,
> Dept. ESPM-ES,
> 147 Higard Hall MC 3110,
> UC Berkeley, Ca. 94720-3110.
> phone (510)643-1748,
> FAX (510)643-5098.