Importance of quality control in a gas chromatographic method to characterize crude oils

Abstract

SummaryA quality control scheme has been developed to achieve reproducible capillary GC characterization of crude oils and petroleum condensates. The method uses an internal standard to quantify the amount of non-eluted material in the crude oil sample. Correlation between the gas chromatographic results and actual distillation was 2 %. After repeated use, however, weekly analysis of the same standard crude oil did not give the correct composition. This was a result of discrimination, which worsened with time, as a result of leaks in the septum or the graphite ferrules. More reproducible results were obtained by performing frequent analyses of quality control samples to ensure that the gas chromatographic system was operating properly. The use of quality control charts was a convenient way of ensuring correct operation and identifying the need for corrective action on the gas chromatographic system.

Partial least squares modeling of retention data of oxo compounds in gas chromatography

“…On this column carbonyl and nitro groups are retained more strongly than alcohols and esters, i.e. DB-210 has the unique property of retaining carbonyl groups more strongly than the hydroxyl group [28,29].…”