a type of chromatography usually used to analyze pollution aspects.

1. GAS LIQUID
CHROMATOGRAPHY
By
Anand Narayanan D
FEN-2018-33-01

2. CHROMATOGRAPHY
• Chromatography is an analytical technique where in a
sample mixture under test is separated into different
components based on difference in their affinity for a
stationery phase and mobile phase.

5. GAS LIQUID
CHROMATOGRAPHY(GLC)
• In GLC the mobile phase is an unreactive gas , such as
nitrogen(Carrier gas).
• The stationery phase is a non
volatile liquid held on a finely
divided inert solid support.

6. PRINCIPLE
• Gas liquid chromatography runs on the principle of partition.
• In GLC , components of the gaseous samples are separated due
to partition between a gaseous mobile phase and a liquid
stationery phase held in a column.

9. The mobile phase
• An inert gas such as He or N2
-Function is to transport sample vapours through columns.
-No chemical interaction with sample.
• Typical parameters
-column inlet pressure : 10-50psi
-flow rate 25-50mL/min
• Precise control of carrier gas flow rate is crtical to obtain
reproducible retention times.

10. Sample injection
 Sample is injected using a syringe into a hot carrier gas(mobile
gas)
-High temperature( at least 50 ͦC above B.P of sample)
causes vaporization of sample.
- introduced a narrow plug of sample vapour onto the
column.
 Various designs
-for packed columns , inject 1 to 5 microliters of sample.
-for capillary columns , a split valve is used to introduce a
small fraction sample into the column .

17. Detectors
• Generate an electrical signal proportional tp solute concentration
or mass flow rate.
Ideal characteristics :
• High sensitivity
• Rapid response time
• Applicable to wide range of samples
• Easy to use
• Stable & predictable response

26. RECORDER
• Recorder is device that draws the chromatogram that results
from a chromatographic process on to chart paper.
• The time scale of the chart movement normally ranges from
about 1cm/ second to 1cm / hour

27. Advantages of GLC
• Both qualitative and quantitative analysis are possible.
• Instrument is simple , time of analysis is short.
• High sensitivity
• This method is applicable for 60% of organic compounds
• Very small sample sizes can be used
• Analysis can be highly accurate and precise.

28. FACTORS AFFECTING SEPERATION
• Particle size and surface area
• Carrier gas flow rate
• Type and amount of stationery phase
• Column length
• Column diameter
• Column temperature

29. CONCLUSION
• Gas chromatography (GC) is a common type of
chromatography used in analytical chemistry for
separating and analyzing compounds that can be vaporized
without decomposition.
• The sample being measured is injected into the carrier gas
using a syringe and instantly vaporizes (turns into gas
form).
• The gases that make up the sample separate out as they
move along the column which contains the stationary
phase

30. REFERENCES
• Introduction and principle of GLC , by Dr.Vishnu Vrardhan
Reddy Pulimi , www.slideshare.net
• Gas liquid chromatography by Srinivas Nandyala ,
m.athorstream.com