ergoamide
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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]
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solo
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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 5276 times
It's better to die on your feet, than live on your knees....Emiliano Zapata.
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ergoamide
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oh dam the file wont let me download ti it keeps comin up with filel cannot be written to cache. crap arse computer.
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acetate
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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 1155 times
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ergoamide
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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.
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neutrino
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Zinc hydroxide is insoluble in water. Just filter or decant the mixture.
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