Moisture measurement in hydrocarbons

[alamontagne]

Hi. I was ask to measure moisture down to 8 ppb with a GC in a background of methane and propane. What is the most suitable packed column(s) to do that application? I'm using a plasma detector in helium of argon carrier gas.

[larkl]

I'd use a wax (polyethylene glycol) column, but that wouldn't be packed. You could use a megabore capillary if your GC has a packed column inlet.

[chromatographer1]

Try a 1% PEG phase on Carbopack B in a fused silica coated SS or glass column.

OR, a Hayesep or Porapak R in FSOT SS or glass column.

There are moisture analyzers dedicated to your analysis that are not that expensive if that is an option, especially if your analysis is a temporary one, you might rent a unit.

Good luck,

Rodney George
consultant