Lee Marotta, Mike Baylerian, Alan Gallaspy, Andy Tipler, Miles Snow

When your GC/MS is out of

Breath

Helium and the use of alternative GC

carrier gases

Page 2

Outline

Some background to Helium: where it comes from, who uses it, how

much it costs and why we should be concerned about consuming it.

How to reduce wastage of Helium on a GC: method optimization and

elimination of leaks.

Using alternative carrier gases. Benefits and trade-offs. Compatibility

with detectors, especially MS.

Conclusion and questions.

Background

Page 4

Element Abundance (%)

Hydrogen 73.90

Helium 24.00

Oxygen 1.07

Carbon 0.46

Neon 0.13

Iron 0.11

Nitrogen 0.10

Silicon 0.07

Magnesium 0.06

Sulfur 004

Others 0.07

A1689-zD1

Space (or to give it a more technical

name, 'The Universe') is big. Really Big.

Douglas Adams, The Hitchhiker’s Guide to the Universe

Page 5

Helium is constantly being formed in

stars by thermonuclear fusion of

hydrogen at ~15,000,000K

Page 6

Gas Abundance (%)

Nitrogen 78.08

Oxygen 20.95

Argon 0.93

Carbon Dioxide 0.04

Neon 0.0018

Helium 0.00052

Methane 0.00017

Krypton 0.00011

Hydrogen 0.000055

Water ~ 1

NASA

The Earth:

Mostly Harmless: a small, blue-green

world in one of the less fashionable

sectors of the galaxy.

Douglas Adams, The Hitchhiker’s Guide to the Universe

Page 7

Helium is able to Escape the Confines of Gravity

Helium

goes this

way

Page 8

Helium Formation on Earth

Produced by the radioactive decay of isotopes of uranium and

thorium

This is a very slow reaction

Current natural reserves have been generated over the last 4.5

billion years!

The earth’s crust contains 0.0008% helium

Some natural gas contains up to 7% helium

Page 9

Helium Mining

USA (83%)

Algeria (11%)

Canada

Poland

Russia

Qatar

Amarillo, Texas

Page 10

Applications of Helium

Application Usage

(%)

Lifting 15.1

Magnetic Resonance Imaging (MRI) 15.0

Welding 14.9

Chromatography 7.6

Heat Transfer 6.4

Leak Detection 5.6

Pressurizing 5.5

Fibre Optics 4.1

Diving Mixtures 4.0

Superconductors 2.9

Inert Atmospheres 2.7

Nuclear Magnetic Resonance (NMR) 1.3

Other 14.9

Page 11

The Price of Helium in the USA

United States Bulk Helium Cost vs. Year

0

2,000

4,000

6,000

8,000

10,000

12,000

14,000

1930 1940 1950 1960 1970 1980 1990 2000 2010

Year

Pri

ce p

er

Metr

ic T

on

(U

.S. $)

Price no longer

controlled by US

government

Price of Helium dramatically

Increasing every year

Source: U.S. Geological Survey

Page 12

One Man’s View - Helium will be Exhausted in 8 Years!

"The government had the good vision to store helium, and the question now is:

Will industry have the vision to capture it when extracting natural gas, and

consumers the wisdom to capture and recycle? This takes long-term vision

because present market forces are not sufficient to compel prudent practice.

When they stick that straw into the ground to suck out oil and gas, the helium

comes out, and if it doesn't get captured it drifts into the atmosphere and is lost.

Helium production is a side industry to oil and natural gas, an endeavor that

nobody wants to lose money on."

Lee Sobotka, Ph.D., professor of chemistry and physics in Arts & Sciences

at Washington University in St. Louis, December 2007

Government not funding the mining of Helium leaving it to industry

A lot of helium is not capture during drilling for oil, etc.

Page 13

Helium Balloons

Balloon retailers, which use about 7 percent of the (USA)

national supply, are already promoting conservation.

The International Balloon Association, a Wichita, Kan.-

based group of balloon manufacturers and distributors, is

asking its members to consider alternatives to helium, such

as good, old-fashioned air, particularly for balloons that don't

have to float. It's also promoting products that can extend

the float time of a balloon and decrease helium use by

about 25 percent.

Helium drifting away

St.Louis Post, January 2008

Page 14

Helium in Gas Chromatography

Despite conflicting opinions and statistics, there is growing

concern about the availability and cost of helium

Chromatography consumes 7.6% of the world’s helium supply

As chromatographers, we can make a significant impact on the

total amount of helium consumed by:

• Eliminating wastage

• Using alternative gases such as hydrogen and nitrogen

As instrument vendors we can design and provide tools and

techniques to assist users in this enterprise

Saving Helium

Page 16

Causes of Helium Waste

Deliberate (e.g. from injector split settings in GC method)

Non-Deliberate (e.g. from leaks)

Both of which can be easily addressed by the user

Page 17

What Lifetime is Expected from a Standard 8000L Cylinder?

Mode Column

Flow Rate,

mL/min

Split flow

Rate,

mL/min

Septum

Purge Flow

Rate,

mL/min

Estimated

Cylinder Lifetime

with 1 GC, days

On-column

capillary (POC)

2 - - 2771

On-Column

Capillary (PSS)

2 10* 3 369

Packed column 20 - - 277

Packed Column 50 - - 111

Splitless injection 2 25** 3 180

Split injection 2 25 3 185

Split injection 2 50 3 101

Split injection 2 100 3 53

Split injection 2 200 3 27

Split injection 2 500 3 11

* A small split flow is recommended to help keep the injector swept and clean

** The split vent is closed during injection so total usage is slightly reduced

Page 18

Cost of a Cylinder Containing 8000L 5N-Grade Helium

Country Example Cost (€)

USA 35

Taiwan 117

Germany 146

France 150

Italy 160

China 299

Brazil 507

Page 19

The PerkinElmer Clarus Gas Chromatographs with PPC Pneumatics

Clarus 500

Clarus 600

All these have support for

automated leak limitation

and detection

Page 20

Conserve Helium by Turning Down the Split Flow Whenever Possible!

Use a simple timed event on the Clarus 500 or 600 GCs to reduce the split flow rate after the injection is complete

For a lab of 5 GCs running with 200mL/min split flows, this single action, that takes just a moment to enter, will:

• Save up to €10,000/year in helium costs

• Eliminate up to 60 cylinder exchanges/year

• Contribute significantly to helium conservation

Page 21

Sources of Leaks

Tank regulator

Laboratory plumbing

Connections to the GC

Internal plumbing in the GC

Injector septa and o-rings

Column ferrules

Column breakage

Page 22

Buy a Helium Sniffer – it will Save You Thousands of Euros!

Never use soap solution to locate leaks!

Clarus GC PPC Split Pneumatics – Split Mode

Solenoid

Valve

Flow Sensor

Pressure

Sensor

Proportional

Valve Proportional

Valve

Injector

Column

Controller

Controller

• Leaks are detected by a sudden loss in pressure and the system is subsequently shutdown

after 2 minutes

• An automatic system leak-check may be performed at the start of each run – again the system

is shutdown after 2 minutes if a fault is detected

• In split mode, the PPC controller regulates the gas-flow into the injector so leakage will never

exceed this rate.

Page 24

PPC Split Pneumatics – Splitless and Leak-Check Mode

Solenoid

Valve

Flow Sensor

Pressure

Sensor

Proportional

Valve

Injector

Column

Controller

Monitored Output

Page 25

Automatic Leak Checking with PPC

Flow rate into injector

checked as a pre-run event

If flow rate exceeds limit,

GC will shutdown

Prevents major loss of

carrier gas

Also reduces explosion risk

with hydrogen carrier gas

Page 26

Summary of Options to Reduce Helium Wastage

Reduce or eliminate split flows when not needed

Detect and eliminate leaks

Page 27

A Proposed Charter for Chromatographers

Chromatographers

• Know how much helium you use (your Helium Footprint)

• Use instrument features to reduce splitting when it Is not

necessary

• Be mindful about detecting and eliminating leaks

• Consider using alternative carrier gases

Vendors

• Provide tools for reducing and tracking helium usage

• Optimize injectors and detectors for use with other carrier gases

• Develop example applications and proof statements with other

carrier gases

• Encourage end users to reduce helium usage

Using Alternative Carrier

Gases

Page 29

Content

Review of available gases

Advantages and tradeoffs

Compatibility with injectors, columns and detectors

Mitigating the risks in using hydrogen

Effect on performance

Special considerations for MS

Options for ATD and HS

Review of Carrier Gases

Gas Helium Hydrogen Nitrogen Cost Expensive Low cost Low cost

Speed of

chromatography

Medium Fast Slow

Chromatographic

efficiency

Low Medium High

Flow permeability Low High Low

Supply Pressurized

tank

Pressurized tank or

electrolytic hydrogen

generator

Pressurized tank

or nitrogen

generator Safety concerns Highly explosive

Hydrogen cylinders

Pros

Can keep up with substantial demand if necessary

Can usually get spare cylinder quickly

Cons

Safety concerns with flammability especially with large leaks or catastrophic failures

Inconvenient (and can be dangerous) to move and exchange

Hydrogen generator

Pros

No heavy high pressure cylinders to lug around

Low internal volumes at low pressure means small hazard potential

Intelligent shutdown in the event of a fault

Cons

High initial cost

May not have spare generator on hand for backup

Need to assess demand accurately

Injector and Column Compatibility

Injector Considerations

• Hydrogen – Very low viscosity requires low inlet pressure.

– Potential problems with short (30 m or less), wide bore columns (530

μm).

– MS further limits column dimensions

– Potential Problems with splitless and pressure pulse injections.

• Nitrogen - Optimal linear velocity requires low inlet pressure.

– Potential problems with short (30 m or less), wide bore columns (530

μm).

– MS further limits column dimensions

– Potential Problems with splitless and pressure pulse injections.

Injection Method Considerations with MS

Detector Compatibility

Combustion Detectors (i.e. FID, FPD)

• Constant flow mode is preferable

• Baseline may change in constant pressure or velocity type

operation.

• Remember to combine carrier flow for total hydrogen for

combustion

NPD

• Requires constant flow of hydrogen at ~1 mL/min

• Hydrogen is not a good choice for a carrier gas

Single Quad MS

• Hydrogen potential reduces sensitivity by 2x

• High vacuum column outlet may constrain injector pressure

settings

MS System Performance

GC Sample Handling Devices

Hydrogen is not an acceptable carrier gas for thermal

desorption type sample introduction.

Hydrogen is not an acceptable carrier gas for pyrolysis sample

introduction, since a heated wire glows red hot in the injector.

Hydrogen is an acceptable carrier gas for headspace sample

introduction when using appropriate safety measures

(including a special hydrogen needle).

Detailed Hydrocarbon Analysis using Helium and Hydrogen

70 Minutes

160+ Minutes

Helium

Hydrogen

More

Available

Time

Column Efficiency

Column efficiency

(hence peak shape

and resolution) is very

similar in this region

for all three gases

Clarus GC PPC Systems Support Velocity Control and Display

Capillary column carrier

gas may be controlled by

setting the pressure, flow

or velocity.

In each mode of control,

the current values of all

three are displayed in real

time

Method migration with carrier gas velocity control

5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0 10.5 11.0 11.5 12.0

Helium

Hydrogen

Nitrogen

30cm/s at 20°C/min

Same separation with the

same method with all

three gases!

Can I migrate methods with flow or pressure carrier gas control?

7.0 7.5 8.0 8.5 9.0 9.5 10.0 10.5 11.0 11.5 12.0 12.5 13.0 13.5 14.0 14.5 15.0 15.5 16.0 16.5 17.0 17.5 18.0 18.5 19.0 19.5 20.0 20.5 21.0 21.5

Helium

Hydrogen

Nitrogen

Constant Pressure at

10°C/min with Initial

Velocity of 30cm/s

Same separation if the

initial velocity is the

same!

Clarus GC PPC Split Pneumatics – Split Mode

Solenoid

Valve

Flow Sensor

Pressure

Sensor

Proportional

Valve Proportional

Valve

Injector

Column

Controller

Controller

• Leaks are detected by a sudden loss in pressure and the system is subsequently shutdown

after 2 minutes

• An automatic system leak-check may be performed at the start of each run – again the system

is shutdown after 2 minutes if a fault is detected

• In split mode, the PPC controller regulates the gas-flow into the injector so leakage will never

exceed this rate.

Automatic Leak Checking with PPC

Flow rate into injector

checked as a pre-run event

If flow rate exceeds limit,

GC will shutdown

Prevents major loss of

carrier gas

Also reduces explosion risk

with hydrogen carrier gas

Ensure systems are leak free (and re-check them periodically)

Use an in-line snubber if you are using high pressure cylinders

Use a hydrogen generator rather than a high pressure cylinder

Route gas vents away from the instrument

Use PPC pneumatic systems to limit and detect leakage and to shutdown the system if necessary

Install capillary columns so that they don’t rub against other surfaces

Things the user can do to minimize risks in using hydrogen

Special considerations for GC/MS

Use caution when venting

• Shut down carrier gas before MS pumps

Use extra caution after a power failure or unexpected failure of

vacuum system

• Shut down carrier flow

• Do not turn MS system on immediately

• Allow hydrogen to dissipate

• Use a nitrogen purge accessory

Page 46

GC/MS Drinking Water Tuning

Helium Hydrogen

Mass 525.1 525.2 525.3

DFTPP

Helium

DFTPP

Hydrogen

51 10-80% of base peak 10-80% of base peak n/a 46.6 43.9

68 <2% of 69 <2% of 69 <2% of 69 1.3 1.6

69 n/a n/a present 52.0 45.6

70 <2% of 69 <2% of 69 <2% of 69 0.1 0.5

127 10-80% of base peak 10-80% of base peak n/a 56.6 47.1

197 <2% of 198 <2% of 198 <2% of 198 0.2 0.7

198 base peak or >50% of 442 base peak or >50% of 442 present 100.0 100.0

199 5-9% of 198 5-9% of 198 5-9% of 198 5.4 6.3

275 10-60% of base peak 10-60% of base peak n/a 23.2 24.3

365 >1% of base peak >1% of base peak >1% of base peak 1.9 2.5

441 Present and < 443 Present and < 443 <150% of 443 79.5 78.8

442 base peak or >50% of 198 base peak or >50% of 198 present 64.7 75.3

443 15-24% of 442 15-24% of 442 15-24% of 442 19.7 17.7

Summary

There is a compelling need to switch GC methods away from using helium • Cost

• Sustained supply

• Free up helium supplies for ‘more important’ purposes (e.g. MRI)

There are feasible alternative carrier gases • Hydrogen

• Nitrogen

Chromatography equivalent to that obtained with helium carrier is possible with hydrogen or nitrogen on GC systems that control and monitor gas velocity through the GC column.

Although there is risk of an explosion when using hydrogen, this will be very small if the following are followed: • Hydrogen generator

• Use PPC pneumatic controllers

• Ensure that systems are leak-free

• Route split vents etc. to the instrument exterior

• Use a hydrogen sensor in the GC oven

Thank you!!!!!