Chromatography Forum

The problem working with this type of sample is that you have a lot of co-elutions. An alternative is calibrate the system with a n-Paraffins standard using a HP-1 column (a metal capillary column, because to bake the column from the C36+ you need a temperature higher than 400°C) using a SIMDIS system, but you will need to estimate the areas for each peak, because the baseline won't be flat in any part of the run.

Using a PONA column, probably a great part of your sample will remain in the column, even with the column bake and you will take a long time to finish the run.

For the light fraction, you will need to use the DHA technique, because the separation for light fraction (C10) is very poor in SIMDIS.

You can do D2887, slightly modified. For one, you will likely need to have the ability to cool your oven below ambient. This is referred to a cryo method. Depending on your oil, if it's been at all weathered, you won't find much below propane anyhow. That said, your tailing issues are stemming from several potential factors. One, how much sample are you injecting? Are you using a split or splitless injection? WHat sort of liner are you using? How how is your inlet? Is your ramp too slow for the higher boilers? etc.