Sciencemadness Discussion Board

Cleaning buchner funnel after NHN synthesis

ManyInterests - 14-12-2021 at 19:46

I finally succeeded in making some NHN. I believe I filtered off all that I can filter off (the rest can be neutralized with sodium hydroxide before being flushed down the toilet, according to a Chinese research paper on Nickel hydrazine nitrate).

But the problem that in my first extraction I was drawing away a lot of stuff. The filter paper got clogged up (I poured lots of distilled water over it. Almost 200 ml, so i am not worried about the left over ethanol and hydrazine) I tried to remove the paper, but there was a lot of liquid in it. I could transfer to another filter paper, But I did see a video where some filtered that stuff directly on the frit and was fine... except I was wrong. While I did try to filter off as much of the NHN as possible between two flasks, no matter what I did, the stuff was still stuck to my buchner funnel.

I am trying to clean it off, but the NHN appears to be stuck there. I don't want any of that stuff going down the drain... unless it's safe for itty bitty bits of it to go down there (where it will likely be neutralized by a hydroxide at the water treatment facility...).

Any idea on cleaning this?

Funnel1.jpg - 1.3MBFunnel2.jpg - 1.3MB

ManyInterests - 14-12-2021 at 20:01

Actually wait. I think a sodium hydroxide solution will clear it. I need to wash it several times. It might take a while, but I think I see it clearing up already.

Edit: Most parts are clearing up, but I see some parts turning a little green. I think this is a nickel oxide forming.

[Edited on 15-12-2021 by ManyInterests]

fredsci93 - 14-12-2021 at 20:32

dilute sodium hydroxide wash followed by a dilute hydrochloric acid wash should work

ManyInterests - 14-12-2021 at 20:50

That sounds good. It's what I am doing now.

It is turning the NHN green, as neutralizing it seems to turn it into nickel(II) oxide. The green stuff.

It's going to take hours for the sodium hydroxide to drip it's way through, but I got plenty of time. Tomorrow I will dilute some HCl (how much do I need? how dilute does it have to be?) and let it filter very slowly through the stuff.

Will it be good for food safe stuff after that? I obviously need to water filter it many times for it to be fully clean, but that's something I can do.

fredsci93 - 14-12-2021 at 21:47

You should probably wash it more thoroughly with hydrochloric acid if you want to use it for food production, nickel is a carcinogen so it's not great for food making purposes, try a couple hydrochloric acid washes followed by a couple water washes

ManyInterests - 14-12-2021 at 22:21

Yep. Like you said in the other thread, 10% or 5%. I'll dilute some HCl tomorrow. I ran some quick sodium hydroxide through this, a slow run, and a third slow run. It'll be good by morning. I'll run regular water through it before the HCl. I'll make three HCl runs. I won't be using this for anything for a while so I'll just keep cleaning it.

If it makes it safe by then, that's all I care about.

karlos³ - 15-12-2021 at 02:58

In my own experience, I barely see such a clean büchner to begin with :D

The normal solution to this is, to create piranha acid(nibblewater, Knabberwasser) in the funnel to chew up all the crap.
Take care never to use acetone before or after.... still remember the not loud "thud!" sond after someone tried exactly that and the glass all shattered from in-situ acetone peroxide formed.

Triflic Acid - 15-12-2021 at 07:53

As a side note, when making explosives, I always keep a filter paper between the glass frit and the explosive. That way I'm not scrapping it out of glass frit. Now, I just use ceramic filter funnels altogether, which are much easier to clean. Glass frits are now reserved for acetone soluble organics only.

ManyInterests - 15-12-2021 at 11:25

Yeah I forgot about the acid washes and the whole process. Someone told me about an entire battery of tests that also involved non-polar solvents (like xylene). But at any rate. The sodium hydroxide took FOREVER to make it through the funnel, but I made it do it twice.

After which I used around 600ml of dilute HCl/hydrochloric acid solution and it went through it like no one's business. Not only that, but the frit is so crystal clear it is like brand new! I've run distilled water through it and I think it's all good now.

Quote:
As a side note, when making explosives, I always keep a filter paper between the glass frit and the explosive. That way I'm not scrapping it out of glass frit. Now, I just use ceramic filter funnels altogether, which are much easier to clean. Glass frits are now reserved for acetone soluble organics only.


Yeah, the filter paper got clogged REAL fast and I couldn't get it out because it was so full of liquid. If I could do it again, I would have poured far less on a single paper and replaced them frequently. But at any rate, it's all good now and my NHN is drying very nicely. Tonight I will take out what I have and give everything a steam bath to rapidly dry what is left.

The only synthesis I want to do after this is keto-RDX. I've done nitrations before. This one is a big challenge from what I heard. But nothing a shitload of ice can't handle. Also it's very chilly outside where I live so the ambient temperature will aid in keeping the nitration solution cold.

Triflic Acid - 15-12-2021 at 11:52

A bit of advice, do the reaction on a day that it snows. If you somehow run out of ice during the procedure, there is an infinite supply outside.

ManyInterests - 15-12-2021 at 20:51

Well it snowed quite heavily today, so I got a natural ice bath! :D

Herr Haber - 20-12-2021 at 05:43

Quote: Originally posted by ManyInterests  

Will it be good for food safe stuff after that? I obviously need to water filter it many times for it to be fully clean, but that's something I can do.


"Will my fritted funned that I used to filter a nickel based friction sensitive explosive be food safe ?"


You wont find me again on your threads. I do not wish to be part of your demise.
When you teach something to someone you become in part responsible for what they do with that knowledge.

stoichiometric_steve - 21-12-2021 at 05:06

Quote: Originally posted by Herr Haber  

"Will my fritted funned that I used to filter a nickel based friction sensitive explosive be food safe ?"


Absolutely. Although the food won't be safe for consumption