lysander - 15-1-2016 at 10:35
Typical methods of producing HCN result in a solution with water. Distilling it can produce a more stable product. But for small batches I'm wondering if it couldn't be dehydrated with a standard desiccant salt.
Would MgSO4 or CaSO4 be effective at dehydrating a HCN solution (in particular, by not reacting with the HCN)?
MrHomeScientist - 15-1-2016 at 13:49
Generally desiccants are used to remove the last remaining traces of water from a damp solid (or liquid, like acetone) - if it's an aqueous solution
of a compound, they won't do much. You're better off evaporating or distilling. More information on your process would be helpful, especially when
dealing with cyanides. Don't do anything until you understand the situation fully and prepare accordingly.
lysander - 15-1-2016 at 14:22
Distillation is a good solution, but for HCN it looks more tricky to setup. This patent on a distillation method for dehydrating HCN notes it as a more productive alternative to "the use of dehydrating agents, for
example molecular sieves...." Which left me wondering what dehydrating agents would be effective at a small scale, or where high-grade distillation
equipment isn't available.
unionised - 16-1-2016 at 07:51
In addition to being notably toxic, HCN is also explosively unstable- particularly in the presence of bases. That rules out some drying agents.
It's also inconveniently volatile.