Re: methanizer

You should give Peak Labortories a try.  Sorry, I don't have the contact
info with me and it would probably be difficult finding them on the web as
they are very small.  If you have an interest I can certainly get the info
to you.  You could also try Trace Analytical (which is a part of SAES and
should be quite easy to find).  I believe they use the same material.

The advantage to their methanizer is that it is not Ni and therefore will
not be poisoned by O2.  Ni will have a very big downside for your
application given an air matrix.  I've forgotten the exact material Peak
Labs uses, so sorry can't help you there.  But it is quite tolerant of O2
and in fact O2 can be injected on it to clean it up and regain lost
sensitivity from long-term use.  Currently we are obtaining low PPB MDL's
with this material for CO and CO2.  The low MDL's are accomplished with a
monster sample size (5 mL), so you can see that the capacity of the
methanizer is quite good.  Also, when things are running well we see very
close to a 1:1 relationship between CH4 and CO2 sensitivities.

One downside is it's use requires some plumbing changes.  I don't have a lot
of experience with the practical aspects of the Ni methanizers, but in the
case of this material you must plumb a small stream of H2 into the
methanizer.  In our machine, the methanizer is simply plumbed in series with
the column and the methanizer discharges into the detector.  A tee is put
just upstream of the methanizer inlet and H2 is plumbed into the tee.  Note,
this H2 is in addition to the combustion H2 so changes are necesssary there
as well.  Another potential stumbling block to modifying an existing 5890 is
the need for a quite hot heated zone for the methanizer.  If I recall
correctly, ours is running at about 380 deg C.

If you are interested drop a line at [EMAIL PROTECTED]  subsititute et
for __.   I'll give you some contact info.  Auch darfst Du Deutsch
schreiben, wenn es Dir besser passt.  Jetzt verlerne ich verdammt schnell
die Sprache, und ich freue mich ueber jeder Gelegenheit, mein Deutsch zu
pflegen...

Tschuss,

Scott McFarlane




"Joern Pardemann" <[EMAIL PROTECTED]> wrote in message
news:[EMAIL PROTECTED]
> hi colleagues,
>
> where can we purchase a "methanizer" to convert CO in a gc effluent in
CH4,
> witch can be detected by a fid? Can this device connected to agilent 5890
II
> gc/fid?
>
> Any experince with self-build methanizer ?
>
>
> We have to determine CO in air by a gc method (according to a german vdi
> standard).
>
>
> Thank you in advance
>
> best regards
> joern
>
>