Chromatography Forum

Hi all, my environmental lab is considering switching our carrier from Helium to Hydrogen for the GCMSs. Anyone have any experience with this transition; instrument parameters, tuning problems, etc? And, was anyone successful in getting it to work? I've talked with other chemists who indicate this is a problem-filled venture. The price of helium is killing us!

This is a common topic, there is even another current thread on it, and have a look in the archives.

Peter

Lin
I would discourage you from using hydrogen for GC-MS unless you work only with hydrocarbons and stable VOCs. Hydrogen activates liners hence promotes decomposition of semi VOCS at the injector and its release metals from oxides at the ion source hence the mass spectra of some compounds become "different" plus the sensitivity is reduced and on top of this you have safey issues.
Hydrogen should be considerred if helium is missing and not due to price issues. If your injector and column consume on the average 30 ml/min it amounts to 43 liters per 24 hours. Even at a price of $30 per cubic meter (how much do you pay?) it is only $1.3 per day which is far lower than other expences and negligible compared to salaries.

I add this also for others browing this thread: Are you using the gas saver option? If you have an instrument that runs split injections, the gas saver can make a significant difference in gas usage. And, take a leak sniffer to all connections between the bottle and the instrument every now and again. When changing a gas cylinder, check from the connection to the bottle through every fitting that can be shaken or moved as you move lines around.

Note that you can switch to nitrogen as the purge gas for the volatiles instruments at least.

Hey Lin,

We have a lab in a different city, which uses a hydrogen generator for the carrier gas on one of their mass specs. I'm very interested what it would take to put our mass specs on hydrogen too. If I ever get around to it, I'll be sure to let the forum know how it went. The biggest trouble I've heard is that you may have to rerun all your standards for the spectra library.

Please keeps us updated if you make the switch and of any problems you may discover.

The Agilent rep who was installing our GC-MS was telling us about how helium is collected as a byproduct from fossil fuel extraction, and the easily available supply is rapidly contracting. She said there are murmurs that within a decade, it won't just be an issue of price - it'll be simply a matter of availability, and labs will have to start redeveloping methods for hydrogen once that comes along.

Exaggeration or reality?

There is an interesting article in the July 16th edition of Chemical & Engineering News about the helium supply.

http://cen.acs.org/articles/90/i29/Heli ... Users.html

It discusses the current shortages and an optimistic outlook for supplies through the year 2030 (at which point I will be long ago retired)