Tetrahydrofuran x RP Columns

[carlos.teixeira]

Hi Folks,

The method below has produced constant overpressure after 8h to 14h of pump flow (analysis). The pressure starts with 170 kgf/cm2 but always the chromatograph stop before the end of the analysis,since the max. pressure is 400 kgf/cm2.

1) Do you have any ideia about the cause?

2) Is it common any THF generate column pore swelling?

Chromatographic method
Mobile phase composition: MeOH = 90%, THF = 5%, Water = ¨5%
Flow rate: 1.5 mL/min
Temperature: 25 degree Celsius
Column: C-18 Zorbax 250mm 4.6mm 5um

Thanks,

[Consumer Products Guy]

We've used THF for years with RP-18 columns, and not had any such issues. If you haven't already, run the sequence but WITHOUT actual injections for your 8 to 14 hour timeframe, and see if the pressure still goes up like you stated. And post what you find.

[carlos.teixeira]

Sorry for my delay... we just changed THF for ACN and problem was resolved.

Wonderful elutions for everybody!!