flipper (Hive Bee)
05-05-02 11:35
No 305174
      A dumb question about hydrazine  Bookmark   

Are these two syntheses the same

2NH3+NaOCl------>NH2-NH2
NH2-NH2+H2SO4------>NH2-NH2.H2SO4

and this

N2 + 4H2O + 4e-  ---> 4OH + NH2-NH2 (Raschig route)

I know i'm a amateur but redox and the shit with electrons are fucking my mind. 

   

You've gotta love me.
 
 
 
 
    Rhodium
(Chief Bee)
05-05-02 12:11
No 305182
      No, it is two distinct synthetic routes where in ...  Bookmark   

No, it is two distinct synthetic routes where in the first ammonia is oxidized to hydrazine with sodium hypochlorite, and in the second nitrogen gas is reduced to hydrazine.

2 NH3 -Oxidation-> NH2-NH2 <-Reduction- N2
 
 
 
 
    flipper
(Hive Bee)
05-05-02 14:21
No 305220
      Something I've found  Bookmark   

I've found some things on the web



It is a viscious cycle beginning and ending with ammonia (NH3) and hydrazine (N2H2). First amm. and sodium hypochlorite form hydrazine: 2NH3 + NaOCl --> N2H4 + NaCl + H2O. Chloramine (NH2Cl) is formed with ammonia and hypochlorite: NH3 + OCl- --> NH2Cl + OH-. Then chloramine converts back to hydrazine and aqueous chlorine: NH2Cl + NH3 --> N2H5+ + Cl-.





Anyway, chloramine is a generic term used to describe either NH2Cl (monochloramine) or NHCl2 (dichloramine). They are formed by reacting hypochlorous acid with ammonia:
Start with chlorine to get hydrochloric acid and hypochlorous acid (HOCL):
Cl2 + H2O = HCl + HOCl (This is a pH dependant *equilibrium*.)
Add ammonia:
NH3 + HOCl = NH2Cl + H2O
Add more chlorine:
NH2Cl +HOCl = NHCl2 + H2O
Add too much chlorine:
2NHCl2 + H2O = HOCl + 3H+ + 3Cl- + N2

For chlorine, the reaction with sodium thiosulfate is:
2Na2S2O3 + Cl2 = 2NaCl + Na2S4O6

I won't guess on the reaction with chloramine and sodium thiosulfate, but it seems perfectly reasonable the common report of releasing ammonia into the water when attempting to neutralize chloramine with sodium thiosulfate.




NH2NH2, m.p. 1.4C, b.p. 113.5C, specific gravity 1.011 at 15C. It is very soluble in water and soluble in alcohol. At ordinary temperatures it is a colorless, fuming liquid that has an ammonialike odor, but when frozen it forms white crystals. Hydrazine is corrosive and a strong reducing agent, but it is a weaker base than ammonia. It reacts with water to form hydrazine hydrate, N2H4H2O, a colorless liquid that boils at 120C. Hydrazine can be prepared (usually as the hydrate) by reacting ammonia with chloramine, NH2Cl, in the presence of glue or gelatin. The glue or gelatin inhibits decomposition of the hydrazine. Ammonium chloride is a byproduct. The chloramine may be prepared by reacting ammonia with a hypochlorite or chlorine gas. Hydrazine is also prepared by reaction of sodium hypochlorite with urea in the presence of glue or gelatin.

IMPORTANT

My question is??
I wanna know the procedure how to synthesize Chloramine and how to make Hydrazine from Hydrazine. How to make Hydrazine without something cheesy like gelatin. And how to perform this reaction. N2 + 4H2O + 4e-  ---> 4OH + NH2-NH2 (Raschig route)

smile laugh smile laugh smile laugh smile laugh smile laugh smile laugh smile laugh
This is a funny patent from 1937. Maybe you didn't know this one maybe you did: The preparation of lysergic acid hydrazide (http://l2.espacenet.com/espacenet/viewer?PN=GB463936&CY=gb&LG=en&DB=EPD)


You've gotta love me.
 
 
 
 
    nevry
(Stranger)
05-07-02 19:07
No 306026
      re:...  Bookmark   

a colloid is necessary(ie gelatin). If you think gelatin is 'cheezy' then you could use starch instead wink

- nevry.
 
 
 
 
    Osmium
(Stoni's sexual toy)
05-08-02 04:33
No 306204
      No. The gelatin will remove traces of heavy ...  Bookmark   

No.
The gelatin will remove traces of heavy metals which will decompose the intermediates and the hydrazine. Starch won't do that.

I'm not fat just horizontally disproportionate.
 
 
 
 
    nevry
(Stranger)
05-08-02 04:59
No 306213
      i guess you're smarter than merck  Bookmark   

although my merck is a bit old, production of hydrazine doesn't change.

"H2NNH2.H2SO4; mol wt 130.13... ...Prepd by Raschig synthesis: 2NH3.aq + [Ca(OCl)2/NaCO3/Colloid] and treatment with H2SO4. Starch, glue, or gelatin are used as colloids, and sodium hypochloride may be used instead of bleaching powder..."

- nevry.

- nevry.
 
 
 
 
    Osmium
(Stoni's sexual toy)
05-08-02 09:17
No 306294
      > i guess you're smarter than merck That is ...  Bookmark   

> i guess you're smarter than merck 

That is very well possible! wink

I have refs at home that explicitly say that the glue (animal glue) or gelatin are added to remove traces of heavy metals. I don't think that starch will do that.

I'm not fat just horizontally disproportionate.