Sciencemadness Discussion Board

Basic Potassium

raiden - 6-2-2008 at 03:21

Hello. Posting from my phone because my computer is dead. I am looking for a synthesis for both Potassium Hydroxide and the carbonate. I plan on making some Benzoic Acid from Sodium Benzoate and HCl and then neutralising this with Copper Hydroxide synthed from Copper Sulfate and Potassium Hydroxide. I realise that I could just use the Copper Carbonate but the OH would also help me when I am destroying Chlorate in my cells and don't want Na in there. Is there an easy way to make this? No places sell it OTC in australia as far as I know. Also, will I get good purity Benzoic acid from just the sodium salt or should I run it back through the potassium hydroxide/CO3?

[Edited on 6-2-2008 by raiden]

microcosmicus - 6-2-2008 at 09:19

Quote:
Originally posted by raiden
I am looking for a synthesis for both Potassium Hydroxide and the carbonate.
[Edited on 6-2-2008 by raiden]


If you like the old ways, you might want to burn some wood to white ash
and extract with water. That's how the element got its name --- "pot-ash-ium".

Since you mention an electrolytic cell cell in your post, a more modern
approach is to get some KCl (often sold as "salt substitute" for people
who want to avoid sodium in their diet) and electrolyze it, taking care to
keep the KOH from mixing with the Cl2 to produce KOCl --- use a narrow
tube between electrode compartments, diagphram, porous ceramic cup,
salt bridge, or some such hack. By mixing CO2 into your KOH, you can
then produce KHCO3 and K2CO3.

[Edited on 6-2-2008 by microcosmicus]

YT2095 - 6-2-2008 at 09:41

if you DO go the wood ash route, then be sure to stir in some garden lime (calcium hydroxide) this will leave you with your KOH ;)

and what ever you want as the carbonate just leave in the bucket or plastic basin to dry and crystalise naturally.