I wanted to make potassium chloride and all I had was potassium sulfate fertilizer (I guess) so I thought I can mix K2SO4 and CaCO3 in water and add
hcl to make CaCl2 in situ which should react immediately with potassium sulfate to make potassium chloride and calcium sulfate right?
I added concentrated potassium sulfate solution to eggshells but it started reacting and releasing a GAS!
I did the reaction in PET water bottle and I took it outside cause I freaked out
WHAT HAPPENED?Fyndium - 26-11-2020 at 08:10
Are you sure the stuff you've got are pure? Even if they contained traces of acids, the carbonate could react.
The solubility of calcium carbonate is exceedingly low, two orders lower than CaSO4 so eventually they should react, yes, but how long it takes and
what conditions, is another issue. It would also be difficult to determine when the reaction is complete.unionised - 26-11-2020 at 09:34
Eggshells are remarkably porous. It's possible that most of the gas you saw was air.
It would be more efficient to dissolve the eggshells in HCl
then add the solution of K2SO4 to the CaCl2 solution.
That way you avoid the problem of CaSO4 "coating" the shells.
You still have a potential problem; the CaSO4 is likely to precipitate as a sticky mess which is hard to filter off.
rockyit98 - 26-11-2020 at 09:47
potassium chloride is a common fertilizer called "muriate of potash" i got lots of it for cheap but need filtering and recrystallization.
may be try NaCl + K2SO4 and cool it Na2SO4 have low solubility at lower temperatures.
[Edited on 26-11-2020 by rockyit98]Piroz - 5-1-2021 at 18:11
Some dessicants are good sources of CaCl2, I used that for making potassium chloride from wood ashes.
You still have a potential problem; the CaSO4 is likely to precipitate as a sticky mess which is hard to filter off.
It's not problem if solution is diluted, in diluted solution CaSO4 doesn't precipitate quickly, but forms tiny crystals. If the reaction occurs in
plastic bottle crystals will grow on the wall, leaving clear solution after few days.
