The potential application of the GC-TCD using column coupling method was investigated by means of comparison with the single column method for the identification of gas mixture containing 5 permanent and 6 hydrocarbon gases. The results indicate the useful of column coupling method, relative to the single column method. In addition, the flow rate of carrier gas and column temperature on the retention time of the target components have a noticeable effect. Application of the column coupling method for qualitative identification of the targeted components in natural gas samples indicate that the method can be used for routine work in the field of natural gas measurement, since the method has proven to be able to separate both hydrocarbon and permanent gas simultaneously. All the gas components that cannot be separated in the first column were well separated in the second column, which proved that column coupling method is superior to the single column separation.
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