Qualitative and quantitative analysis of refined F–T wax on GC–MS and GC

The products with higher carbon numbers from Fischer-Tropsch (F-T) synthesis are very complex and hard to directly be analyzed on GC due to their very high boiling point. In this work, the qualitative and quantitative analytical method for refined F-T wax samples with C 7 to C 38 was established on GC–MS. All components were well separated, qualified and quantified. The analytical errors were less than ±2 % and the errors of recovery experiments were less than ±5 %. Thereafter, this method was successfully applied in GC analysis with errors less than ±0.75 % and the analytical method on GC was also built, which will provide a more convenience way in analysis of refined F-T wax samples. Based on the obtained analytical conditions and the relative calibration factors of paraffins, the qualitative and quantitative method for the cracking products from refined F-T wax was further built according to a similar method by using simulated samples with the conversion from 5 % to 80 %. The thermal cracking of F-T wax 5# was performed and the content of LAOs in liquid mixtures reached over 50 % at 650 °C. This study simplifies the previous analysis methods which can only be completed by using a variety of standard methods and provide convenience for analysis of refined F-T wax from coal-to-liquid plant.