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

Printable Version  
Author: Subject: Sodum dithionite synthesis
ergoamide
Harmless
*




Posts: 33
Registered: 16-7-2006
Member Is Offline

Mood: No Mood

[*] posted on 16-7-2006 at 06:42
Sodum dithionite synthesis


Ok first post on here lets see how i go,

I'm after help on a sodium dithionite synth. I checked the rhodium archive and found a zinc dithionate synth, and i was thinkin using simple skils if you placed NaOH in there the NaOH would displace the Zn a a more reavtive metal and Zn would precipitate out (Zn(OH)2 is very soluble is it). Of course thers the formate procedure but i don't have access to formates. The i read on the wikipedia that sodium bisulphite can be reduced by Zn to sodium dithionate directly.

I can't myself see any problems with the reaction as Zn reduces the free acid to the dithionate, the hydrogen isn't involved in it so i figure neither will the sodium. So if it works which i'm prettys ure it should then all you would really have to do is make a sodium bisulphite solution then add a slight molar excess of Zn powder and wait until most fo the Zn powder has been consumed and filter off the Zn(OH)2.

So what are your opinions, what tweaks should i make to make this work better (assuming it does work).

EbC: title spelling

[Edited on 19-7-2006 by chemoleo]
View user's profile View All Posts By User
solo
International Hazard
*****




Posts: 3975
Registered: 9-12-2002
Location: Estados Unidos de La Republica Mexicana
Member Is Offline

Mood: ....getting old and drowning in a sea of knowledge

[*] posted on 16-7-2006 at 08:07


Reference Information


A method for preparing analytically pure sodium dithionite. Dithionite quality and observed nitrogenase-specific activities
Charles E. McKenna, William G. Gutheil and Wei Song
Biochimica et Biophysica Acta (BBA) - General Subjects, Volume 1075, Issue 1, 2 September 1991, Pages 109-117

http://rapidshare.de/files/26079764/A_method_for_preparing_a...

Abstract
Sodium dithionite (NazSzO 4) is widely used as a reductant in biochemical studies, but has not been available in its pure form. A convenient, detailed procedure is given for the recrystallization of commercial dithionite from 0.1 M NaOH-methanol under anaerobic conditions. Twice-recrystallized dithionite had a purity of 99 _+ 1% by IN spectroscopy (A3I s) and elemental analysis. The influence of dithionite quality on the apparent reduction activities of the nitrogenase components (Avl and Av2) from Ay.otobacter vinelandii was investigated.




[Edited on 17-7-2006 by solo]

Attachment: A method for preparing analytically pure sodium dithionite.pdf (676kB)
This file has been downloaded 5323 times





It's better to die on your feet, than live on your knees....Emiliano Zapata.
View user's profile View All Posts By User
ergoamide
Harmless
*




Posts: 33
Registered: 16-7-2006
Member Is Offline

Mood: No Mood

[*] posted on 16-7-2006 at 22:34


oh dam the file wont let me download ti it keeps comin up with filel cannot be written to cache. crap arse computer.
View user's profile View All Posts By User
acetate
Hazard to Others
***




Posts: 116
Registered: 27-8-2005
Location: Europe
Member Is Offline

Mood: LUMO

[*] posted on 19-7-2006 at 07:36


Copy from publication:

Angewandte Chemie International Edition in English
Volume 18, Issue 4 , Pages 313 - 314


Quote:

A solution of SOz (212 g) in methanol (636 g) and a solution
of sodium formate (120g) in water (106g) are simultaneously
added (50 % of each solution in 15 min and the rest within
7.5 min) to a suspension of sodium formate (1 20 g), NaOH(solid)
(9Og), water (382g), and methanol (402g) in a 2-1 glass
flask fitted with a stirrer and two entry tubes; the temperature
is kept at 67°C during the addition. After cooling to 60°C,
the solid material is filtered off, washed with methanol, and
dried. In this way, 211 g of a crystalline product is obtained
which consists of Na2S2O5.NaOOCH (94.5 %), Na2S2O4
(2.3 %), Na2SO3 (3.0 %), and Na2S2O3 (0.2 %); the yield of
Na2S205.NaOOCH is 46.7 % based on SO2.



... I have "old" preparation of Na2S2O4 from HCOOH, HCOONa and Na2S2O5 in ethanol/H2O but I dont know how it is good ... if you want I will must translate this preparation ...

Attachment: Na2S2O4.pdf (255kB)
This file has been downloaded 1182 times





//--- ---//
View user's profile View All Posts By User
ergoamide
Harmless
*




Posts: 33
Registered: 16-7-2006
Member Is Offline

Mood: No Mood

[*] posted on 20-7-2006 at 22:54


I was more wondering if anyone had some conformation about using a bisulfite solution but no worries i know that it works now they sometimes use it industrially. Now all i need to know is an efficient way of separating it form zinc hydroxide.
View user's profile View All Posts By User
neutrino
International Hazard
*****




Posts: 1583
Registered: 20-8-2004
Location: USA
Member Is Offline

Mood: oscillating

[*] posted on 21-7-2006 at 06:42


Zinc hydroxide is insoluble in water. Just filter or decant the mixture.



View user's profile View All Posts By User

  Go To Top