column bleeding

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

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