The document describes various gas chromatography detectors including the Flame Ionization Detector (FID), Thermal Conductivity Detector (TCD), Electron Capture Detector (ECD), Thermionic Detector (TID), Electrolytic Conductivity Detector, Photoionization Detector (PID), Atomic Emission Detector (AED), Flame Photometric Detector (FPD), GC-MS, and GC-IR. It provides details on the principles, advantages, and disadvantages of some of the main detectors.

1. GC - DETECTORS

2. GC Instrumentation

3. GC- Column

4. GC- Detectors
1. Flame ionization detector ( FID)
2. Thermal conductivity detector (TCD)
3. Electron capture detector (ECD)
4. Thermionic detector (TID)
5. Electrolytic conductivity detector
6. Photoionization detector (PID)
7. Atomic Emission detector (AED)
8. Flame Photometric detector (FPD)
9. GC-MS
10.GC-IR

5. Ideal characteristics of a detector
• Adequate sensitivity
• Good stability & reproducibility
• Linear response
• Temp range from room temp to 400⁰C
• Short response time
• High reliability
• Selectivity
• Non destructive

6. Flame ionization detector

7. FID
• Few hundred volts applied between burner tip
and collector electrode
• Resulting in generation of current
Advantages: 1. High sensitivity
2. Linear response & low noise
3. Rugged and easy to use
Disadvantages: 1. sample is destroyed
2. requires additional gases and
controllers

8. Thermal conductivity detector

9. TCD
Advantages:
1. Simplicity
2. Response to both organic & inorganic species
3. Non destructive character
Disadvantages:
1. Low sensitivity

10. Electron capture Detector

11. ECD
Advantages:
• Selective in response
• Halogens, peroxides, quinones & nitro groups are
detected with high sensitivity
• Detection & quantitative determination of
chlorinated insecticides.
• Highly sensitive, linear response
Disadvantages:
• Insensitive to groups like amines, alcohols and
hydrocarbons

12. Thermionic detectors

13. TID
• Selective towards organic compounds
containing phosphorous and nitrogen
• Response to phosphorous is 10 times greater
than nitrogen atom
• TID is 500 times more sensitive to
phosphorous containing compounds and 50
times more sensitive to nitrogen containing
compounds when compares with FID

14. Electrolytic conductivity detector

15. Electrolytic conductivity detector
• Halogen sulphur and nitrogen containing
compounds are analyzed in ECD
• Reaction tube is made of nickel kept at
temperature of 850-1000 ⁰C
• Products are dissolved in conductive solution

16. Photo ionization detector

17. PID
• Eluent is photoionised by UV radiation from
10.2eV hydrogen or 11.7eV argon lamp.
• More sensitive for aromatic hydrocarbons and
organophosphorous compounds which are
easily photionized

18. Atomic Emission detectors

19. AED
• Effluent is introduced into microwave induced
plasma
• Plasma atomizes all elements in sample
• Atomized elements excite to give
characteristic atomic emission spectra

20. Flame photometric detectors

21. FPD
• Analysis of air water pollutants & pesticides
• Selective to phosphorous and sulphur
• P is converted into HPO which emits bands at
about 510 and 526nm
• S is converted to S2 which emits the band at
394nm

22. GC-MS

23. GC-IR