column bleeding

HI abdel_elh,

this is by far too little information to give you an answer. Please describe your analysis, which column do you use, your parameters?

Regards,

Norbert

dear,

we use three types of different columns (molsieve 5A, HP-AL/s, HayesepQ).

kind regards, 

Hi, this is still not sufficient.

I assume you use a column switching system with HayeQ as first column, switching the first eluting peak to M5A for the permanent gases, and backflush the HayeQ to Alox for hydrocarbon analyses?

• How many detectors do you use?
• When do you see the "bleeding"? Is it a raise of the baseline?
• Are retention times stable? Is there a shift to higher or lower times?
• Have the peak width changed?

Molsieve and aluminium oxide are inorganic compounds and normally cannot bleed, HayeQ might be bleeding if the temperature was above 250 °C.

As you are in Belgium I suggest calling your nearest Agilent office and connect to the CSD Technical Support team as this is no simple question.

Regards,

Norbert