FID, ECD & Pyrolysis

FID

Flame Ionisation Detector (FID) is the most common detector paired with gas chromatography instruments for analytical applications. FID uses a flame to ionise carbon containing organic compounds. Following separation of the sample in the GC column, each analyte passes through a flame, fuelled by hydrogen and zero air, which ionises the carbon atoms. Once formed, the ions are collected and measured as they create a current at the detector’s electrodes. The current is produced as the detector collects the charged ions. The current is then converted to an electrical signal in picoamperes (pA) or millivolts (mV).

ECD

Electron capture detectors (ECD) are typically used in environmental testing for detecting PCB’s, organochlorine pesticides, herbicides and various halogenated hydrocarbons.

Pyrolysis

Pyrolysis is the thermo-chemical depolymerisation of materials at elevated temperatures in an inert gas. The degradation profiles, or pyrograms, elucidate polymeric composition and structure. Pyrolysis-gas chromatography-mass spectrometry is a powerful technique for polymer characterisation especially when combined with the separation advantages offered by comprehensive two-dimensional gas chromatography.