any one kno how to make potassium carbonate?

[akcapr]

Does anyone know how i could synthesize some potassium carbonate?

[akcapr]

will exposing KOH to CO2 do the trick?

[H2SO4]

i think K will hold onto OH pretty tightly, maybe a double replacement with sodium carbonate will work

[YT2095]

burn a whole pile of wood and collect the ash, mix with water then filter the liquid off, that will be potassium carbonate and hydroxide, bubble excess CO2 through this to convert the rest to your carbonate

[jdurg]

KOH and CO2 will only give potassium bicarbonate. That hydrogen atom won't just dissapear.

[budullewraagh]

well...

KOH+CO2-->KHCO3

KOH+KHCO3-->K2CO3+H2O

[H2SO4]

or you could take the hydrogencarbonate and maybe decompose it to carbonate by heating it. It works with sodium bicarbonate, why not potassium bicarbonate.

[akcapr]

xcept i dont hav any potassium bicarbonate

[akcapr]

that will be potassium carbonate and hydroxide, bubble excess CO2 through this to convert the rest to your carbonate

 

does thius mean KOH will become potassium carbonate wen i bubble CO2 through it, or the co2 will just nutralize the potasssium hydroxide?

[budullewraagh]

you'll have an alkaline solution of KHCO3

[YT2095]

KOH and CO2 will only give potassium bicarbonate. That hydrogen atom won't just dissapear.

 

good point, I neglected to mention that you should crystalise it and heat it to 373k or above before you lose that Hydrogen and it gets replaced by K.

 

Ooops, sloppy of me!

[akcapr]

so i can make potassium carbonate like this: bubble co2 through KOH, dry it, and heat it, and i will have potassium carbonate. But i also could make it with the burning method like so: burn some wood, mix with water and filter, bubble co2, dry, and heat.

[budullewraagh]

or you could just use conc KOH and do it stoichiometrically in a 2:1 ratio of KOH to CO2

[akcapr]

i have fogoten much about stoichiometry. Can someone reminds me how i would go about figuring out how much co2 and koh id nee stoichiometrically? thx

[budullewraagh]

well, first may i ask how you are going to produce the CO2?

[YT2095]

LOL, he`ll probably add vinigar to potassium Carbonate )

 

I use the 12.5g CO2 cartridges with a regulator fitted and then bubble that through an air stone (as used in fish tanks).

[H2SO4]

just hook an airstone up to a flask with some sodium bicarbonate vinegar or dilute H2SO4 for a longer lasting reaction. This should give you sufficient CO2

[Primarygun]

Is it,

Adding little CO2 into KOH---> Potassium carbonate+ water.

Adding excess CO2 into KOH---> Potassium hydrogencarbonate ?

[akcapr]

actually, i find it easyies to heat/decompase chalk to calcium oxide

[YT2095]

actually, i find it easyies to heat/decompase chalk to calcium oxide

 

and that has WHAT to do with this thread?

 

Primarygun, it`s best to add the excess CO2 and decompose the crystals afterwards, that way your yeild is high and there`s no messing about with guess work

[akcapr]

i tried the ash method. Out of like 15 pounds of wood i got however much ash, which in turn gave me like a gram of potassium carbonate or bicarbonate- watever it was .It stunk like hell nad wasted alot of my time. At least i know to just buy it next time. ( old/ancient methods dont seem to work well enough for me)

[H2SO4]

ya, ancient methods never work. I didnt know potassium carboante could decompose to calcium oxide. ill have to try it.

[akcapr]

ugghhh... wat are u talking about...potassium carbonate will decompose to KOH not CaOH

[BenSon]

ya, ancient methods never work. I didnt know potassium carboante could decompose to calcium oxide. ill have to try it.

 

K2CO3 = CaO

 

Think about what your saying here...

 

~Scott

[YT2095]

a gram of crystal from 15 pounds of wood is a little low, but not bad.

what were you expecting? it was Free wasn`t it, and hopefully you learned something, so stop complaining.