Method of Base Deactivation of Inlet Liners?
Posted: Mon Oct 06, 2008 4:38 pm
by ismellgas
After leaching, to remove metal oxides, what chemical agent and derivatization method should I use to deactivate the surface silanols?
Posted: Mon Oct 06, 2008 7:05 pm
by JGK
Fluka produce a variety of silanizing reagents for GC, for example
http://www.sigmaaldrich.com/catalog/sea ... LUKA/85433
Posted: Mon Oct 06, 2008 7:50 pm
by sassman
First you should clean the liner with detergent solution, then methanol, then water, then soak in 25% HCl overnight, then rinse with water and dry in an oven. Assuming that you have already done that, you can try this:
Solution Preparation:
5% DMDCS SOLUTION IN METHYLENE CHLORIDE
Using a 100ml graduate, add 50mls of methylene chloride, mix this with 5 milliliters
of DMDCS, Mix, then add 45 mls to fill to the 100 ml mark.
Make this solution on a daily basis.
All glassware in contact with this solution should be dried thoroughly.
Deactivating Procedure:
[1] Immerse all items to be deactivated into the 5% DMDCS solution for a period of 5 to 30
minutes (average time about 15 minutes).
[2] Pour off deactivating solution and immediately rinse with methylene chloride.
Proceed immediately to the next step as to minimize the exposure to room moisture.
[3] Cover pieces with methanol for a period of 15 to 30 minutes.
[4] Drain off all of the methanol and blow dry using nitrogen.
glass wool and silica beads are placed on pyrex plates and are dried at 70oC in an
oven until completely dry.
... Or just buy a new liner.