Chromatography Forum

What type of stationery phase could be most interaction with benzene? I want to analysis some impurities in benzene by internal standard method. I planned connect to column together which first column retain benzene while my desired impurities (mostly light dienes) pass without retain. After that I can use second column to separate desired impurities. By this way benzene peak will be appeared near end of chromatogram.
Now, I am looking for column which has most interaction with benzene. I tried CP-wax column as polar phase but it can not be able to shift benzene peak enough.
Would you please suggest another type.

The TCEP phase column is a traditional favorite, it shifts benzene a carbon number later !0.5 than the Wax (9.5) phase.

There is a new phase sold by Supelco that has only been on the market one or two years which is reported to shift benzene another carbon number (11.5).

It is the only new development that improves performance over the TCEP in the last 50 years !

best wishes,

Rod

Use old good phenyl based columns (similar with similar is the rule).
Use good brand, use longer, narrower and higher film thickness, at least 1 or may be even 3 um film. The ultimate solution will be GCGC, but 100m column is definitely cheaper than GCxGC.

Alexandre

mr3573 wrote:

"I want to analysis some impurities in benzene by internal standard method. I planned connect to column together which first column retain benzene while my desired impurities (mostly light dienes) pass without retain. "

He wants to separate alkanes and mono- and di- enes from the aromatic benzene. Your suggestion would be an exercise in futility to accomplish his goal.

One of the new ionic liquids will perform the separation he desires while he can then use a second column, usually a boiling point column to separate and identify the impurity components.

Traditionally the TCEP phase was used to perform the first separation.

best wishes,

Rod