Gas Chromatography (GC), is a type of chromatography technique which is used to separate mixtures of chemicals into individual volatile organic components (VOCs) (Carlin and Dean, 2013). In summary, the separation takes place when the sample mixture is injected into the GC inlet by using a syringe where it is vaporized and swept through the capillary column by a stream of carrier gas, which called the mobile phase. The carrier gas carries the sample mixture through stationary phase what is referred to a chemical that can attract components in a sample mixture selectively which are packed in a column. Each compound in the mixture interacts with the stationary phase at various rates. This means those will first elute from the column, are interact
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The oven is operated in two modes which are isothermal and temperature-programmed. In isothermal operating mode, the oven is kept at the same and constant temperature that is set by the scientist during running the analysis. This method is suitable if a fairly simple sample is being analysed. In addition, the retention of compounds is more dependent on the column length such that a doubling of column length will double the analysis time. However, for more complex mixture of analytes, temperature-programmed mode is recommended in which the temperature of the column oven is programmed to increase gradually throughout the whole analysis. Moreover, the retention is more dependent on temperature such that doubling the column length marginally increases analysis time (Carlin and Dean, …show more content…
It is consists of an air/hydrogen flame to pyrolyse effluent sample of a GC column following produced ions including cations and electrons. A voltage is applied across the flame and the resulting flow of the charged species which is detected as an electric current. An electrode is measured this current flow, then recorded as a chromatogram (Carlin and Dean, 2013). The current flow produced can be provided some information about the sample, due to it is different from the signal produced by the carrier gas and the fuel gas (Shellie,
The oven is operated in two modes which are isothermal and temperature-programmed. In isothermal operating mode, the oven is kept at the same and constant temperature that is set by the scientist during running the analysis. This method is suitable if a fairly simple sample is being analysed. In addition, the retention of compounds is more dependent on the column length such that a doubling of column length will double the analysis time. However, for more complex mixture of analytes, temperature-programmed mode is recommended in which the temperature of the column oven is programmed to increase gradually throughout the whole analysis. Moreover, the retention is more dependent on temperature such that doubling the column length marginally increases analysis time (Carlin and Dean, …show more content…
It is consists of an air/hydrogen flame to pyrolyse effluent sample of a GC column following produced ions including cations and electrons. A voltage is applied across the flame and the resulting flow of the charged species which is detected as an electric current. An electrode is measured this current flow, then recorded as a chromatogram (Carlin and Dean, 2013). The current flow produced can be provided some information about the sample, due to it is different from the signal produced by the carrier gas and the fuel gas (Shellie,