The Vespiary

The Hive => Chemistry Discourse => Topic started by: FriendlyFinger on May 01, 2003, 07:21:00 AM

Title: Will Molecular sieves scratch?
Post by: FriendlyFinger on May 01, 2003, 07:21:00 AM
Hi there,

I want to use 4A molecular sieves with 3N KOH/BuOH + Allylbenzene at room temp stirring for 3 hours. Will this scratch the fuck out of my shinny flask.

Regards,
FF.
Title: Powder
Post by: hest on May 01, 2003, 10:25:00 AM
Nope, but your sives will bee a fine powder after 3 houers of stirring. Might want to use shaking instead ?
Title: What was I thinking. I should just dry the...
Post by: FriendlyFinger on May 02, 2003, 04:24:00 AM
What was I thinking. I should just dry the BuOH and the allyl separately with the sieve and the KOH in the oven before mixing together.

I plan to use 4A  small beads for the Allyl and 3A for the BuOH, but here is where I'm a bit confused. In J.Org. Soc. (Don't have the reference here) they talk about powered 3A as the dissicant of choice under the heading of "Butanols" but refere specifically to 2-Butanol and tert-butanol. Would I be right in assuming that powered 3A would be the better choice for n-BuOH.

The reference suggests that the reason the powder is better than the beads and why the butanols take longer to dry is because of their increased viscosity compared with say ethanol.

Thanks,
FF
Title: sives
Post by: hest on May 02, 2003, 11:38:00 AM
Nuke the sives in the micro. stup before they melt (the doo). Then let them cool in a decikator. Dump the now cold and dry sives in your solvent. waith 48 houers, shake from time to time. You now have abs. dry solvent's.
Title: WARNING!
Post by: ClearLight on May 03, 2003, 01:36:00 AM
First use of molecular sieves in a dehydration process is an Exothermic reaction!  After they have been "conditioned" there is no heat release...

Title: Test of sives
Post by: hest on May 03, 2003, 05:27:00 PM
Yes, the best test for sives 'drynes' is to pu a drop off wather into your hand, and then place a sive into the drop. Iff it burn's they a good. (the tuff one's just 'kiss' the sives, iff they burn your lip's they are dry)
Title: Won't 3N KOH breakdown molecular sieves?
Post by: foxy2 on May 05, 2003, 03:32:00 AM
Won't 3N KOH breakdown molecular sieves?
Maybe I'm mistaken.
Title: i dont think it will scratch...
Post by: bones on May 07, 2003, 03:17:00 AM
i dont think it will scratch... not that scratching really all that much of a problem anyway... but if your worried.. perhaps use an alternative to your shiny rb flash.... mabey a jar will be ok??
Title: Guess I was wrong, should bee ok in KOH
Post by: foxy2 on May 07, 2003, 04:16:00 AM
Guess I was wrong, should bee ok in KOH