8890 gas identification

Hello,

1. Check your method and configuration. Column configuration like lenght and diameter should correspond to what is really installed.

2. Try to increase inlet pressure. Sometimes low pressure gives such kind of problems.

Kind regards,
Rustam

Hello,

1. Check your method and configuration. Column configuration like lenght and diameter should correspond to what is really installed.

2. Try to increase inlet pressure. Sometimes low pressure gives such kind of problems.

Kind regards,
Rustam

I did verify that the column dimensions were correct. We had a 30 m x 0.53 mm, 3 um column installed.

Hello smthro06 

If the column dimensions were correct, then there are two points I would check:

1) What gas has been used before. In my case I have two gas filters (O2 and H20)  and if I switch between Nitrogen and Helium then I need to wait until previous gas is swept from the gas filters. I just use method with bigger spilt ratios and after 30-40 minutes with corresponding to column dimensions flow rate and split from 50:1 to 100:1 I can sweep previous used gas.

2) Try to increase inlet pressure. Sometimes low pressure gives errors for gas identification.

Kind regards,
Rustam

Thanks for those points.

I just completed the installation of the valve and plumbing to allow for gas changes. The GCMS combination filter will be coming soon and there are no other absorbers in line until that arrives so option 2 is more likely. The method being performed at the time was a splitless procedure through a 0.53 mm ID column. Even at 10 mL/minute, the head pressure is always pretty low. I will repeat the gas check when a smaller ID column is being used.