04-14-02 19:00
No 296835
Can powdered KOH bee dehydrated to remove the atmospheric water it picked up while being powdered simply by heating in an oven @175C, or would this drastically increase K2CO3 content?
Many thanks,
Azarius
(Hive Bee)
04-14-02 19:14
No 296838
It's posible to dehydrate KOH in an owen (dont' let it melt)
It will pick some CO2 up from the air, but not that much (there is only 200-300ppm to take)
(Hive Addict)
04-14-02 19:25
No 296839
KOH.(H2O)x
x=4 MP -32.7°C
x=2 MP 35.5°C
x=1.5 and 1 MP 143°C
(Pickering, J.C.S., 1893, 63, 890)
At about 200°C I can't really see much more than small amounts of Carbonate forming.
If you are really bothered by small amounts of carbonate, heat the KOH in an inert atmosphere/vacuum, or heat the KOH higher than 1000°C to rid the CO2
Nobodys home
(Old P2P Cook)
04-14-02 20:08
No 296850
Can powdered KOH bee dehydrated to remove the atmospheric water it picked up while being powdered
But if the powdered KOH is being used to isomerize an allylbenzene then is this necessary?
(Hive Bee)
04-14-02 23:00
No 296897
Terbium, aurelius wasn't sure if that was retorical. So... no, it doesn't need to be dried. it is preferred that no visible water is present, but the minute traces make almost no difference in the course/yeild of the isomerization. (from practical experience)
(Stranger)
04-15-02 01:47
No 296950
k, thanx ppl :)