Analytical method validation of GC-FID for the simultaneous measurement of hydrocarbons (C2-C4) in their gas mixture

An accurate gas chromatography coupled to a flame ionization detector (GC-FID) method was validated for the simultaneous analysis of light hydrocarbons (C 2 -C 4 ) in their gas mixture. The validation parameters were evaluated based on the ISO/IEC 17025 definition including method selectivity, repeatability, accuracy, linearity, limit of detection (LOD), limit of quantitation (LOQ), and ruggedness. Under the optimum analytical conditions, the analysis of gas mixture revealed that each target component was well-separated with high selectivity property. The method was also found to be precise and accurate. The method linearity was found to be high with good correlation coefficient values (R 2 ≥ 0.999) for all target components. It can be concluded that the GC-FID developed method is reliable and suitable for determination of light C 2 -C 4 hydrocarbons (including ethylene, propane, propylene, isobutane, and n-butane) in their gas mixture. The validated method has successfully been applied to the estimation of hydrocarbons light C 2 -C 4 hydrocarbons in natural gas samples, showing high performance repeatability with relative standard deviation (RSD) less than 1.0% and good selectivity with no interference from other possible components could be observed.