Sciencemadness Discussion Board

Make NaHSO4 without sulfuric acid?

▒Nick▒ - 11-12-2011 at 12:32

I need to make sodium bisulfate, and I tried adding sulfuric acid to sodium hydroxide, but the reaction is quite violent. I was wondering if there was a way to make it, possibly from sodium bisulfite? I have plenty of that.

Megak - 11-12-2011 at 13:20

Bubble oxygen gas into a solution to dissolve it, and react it with the bisulfite. I wouldn't expect great yields if you're using a oxygen generator, though

hissingnoise - 11-12-2011 at 13:41

IIRC, the oxidation, by dissolved air or oxygen, of bisulphite is slow, partly because of oxygen's limited solubility.
This is quicker and more complete; NaHSO<sub>3</sub> + H<sub>2</sub>SO<sub>4</sub> ---> NaHSO<sub>4</sub> + H<sub>2</sub>O + SO<sub>2</sub>.
And you might find a use for SO<sub>2</sub>.



Megak - 11-12-2011 at 14:49

Quote: Originally posted by hissingnoise  
IIRC, the oxidation, by dissolved air or oxygen, of bisulphite is slow, partly because of oxygen's limited solubility.
This is quicker and more complete; NaHSO<sub>3</sub> + H<sub>2</sub>SO<sub>4</sub> ---> NaHSO<sub>4</sub> + H<sub>2</sub>O + SO<sub>2</sub>.
And you might find a use for SO<sub>2</sub>.




this got me curious, how would one go about finding a catalyst for the oxygen reaction?
The only things that would speed it up would be properties in Le Chatlier's principle

&#9618;Nick&#9618; - 11-12-2011 at 15:45

Quote: Originally posted by hissingnoise  
IIRC, the oxidation, by dissolved air or oxygen, of bisulphite is slow, partly because of oxygen's limited solubility.
This is quicker and more complete; NaHSO<sub>3</sub> + H<sub>2</sub>SO<sub>4</sub> ---> NaHSO<sub>4</sub> + H<sub>2</sub>O + SO<sub>2</sub>.
And you might find a use for SO<sub>2</sub>.




Thanks for the feedback. I'll try this tomorrow, adding a strong acid to a mild acid should be better than adding a strong acid to a strong base! Adding sulfuric acid to conc. sodium hydroxide solution will cause it to instantly boil make a thunderous noise! I let you know how it went tomorrow.

&#9618;Nick&#9618; - 11-12-2011 at 18:12

I hate how these chemical names are so similiar! I actually needed to make sodium bisulfite out of sodium bisulfate, if its possible! Deeply sorry about that.

UnintentionalChaos - 11-12-2011 at 18:30

Quote: Originally posted by ▒Nick▒  
I hate how these chemical names are so similiar! I actually needed to make sodium bisulfite out of sodium bisulfate, if its possible! Deeply sorry about that.


Not really. Sodium metabisulfite (Na2S2O5) hydrates in water to sodium bisulfite and is extraordinarily cheap.

In fact, metabisulfite is significantly more stable than bisulfite in the solid phase and even aldrich reagent sodium bisulfite is a mix of actual bisulfite and metabisulfite. Assay is provided on SO2 content to make measuring possible.

[Edited on 12-12-11 by UnintentionalChaos]

hissingnoise - 12-12-2011 at 03:08

Bisulphites cannot be prepared from bisulphates as the reduction, being auto-catalysed, produces sulphides.
Leading SO<sub>2</sub> to a solution of hydroxide or carbonate will give bisulphite.
But, as UC said, hydrolysis of metabisulphite is convenient . . .


[Edited on 12-12-2011 by hissingnoise]

AndersHoveland - 12-12-2011 at 12:18

NaSO4H is sold inexpensively in pool supply stores, where it is used to lower pH.

&#9618;Nick&#9618; - 12-12-2011 at 12:25

Do they sell sodium metabisulfite in any hardware stores or anything? If not I'll just get it online.

sternman318 - 12-12-2011 at 20:53

Quote: Originally posted by ▒Nick▒  
Do they sell sodium metabisulfite in any hardware stores or anything? If not I'll just get it online.

http://www.homedepot.com/h_d1/N-5yc1v/R-202022334/h_d2/Produ...
Sodium pyrosulfite= sodium metabisulfite, you're in luck!

Arthur Dent - 13-12-2011 at 04:51

Two sources for what you are seeking:

Sodium Metabisulfite is often found at wine-making / beer-making supply stores, the Sodium Metabisulfite is used as a preservative in the bottling of homemade wine. Some places also sell Potassium metabisulfite, but it's usually much more expensive and it does the same thing.

Sodium Bisulfate is found at pool supply stores for adjusting water pH downwards. I bought a 1 Kg jar recently and it's quite inexpensive.

Robert

jsc - 13-12-2011 at 08:00

You realize of course that sea urchins consider sodium bisulfate a weapon of mass destruction.

&#9618;Nick&#9618; - 13-12-2011 at 13:59

Quote: Originally posted by sternman318  
Quote: Originally posted by ▒Nick▒  
Do they sell sodium metabisulfite in any hardware stores or anything? If not I'll just get it online.

http://www.homedepot.com/h_d1/N-5yc1v/R-202022334/h_d2/Produ...
Sodium pyrosulfite= sodium metabisulfite, you're in luck!


Thanks for the info! I go to home depot a lot, seems like the best place to get it.

Sedit - 13-12-2011 at 14:13

It makes no sense to attempt to convert either chemical to one or the other considering home depot sells both of these in large quantity very cheaply if you go just buy what you are after instead of trying to convert one to the other.

&#9618;Nick&#9618; - 13-12-2011 at 14:43

Quote: Originally posted by Sedit  
It makes no sense to attempt to convert either chemical to one or the other considering home depot sells both of these in large quantity very cheaply if you go just buy what you are after instead of trying to convert one to the other.


I'm not, I didn't know places sold sodium metabisulfite. If I can buy a chemical locally, I don't bother making it.

Sedit - 19-12-2011 at 17:19

I understand, I'm just making a point that its not only the fact that it is sold locally but they are both sold in the same store. That would make it highly odd to attempt the conversion of one to the other when you could walk a few isles over and grab the other.

It's akin to walking in the liquor store and trying to convert your Wisky into everclear... Just buy the everclear instead, right?