Sunday, 30 December 2018

Gas chromatography . ppt

Gas Chromatography
What is Gas Chromatography? <ul><li>It is also known as… </li></ul><ul><ul><li>Gas-Liquid Chromatography (GLC) </li></ul><...
GAS CHROMATOGRAPHY <ul><li>Separation of gaseous & volatile substances </li></ul><ul><li>Simple & efficient in regard to s...
<ul><li>Sample to be separated is converted into vapour </li></ul><ul><li>And mixed with gaseous M.P </li></ul><ul><li>Co...

What is Gas Chromatography? <ul><li>The father of modern gas chromatography is Nobel Prize winner John Porter Martin , wh...
 
The Next Generation in Gas Chromatography

How a Gas Chromatography Machine Works <ul><ul><li>First, a vaporized sample is injected onto the chromatographic column...
Chromatographic Separation <ul><ul><li>Deals with both the stationary phase and the mobile phase . </li></ul></ul><ul>...

Chromatographic Separation <ul><li>Chromatographic Separation </li></ul><ul><ul><li>In the mobile phase, components of the...

Chromatographic Separation (continued) <ul><ul><li>The peaks can then be read and analyzed by a forensic scientist to dete...

Chromatographic Analysis <ul><ul><li>The number of components in a sample is determined by the number of peaks. </li></ul>...
Peaks and Data
 

 
 
 

 
PRACTICAL REQUIREMENTS <ul><li>Carrier gas </li></ul><ul><li>Flow regulators & Flow meters </li></ul><ul><li>Injection dev...
CARRIER GAS <ul><li>» Hydrogen </li></ul><ul><li>better thermal conductivity </li></ul><ul><li>disadvantage: it reacts ...

Requirements of a carrier gas <ul><li>Inertness </li></ul><ul><li>Suitable for the detector </li></ul><ul><li>High purity ...

Flow regulators & Flow meters <ul><li>deliver the gas with uniform pressure/flow </li></ul><ul><li>rate </li></ul><ul><li>...
 
Soap Bubble Meter <ul><li>â—Š Similar to Rota meter & instead of a float, soap bubble formed indicates the flow rate </li>...
Injection Devices <ul><li>Gases can be introduced into the column by valve devices </li></ul><ul><li>liquids can be inject...

COLUMNS <ul><li>Important part of GC </li></ul><ul><li>Made up of glass or stainless steel </li></ul><ul><li>Glass column-...
<ul><li>Depending on its nature </li></ul><ul><li>1.Packed column: columns are available in a packed manner </li></ul><u...
3.SCOT columns (Support coated open tubular column <ul><li>Improved version of Golay / Capillary columns, have small samp...
Columns <ul><li>Packed </li></ul><ul><li>Capillary </li></ul>

 

 

Equilibration of the column <ul><li>Before introduction of the sample </li></ul><ul><li>Column is attached to instrument &...
Temperature Control Devices <ul><li>Preheaters : convert sample into its vapour form, present along with injecting device...
Temperature Control <ul><li>Isothermal </li></ul><ul><li>Gradient </li></ul>Instrumentation - Oven

DETECTORS <ul><li>Heart of the apparatus </li></ul><ul><li>The requirements of an ideal detector are- </li></ul><ul><li>Ap...

1.Thermal Conductivity Detector (Katharometer, Hot Wire Detector) Measures the changes of thermal conductivity due to the ...
Thermal Conductivity Basics When the carrier gas is contaminated by sample , the cooling effect of the gas changes. The d...
When a separated compound elutes from the column , the thermal conductivity of the mixture of carrier gas and compound gas...
<ul><li>􀁺 Measures heat loss from a hot filament – </li></ul><ul><li>􀁺 filament heated to const T </li></ul><ul><li>whe...

 



Relative Thermal Conductivity 0.17 Nitrogen 0.13 Methanol 1.00 Helium 0.12 Argon Relative Thermal Conductivity Compound 1....

Advantages of Katharometer <ul><li>Linearity is good </li></ul><ul><li>Applicable to most compounds </li></ul><ul><li>Non ...

Flame Ionization Detector <ul><li>Destructive detector </li></ul><ul><li>The effluent from the column is mixed with H & ai...
<ul><li>FIDs are mass sensitive rather than conc. sensitive </li></ul><ul><li>ADVANTAGES: </li></ul><ul><li>µg quantities ...

FID
 


























































































































































































































































































Posted by on

1 comment:

  1. Steven Cohen17 January 2022 at 04:43

    Ecdp stock Overview: Stay ahead of the market with our live and real time stock market overview. Get all of your favorite stocks in one place, and get alerted to live news at the same time!

    ReplyDelete

Subscribe to: Post Comments (Atom)