Posted by: tvasailor | April 2, 2022

Helium Conservation in GCMS and GC Applications

Return to Homepage

Currently and in several times in the past, the cost and supply of helium in GCMS and GC applications can be cause for concern. Several manufacturers have taken notice and started to supply products and technical advice to address the problem.

Conserve Helium or Switch to Hydrogen or Even Nitrogen in GCMS and GC Applications? The most straigtforward approach is to conserve helium by minimizing helium useage in GCMS applications. This avoids having to make changes to current well established analytical methods. A more radical approach is to switch from helium to hydrogen or even nitrogen for GCMS. The latter shows promise and is discussed below, but one needs to consider the challenges. The use of hydrogen in pure GC applications is much less of a challenge and is commonly employed.

Thermo has a clever product, iConnectTM Helium Saver, for their Split/Splitless TraceTM GC systems. It uses helium for the injection and nitrogen for all other aspects of the injection process to conserve helium. They state that it can dramatically increase the lifetime of one cylinder of helium:

-3.5 years continuously used 24/7/365 for GC-MS
-14 years when you either shut the helium off of divert to nitrogen overnight and on weekends

Link to their brochure
Link to their website
Development Work Leading to Product
Excerpt Description of Injection Process from Agilent Manual

Agilent has created many useful documents and products. They compare the advantages of using Hydrogen for GC separations compared to helium and even discuss the use of nitrogen as a carrier gas in GC, but not recommended in GCMS. They also discuss a study that dramatically reduced helium useage in their Little Falls Site. For example, a GC-MSD (GC-MS) using their Gas Saver hardware increased the lifetime of a helium cylinder from 109 to 252 days.

Link to Little Falls Site Study

Another Agilent presentation describes in detail the use of their 7890 Helium Conservation Module which uses nitrogen during standby. In one application, it extended the use of a cylinder of helium from 2 to 12 months.

7890 Conservation Module Information

Other Agilent Resources include:

Agilent Cost Saving On-Line Calculator
On-line overview from Agilent On-Line

Chromtech Eco-Saver for All GC Systems

Chromtech Device Link

Markes Mulitigas Thermal Desorber for GCMS

Markes Multigas Desorber

*****SWITCH from Helium to Hydrogen or Even Nitrogen for GCMS? *****

Manufacturers discuss the pros and cons of using hydrogen or even nitrogen as a carrier gas instead of helium for GC-MS analyses. Most say limitations, but Leco, Bruker, Shimadzu, and Anatune say not so much a problem?

Topics discussed include chemical noise, detection limits, changes in analyte EI spectra (reduction), tailing, in-situ source cleaning, self-CI, etc. when hydrogen or nitrogen are substituted for helium and how to minimize or avoid such limitations.

Leco
Agilent
LCGC
Thermo
Shimadzu
Bruker
Anatune

Nitrogen was shown successfully used as a carrier in a Shimadzu thermal desorption GC-MS method. In addition, other information found including ideas (e.g. 200 eV vs. 70 eV) for inceasing sensitivity, thoughts on problems in method development, and work in progess on EPA method development. A good article describes maintaining speed in GC analyses using nitrogen, but does not discuss applications in GCMS as a carrier gas.

Leco with hydrogen notes an increase in S/N in all components in a complex tee leave extract as shown in the link to their study above. This is impressive noting a significant decrease in analysis time by a factor of 5 while maintaining good retention indices compared to helium and good EI library search quality. Also, no discussion of any signficant delay times in source “acclimation.” Possibly due to their somewhat unique “open-style” EI source?

Bruker with hydrogen says their SCION GC-MS with the Helium Free Analyzer option offers good pumping and injector design. They indicate that all 76 components in EPA Method 8270 including nitro and nitroso compounds gave high quality searches against the NIST library using AMDIS deconvolution. Others noted that nitro compounds can yield spectra showing the in-source reduction of nitro compounds.

Agilent Jet-Clean technology actually uses hydrogen in instruments that use helium as a makeup when the instrument is at idle to remove build-up of “dirt” in the source. Thus, using hydrogen as the carrier might also offer similar advantages by minimizing source cleanings.

Agilent Jet-Clean info for “in-situ source” cleanings

****************************************************************

Videos

Agilent Webinar (Jim McCurry)
Another Agilent (Shannon Coleman discusses part of Little Falls Study shown above)
Yet Another Agilent (Bryan White)
Thermo
Shimadzu
Axion (switching GC from He to H2)
C&EN Podcast World Supply Outlook

MRI and NMR useage can also be decreased by new technology. Many years ago our Cryrolect GC-IR had a similar approach.

MRI and NMR
Limiting Amount Needed in Seimins MRI

Party and Weather Balloons account for about 7% of the useage of helium per year. I saw in several places on the internet, but surprised it was such a realtively high number.

Return to Homepage


Responses

  1. […] New:  Conserving Helium in GCMS and GC Applications […]

  2. Can u send me pdf file of these articles

    • all i have is linked on my page


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

Categories

%d bloggers like this: