GAS CHROMOTOGRAPHY OF KNOWN AND UNKNOWN MIXTURES JULY, 12 2013 ORGANIC CHEMISTRY 2 SUMMERS 2013
Purpose
The purpose of this laboratory is to determine the composition of unknown liquid mixture with the use of Gas Chromatography.
Introduction
The Gas Chromatography is a physical method of separation of unknown liquid mixtures. Gas chromatography is actually used for covering large variety of organic compounds. The basic requirement is the sample should be volatile, and it should not be decomposed in the vaporization process. Because the vaporization happens in an inert atmosphere, but the decomposition of the sample is usually not a problem.
Gas chromatography normally consists of the following;
A sample port or injector or introduction and vaporization of the sample
A carrier gas normally nitrogen or helium to carry the sample to the column
A separation column consists of metal tubing packed with solid materials coated with absorbing liquid.
The flow equipment is to maintain constant flow of carrier gas through the column
The detector for measuring the quantity of separated components
A temperature control column
Procedure
The unknown material F was selected as 0.2 ml was carefully aspirated into a Hamilton syringe, before the aspiration of the mixture, Acetone was used to clean the Hamilton syringe. The start button on venire software and enter initial settings. The following are initial settings;
Initial temperature = 30 C
Ramp speed = 10 C/min
Carrier gas partial pressure = 4.0 kpa (This is about 4% of atmospheric)
Hold time was 0 for initial conditions an 2 min for maximum temperature
Final temperature of 150 C
