Rhodanide - 28-3-2017 at 07:30
So, the other day I tried my hand at making Boron Nitride. I was going to go with the route of reacting molten Sodium Tetraborate with Ammonium
chloride, as one synthesis suggested. I had doubts about this at first, but I tried it anyways. I successfully melted the STB in an old steel camping
dish over a propane torch set on maximum. I added the Ammonium Chloride and got what I expected. A buddy of mine thought there was a fire, because of
the amount of white, acrid smoke produced. (May I also mention that this stained anything downwind white... how lovely...)
I don't have Urea (required for another route) which rules out the other, likely easier option of B2O3 + (NH2)2CO. I was wondering if anyone knows of
a way to synthesize Boron Nitride in solution, and if not then a process that doesn't make a smoke bomb would be preferable.
halogen - 4-4-2017 at 19:47
You DO have urea. Now-a-days messing around with urine would be considered a sign of insanity, however, as a result of the use in terrorist bombings
of the now obsolete ammonium nitrate in instant, self contained cold "packs" for injuries, relatively pure urea is a common item. You would have to
actually look to find urea fertilizer, which is also common, and, per mole, presumably cheaper.
You will not make boron nitride in aquatic solution.
gluon47 - 4-4-2017 at 20:08
I have successfully prepared boron nitride by both methods. Ammonium chloride + sodium tetraborate gave a low yield and an impure product for me. Urea
+ boron trioxide gave a fairly pure product and an acceptable yield (my writeup here).
As strange as it may seem, boron nitride reacts with hot water. I made the mistake of using hot water several times and destroying all my product.
BN + 3 H2O ==> B(OH)3 + NH3
I would definitely suggest getting some urea (as suggested by halogen) if you want to make boron nitride. good luck
.