Involatile stuff on GC
Posted: Thu Feb 14, 2008 7:53 pm
I have a student who is doing work on the oligomerization of ethylene (expecting mostly hexene) with a chromium catalyst containing an alkyl aluminium part.
One of the problems with this is that the alkyl aluminium forms aluminium oxide in contact with air - in fact this has severely clogged a syringe before. He claims that this newly-designed catalyst is highly-active and that he now only requires about 0.0001 mol/L in concentration and that this should be small enough not to matter.
We are working with 96-well plates so I am concerned that in the long run, it will in fact build up (plus, if the reaction produces higher olefins, one might end up with involatile polymers as well). We currently do not use a guard column but have glass wool within our liners. Someone suggested a liner with Chromasorb packing (apparently, he use to get some from HP) but I could not find these anywhere on the web...
On the other hand, other people routinely inject samples that probably also contain involatile catalysts - I was just concerned that the formation of aluminium oxide might be worst...
Any suggestions or opinions are appreciated.
Thanks!
Roxanne.
One of the problems with this is that the alkyl aluminium forms aluminium oxide in contact with air - in fact this has severely clogged a syringe before. He claims that this newly-designed catalyst is highly-active and that he now only requires about 0.0001 mol/L in concentration and that this should be small enough not to matter.
We are working with 96-well plates so I am concerned that in the long run, it will in fact build up (plus, if the reaction produces higher olefins, one might end up with involatile polymers as well). We currently do not use a guard column but have glass wool within our liners. Someone suggested a liner with Chromasorb packing (apparently, he use to get some from HP) but I could not find these anywhere on the web...
On the other hand, other people routinely inject samples that probably also contain involatile catalysts - I was just concerned that the formation of aluminium oxide might be worst...
Any suggestions or opinions are appreciated.
Thanks!
Roxanne.
