B(a)P
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Hydazine sulfate decomposition
I regularly make hydrazine sulfate using the well know method from urea and bleach. Following the synthesis I typically give it a recrystallisation
then leave it to dry in a dehydrator. Usually I would leave the product on a watch glass or evaporating dish, but in this instance I had none
available so left the product on the filter paper in the dehydrator. I promptly forgot about it then returned about 6 weeks later in need of some
hydrazine. The product had gone from white crystalline to a browny grey clumpy substance. I was unable to to get any free base hydrazine from the
product. I will give the remainder a recrystallisation to see if anything can be saved, but I think I have lost the lot. This is obviously a terrible
way to store chemicals, but out of curiosity any idea what happened here? I wouldn't have expected the HS to react with what is essentially cellulose.
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draculic acid69
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It sounds like either the hydrazine or some leftover bleach or something reacted with the cellulose.maybe excess sulfuric acid.
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B(a)P
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Ah, good point on the acid.
I don't know that residual hypochlorite would survive the reaction temperature, but maybe.
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Tsjerk
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At room temperature bleach turns to NaCl upon drying, NaClO (H2O)5 is known, but isolation is not that easy. Left over H2SO4 being concentrated during
the drying sounds more likely.
I had a similar problem lately with HCl, hydrochloric acid feels like it evaporates, but before doing so it actually concentrates quite a bit.
[Edited on 10-5-2020 by Tsjerk]
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