Sciencemadness Discussion Board

Lithium nitride

j_sum1 - 9-12-2020 at 03:11

Does anyone have any experience with lithium nitride?

I have some lithium rods that are very old and have been stored pooorly. The outer 1mm of the rods is a dark grey crusty material that crumbles off when the rods are bent. My assumption is that this crust contains quite a bit of Li3N as well as oxide and hydroxide and intrained metal.

Looking at the physical properties it would seem to be a straightforward process to separate relatively pure lithoim out by melting: probably with inert gas and a hydrocarbon to separate the layers.

Next question is how to isolate the Li3N. It is supposed to be a purple-red colour. I can test for its presence by dropping a little in water to see if ammonia is produced. And if ghere is some... Well, any ideas?


[Edit - saving face on a novice error.]

[Edited on 9-12-2020 by j_sum1]

B(a)P - 9-12-2020 at 03:14

I think your '3' is in the wrong spot. Presumably you don't have lithium azide?

Edit: sorry couldn't help myself, I just get so excited when I see N3.

[Edited on 9-12-2020 by B(a)P]

j_sum1 - 9-12-2020 at 03:50

Quote: Originally posted by B(a)P  
I think your '3' is in the wrong spot. Presumably you don't have lithium azide?

Edit: sorry couldn't help myself, I just get so excited when I see N3.

[Edited on 9-12-2020 by B(a)P]

Not once but twice. I must be a lot more tired than I thought. Good thing I am not in the lab at the moment.
I sm going to have to edit that before someone notices: just to save mysekf dome embarrasment.

clearly_not_atara - 9-12-2020 at 08:49

Don't worry yoursekf too much, lithoim is cheap. But maybe get dome sleep.

Apparently the reaction of Li3N with CO2 can give C3N4. This is a pretty cool trick I would think: it won't isolate Li3N, but you could simply grind the unfused materials, suspend in a hydrocarbon and bubble CO2. I'm not sure if Li2O/LiOH present will affect the result, though.

https://pubs.acs.org/doi/10.1021/jp205499e