Filtration for C3+ hydrocarbons

[isircar]

Hello,

I want to install a 60/80 Carboxen - 1000 molecular sieve column onto my GC-8A so I can separate O2, N2, H2, CO, CO2, and CH4 using a single port. However, the gas sample that I want to analyze will contain C3+ hydrocarbons and some condensed water.

1st question: Is there a way to filter the heavy hydrocarbons that will spoil the column?

2nd question: Does water spoil the column and is there a solution to this problem? We try to separate as much of the water as possible but trace quantities of condensed water may be entrained in our flow and make it to the GC.

The ideal solution to our needs would be installing a filtration device that can trap the hydrocarbons and absorb entrained water as the gas samples travel to the carboxen column. When I asked the Supelco scientist, she suggested that I post his query here. I understand that replacing the filtration material or adsorbent at regular intervals will be needed but we we don't mind doing that. The GC-8A is an old device and we do not know enough about it to make any modifications to it.

Thank you

[isircar]

Has the following hydrocarbon trapped been used by anyone previously? http://www.vici.com/matsen/t_hydro.php

Can someone comment on its efficacy and time between replacements if they have experience with the product?

Thanks

[AICMM]

isicar,

My best suggestion here is to install a pre-column that will slow down the hydrocarbons and water and allow you to backflush them to vent. It is a very common way of doing what you wish to do.

Best regards,

AICMM

[chromatographer1]

A porous polymer column, perhaps a Q or a P will perform the backflush, which will require a minimum of a six port valve and actuator, manual or automated.

Good luck,

Rod