Uemura
That appears to bee THE WAY TO KCN, I didn't commemt because I had no new knowledge to add. We just need to get a purification scheme worked out and away we go.
Here is the DANGEROUS purification.
Add HCl and pipe HCN gas into Hydroxide solution with a tiny bit of pH indicator. Go until the hydroxide becomes neutral, then evap and recrystallize for pure NaCN or KCN.
Best done outside when there is a Stiff Breeze!!!
The purification of alkali cyanide melts.
Electrochim. Acta (1977), 22(4), 391-3.
Abstract
The impurities expected in alkali metal cyanides are discussed and methods for their removal from (K, Na)CN eutectic melts examd. Room-temp. vacuum-drying combined with melting of the salt with Si powder was the best purification method. The purity of the melts was evaluated by IR spectroscopy.
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