From development to application of an optimized gas chromatography analysis for C3-C10 hydrocarbons.

[Display omitted] • A new method of C3-C10 analysis was developed by Box-Behnken DoE & multivariable optimization. • The effects of 11 GC input factors on the retention time, peak resolution and height were studied. • Analysis of variance was used to determine the significant variables of GC method. • The new method outperformed an industrial method in terms of resolutions and the retention time. Reducing the Gas Chromatography (GC) run time, and improving the resolution with appropriate peak heights in GC methods are indeed vital goals for any analysis labs. This research was focused on improving an existing empirical method for C3-C10 hydrocarbon analysis in a specific petrochemical complex with many samples per day. The hydrocarbon standards used for calibration were 0.5 W/W% Benzene and 0.5 W/W% 1-Methyl-Cyclopentene, as well as 2 W/W% m-Xylene and 2 W/W% p-Xylene. Moreover, Box-Behnken Design was used to identify the common significant variables between 11 quantitative input factors affecting the retention time, peak resolution and height for each pair. After performing 182 experimental analyses, carrier gas flow rate, initial temperature hold time, oven programming (ramp 1) and oven initial temperature were identified as the common significant variables. The results were used to optimize the method which could increase the resolutions by 50% and 40%, and simultaneously decrease the retention time by 34.2% and 28.3% for both pairs respectively. [ABSTRACT FROM AUTHOR]