Sciencemadness Discussion Board
Not logged in [Login ]
Search the forums Search   Frequently Asked Questions FAQ   View member list Member List   Today's Posts Today's Posts   Forum Stats Stats Back to: sciencemadness.org
Sciencemadness Discussion Board » Fundamentals » Chemistry in General » NaNO3 to KNO3 and purify it Go To Bottom

Printable Version  
Author: Subject: NaNO3 to KNO3 and purify it
vudiemphuongchi
Harmless
*



Posts: 2
Registered: 20-4-2019
Member Is Offline


[*] posted on 20-4-2019 at 17:56
NaNO3 to KNO3 and purify it

Hello everyone. I want to make a question that is intriguing me for a while.
So. I bought a pack of saltpeter but it has two components in it: sodium nitrate and potassium nitrate. I suspect that might be a 50:50 mixture or 65:35 based on some data sheets i found in the internet. But I'm not really sure. Ok, so this is the thing, i'm only interested in the potassium nitrate and i want to convert the remaining sodium nitrate in the mix to KNO3 too, but i'm not sure if my plan is gonna work so i want your opinion.
So, i plan to dissolve all the nitrate in hot water and mix potassium chloride and try to precipitate the KNO3 out by cooling the solution in the freezer and then filtrating out the KNO3 crystals. But I'm not sure if that is gonna work since i heard that this double displacement reaction can't occur according to some forums. But I'm not 100% convinced of it.
So, what you guys sugest? I'm not a chemistry expert and don't have access to all chemicals i might need. So i want some suggestion for something i can do at home with no fancy glassware or inaccessible chemicals.
I know i can buy pure KNO3 but i'm not willing to and i'm interested in using this that i already have. But anyways. Thank for any answers and your time.
View user's profile View All Posts By User
clearly_not_atara
International Hazard
*****



Posts: 2787
Registered: 3-11-2013
Member Is Offline

Mood: Big

[*] posted on 20-4-2019 at 20:58


The solubility of potassium chloride is not very high. I suggest using a more soluble potassium salt such as K2CO3, or, since that might precipitate some Na2CO3, KOAc.



Quote: Originally posted by bnull  
you can always buy new equipment but can't buy new fingers.
View user's profile View All Posts By User
Bedlasky
International Hazard
*****



Posts: 1239
Registered: 15-4-2019
Location: Period 5, group 6
Member Is Offline

Mood: Volatile

[*] posted on 20-4-2019 at 21:08


Hi.

In my opinion it should work. Solubility (at 0°C) of KNO3 is 133 g/l, NaNO3 730 g/l and KCl 280 g/l. Solubilities will be different of cource because NaNO3 will decrease solubility of KNO3 (and conversly). If you added some KCl to saturated solution of your KNO3/NaNO3, some KNO3 will be precipitate. After filtration you can use fractional crystalization and separate some KNO3 from solution.

[Edited on 21-4-2019 by Bedlasky]
View user's profile View All Posts By User
j_sum1
Administrator
 Thread Split
13-5-2019 at 02:31

 Sciencemadness Discussion Board » Fundamentals » Chemistry in General » NaNO3 to KNO3 and purify it   Go To Top