Sciencemadness Discussion Board
Not logged in [Login ]
Go To Bottom

Printable Version  
Author: Subject: how can I separate Sodium hydrosulfite and sodium bisulfite mixture?
LD5050
Hazard to Others
***




Posts: 182
Registered: 16-1-2017
Member Is Offline

Mood: No Mood

[*] posted on 15-3-2017 at 20:45
how can I separate Sodium hydrosulfite and sodium bisulfite mixture?


I found a toilet rust remover powder the ingredients are Sodium hydrosulfite and sodium metabisulfite. I would like to separate the two and collect the Sodium Bisulfite how could I do this?
View user's profile View All Posts By User
Texium
Administrator
********




Posts: 4581
Registered: 11-1-2014
Location: Salt Lake City
Member Is Offline

Mood: PhD candidate!

[*] posted on 15-3-2017 at 21:18


Firstly, what is the brand? I've been trying to find good OTC sodium hydrosulfite (dithionite) for a while now, so I'm more interested in that component.

You shouldn't need to separate them though, especially not if you need to use the bisulfite in solution. Dissolving it in water and heating the solution gently for a while should convert most of the dithionite to bisulfite and thiosulfate. And, if you just need it as a general reducing agent, using it as-is should be fine.




Come check out the Official Sciencemadness Wiki
They're not really active right now, but here's my YouTube channel and my blog.
View user's profile Visit user's homepage View All Posts By User
Texium
Administrator
Thread Moved
15-3-2017 at 21:18
j_sum1
Administrator
********




Posts: 6324
Registered: 4-10-2014
Location: At home
Member Is Offline

Mood: Most of the ducks are in a row

[*] posted on 15-3-2017 at 21:45


IIRC, Nurdrage uses an OTC source of dithionite in his recent video on a luminescent oscillating reaction. I can't check right now. But I know I saw it recently.
View user's profile View All Posts By User
LD5050
Hazard to Others
***




Posts: 182
Registered: 16-1-2017
Member Is Offline

Mood: No Mood

[*] posted on 15-3-2017 at 21:49


so the brand is Iron Out and on it says "rust and stain remover" with a picture of a toilet on it. It says its contains Sodium Hydrosulfite and sodium metabisulfite. I want the bisulfite to purify benzaldehyde by forming the adduct.

Oh ya I checked the MSDS and it say it contains 20-40% hydrosulfite and 20-40% bisulfite. Along with a couple other things of tiny percentages like citric acid and Sodium carbonate maybe? if I rember correctly

[Edited on 3-16-2017 by LD5050]
View user's profile View All Posts By User
j_sum1
Administrator
********




Posts: 6324
Registered: 4-10-2014
Location: At home
Member Is Offline

Mood: Most of the ducks are in a row

[*] posted on 15-3-2017 at 22:18


If the metabisulfite is what you are after, IME, the easiest OTC source is brewers' suppliers. It is used for disinfecting bottles.
Bisulfites are not too tricky to obtain from SO2 if you have a source of sulfur. (Ask Daffodile for some. :))
View user's profile View All Posts By User
LD5050
Hazard to Others
***




Posts: 182
Registered: 16-1-2017
Member Is Offline

Mood: No Mood

[*] posted on 16-3-2017 at 06:24


Ya the only brewing supply store is kinda far from me so I wanted to find another option.
View user's profile View All Posts By User
Corrosive Joeseph
National Hazard
****




Posts: 915
Registered: 17-5-2015
Location: The Other Place
Member Is Offline

Mood: Cyclic

[*] posted on 16-3-2017 at 18:10


If you do find a decent separation method, please post it.............

Sodium hydrosulfite - AKA - https://en.wikipedia.org/wiki/Sodium_dithionite - is also very useful, it will reduce aldehydes and ketones................ And according to Weygand and Hilgetag (Preparative Organic Chemistry 1972), it was 'previously much used to reduce carbon-carbon multiple bonds'................

I'm sure there are plenty more applications for it.............

PS - Just buy the metabisulfite at the brew shop.............. ;)


/CJ

[Edited on 17-3-2017 by Corrosive Joeseph]




Being well adjusted to a sick society is no measure of one's mental health
View user's profile View All Posts By User
Amos
International Hazard
*****




Posts: 1406
Registered: 25-3-2014
Location: Yes
Member Is Offline

Mood: No

[*] posted on 17-3-2017 at 09:40


If you happen to be in the states, I'd suggest getting Bonide Stump Remover at a hardware store; it's pure sodium metabisulfite and goes for like $6/454g.

The rust remover sounds interesting, since you can react the sodium metabisulfite portion with zinc in solution to get sodium dithionite alone; thus reducing the amount of zinc you'd need to synthesize it from bisulfite anyway.
View user's profile View All Posts By User
Corrosive Joeseph
National Hazard
****




Posts: 915
Registered: 17-5-2015
Location: The Other Place
Member Is Offline

Mood: Cyclic

[*] posted on 17-3-2017 at 12:10


Quote: Originally posted by Amos  
you can react the sodium metabisulfite portion with zinc in solution to get sodium dithionite alone;


Quality piece of information there. Hopefully that could be done without even separating a mixture of the two.

Apologies for topic drift..................


/CJ





Being well adjusted to a sick society is no measure of one's mental health
View user's profile View All Posts By User
LD5050
Hazard to Others
***




Posts: 182
Registered: 16-1-2017
Member Is Offline

Mood: No Mood

[*] posted on 17-3-2017 at 21:34


I looked around and wasnt able to find the stump remover anywhere. I purchased the rust out tho so any idea on how to purify it so I can use it to make adducts of ketones would be helpful thanks in advance.
View user's profile View All Posts By User
JJay
International Hazard
*****




Posts: 3440
Registered: 15-10-2015
Member Is Offline


[*] posted on 17-3-2017 at 21:50


Quote: Originally posted by Corrosive Joeseph  
Quote: Originally posted by Amos  
you can react the sodium metabisulfite portion with zinc in solution to get sodium dithionite alone;


Quality piece of information there. Hopefully that could be done without even separating a mixture of the two.

Apologies for topic drift..................


/CJ



That *is* a quality piece of information. I'm going to have to try that.

As to the OP's question, you could probably dissolve the mixture in water and fractionally crystallize. The sodium dithionite should crystallize first. Note that oxygen will dissolve in the water and slowly destroy your sodium bisulfite, and this is likely to be a messy procedure with lots of bumping, difficult filtrations, sulfurous smells, and fairly noxious fumes.

Personally, I would just keep my eyes peeled and pick up a large sack of it at my earliest opportunity or perhaps try making some by burning sulfur. It's an extremely common chemical.




View user's profile View All Posts By User

  Go To Top