Chromatography Forum

Dear all,

Is there anyone here uses hydrogen as GC carrier gas on GC-FID system? Will use that shortly however no any experience on that. Besides the safety issue, is there any other thing need to pay attention to?

Thank you!
SG

There are many UK customers using Hydrogen carrier as it is the most efficient carrier gas and less expensive than Helium. If used with care you should have no problems. Newer GCs with DPFC (Digital Pressure and flow control) will switch off in the event of a major leak which is an added safety feature. In 15 years of GC I have only heard of one Hydrogen "accident". A user of a Carlo Erba 4000 series (circa 1970) set their GC up and went for coffee. On their return they were puzzled to see all their colleagues hiding under benches ! They had installed the column without ferrules, not done a leak check , just lit the FID and left. Once the GC filled up with Hydrogen (head pressure flow control) it ignited. Fortunately the spring loaded door held (design feature, not guarenteed) and no-one was harmed. The engineer was asked to visit to write off the GC for insurance purposes. Unfortunately the GC in questions was fine , if a little circular rather than square and the GC and was put back into service, still with Hydrogen carrier.

Here in our lab we used for many years H2 as carrier. We stop using it because of the limitation of our H2 generator (125 mL/min), not enough for 5 FIDs and one column with a split 1:40. We live on 3rd world so haven't money to solve the problem adding a new generator.

But resolution was fine, many times I miss its separation power.

I recommend it, using with care.

REgards

DL

With sensible leak checking hydrogen is an excellent carrier gas - low cost and fast separations come standard.

BUT - if you are using a 530 micron column the flow in the column will be a significant fraction of the total hydrogen entering the FID - and you need to adjust the FID fuel gas accordingly. Also, you will need to run in constant flow mode (if you have that option on the GC), otherwise you will get dramtic baseline drift as the flow through the column changes during a temperature programme.

Peter

While Hydrogen is the best gas for the fastest separations it has a major downside that is often overlooked. It is chemically reactive and it reduces metal oxides in the injector glass liners which become active and decompose many pesticides, drugs, explosives and other delicate samples.

Thank you guys for your sharing. Your experience is very useful to me to make decision if I employ hydrogen or not....

Look at this link........

http://www.restek.com/advantage/adv_1998_02_koni.asp

It is very detailed. Thank you very much!