inlet pressure

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wildroseGC's picture
inlet pressure

      i use 5890A GC splitness FID. My column is about 3 months old, after doing maintanence, the first peak C10 is on the solvent peak. We low down the inlet pressur from about 7psi to 5psi, then there is a little space between C10 and solvent peak. My question is decreasing inlet pressure will affect the separation peak or peak area? i think we should change the new column, cause the column is short to separate compound
     thank you

Dr. Analytical
Dr. Analytical's picture
Please give us more

Please give us more information about the column: type, dimensions, carrier gas, GC oven conditions.

Changing the pressure will change the flow rate of carrier through the column.  Usually this will not create a large change unless you are operating outside the normal flows for your column.  

Did this change happen immediately after maintenance?  What maintenance was performed?  Maybe the column was not installed correctly.

wildroseGC's picture
thank you so much Dr

thank you so much Dr.Analytical. The Column is DB1. This happened after using the column for some time, i think because when we changed the gold seal, trim the column then made the column getting shorter and shorter. Finally the column cann't separate the solvent peak and C10. After i install the new column, everything is good. I just wonder that will affect the peak area. This change only my manager or supervisor could do, for me i prefer change the column
       thank you again. i really like this website for people to discuss the questions