Basic Principles of Gas Chromatography

Martin R. Hackman

NJ - DEP

Office of Quality Assurance

THE CHROMATOGRAPHIC PROCESS - PARTITIONINGTHE CHROMATOGRAPHIC PROCESS - PARTITIONING

(gas or liquid)MOBILE PHASEMOBILE PHASE

STATIONARY PHASESTATIONARY PHASE

Sampleout

Samplein

(solid or heavy liquid coated onto a solid or support system)

GC Methods

Parameter Group Method Compounds

• SDW05.13000’s EPA 502.2 VOC’s

• SDW05.24000’s EPA 551.1 Cl-VOC’s/Pests

• WPP05.04000’s EPA 604 Phenols

• WPP06.03000’s EPA 625 SVOC’s

• SHW06.21000’s SW-846 8141A Org-P Pests

Instrumentation

Injection Port - Sample introduction

Manual - Direct Injection

Automated - Autosampler

- Purge and Trap

Temperature Control

• Isothermal • Gradient

0

40

80

120

160

200

240

0 10 20 30 40 50 60

Time (min)

Tem

p (

deg

C)

Instrumentation - Oven

Columns

• Packed

• Capillary

Polarity

Non-polar

Polar

+-

Phases

Instrumentation - Detectors

Destructive

• Mass Spectral (CI/EI) [625]

• Flame Ionization (FID) [604]

• Nitrogen-Phosphorus (NPD) [8141A]

• Flame Photometric (FPD) [8141A]

• Electrolytic Conductivity (Hall/ELCD) [502.2]

Instrumentation - Detectors

Non-Destructive

• Thermal Conductivity (TCD)

• Electron Capture (ECD) [551.1]

• Photo Ionization (PID) [502.2]

Chromatograms - 551.1

Chromatograms - 604

Supelco® PTE-5 Supelco® SPB-50

m- Cresol