Fifty years ago I had very limited amounts of H2SO4 and I made HNO3 by the dry distillation of KNO3, CuSO4 and alum, but I could not remember the
stoichiometry.
I found a contemporary reference which gives the following quantities: 150 gm of KNO3, 150 gm of CuSO4, and 50 gm of KAl(SO4)2. Yield is said to be
70 gm of about 50% HNO3.
The reference states that the dry distillation was conducted at 800 C, but I believe it must be possible at lower temperatures because I used a Pyrex
retort and it was not damaged. I still have the retort.
This worked fifty years ago and I suspect it will work in the 21st century. I cannot recall my yields, but they were not trivial.
The reference is here: http://www.chemicke-listy.cz/docs/full/2002_12_05.pdf |
