Dear Isogeochemists,
We need information for using Schutze reagent (I2O5 on silica gel).

We are trying to analyze both 13C and 18O of CO (< 1 nmol), using CF-IRMS
for CO2. We bought Schutze reagent (LECO corporation, MI, USA) and
constructed a helium-purged system which exclude CO2 etc. from a gaseous
sample, convert CO to CO2 using the reagent (ca. 1 gram) and then load onto
a GC column of our GC/IRMS. We found, however, significant CO2 blank is
derived from the reagent. The blank level was 10 - 20 pmolCO2/min/g, under
helium flow is 100 ml/min. Without the regant, the blank is fall into less
than 3 pmolCO2/min.

This is the first time for us to use the reagent. Is this a usual state for
the reagent? Or do we have to make some pre-treatment before we use the
reagent? Any related information on the matter will be appreciated. Thank
you in advance for your help.

Cheers,
Urumu





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Urumu Tsunogai, Ph. D
Lecturer
Dept. Environ. Science & Technology, IGSSE
Tokyo Institute of Technology
4259 Nagatsuta-cho, Midori-ku,
Yokohama 226-8502, Japan
Tel. +81-45-924-5585
Fax. +81-45-924-5518
E-mail [log in to unmask]
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