Sciencemadness Discussion Board

welshwing's Thread of Many Questions

welshwing - 6-1-2016 at 09:00

Do these harmless substances really create NaCN?
Hello, I am looking to make a very small amount of cyanide. I have all the safety precautions so nobody will get hurt, in the end I will dispose of the cyanide by burying it in an isolated area inside of a thick glass bottle.

Here are the reactants I was going to use
Charcoal
Sodium carbonate
Cyanuric acid

Sodium carbonate + cyanuric acid = sodium cyanate

sodium cyante + charcoal = sodium cyanide


I think it's common sense sodium carbonate and charcoal aren't deadly, in small amounts (even sugar is deadly in large amounts). I checked and neither sodium cyanate or cyanuric acid are deadly, then why/how do they create NaCN which is highly poisonous? It makes sense because burning charcoal creates a fume as deadly as CN- but why????

[Edited on 6-1-2016 by welshwing]

[Edited on 3-2-2016 by zts16]

ParadoxChem126 - 6-1-2016 at 09:42

It is not uncommon for "safe" chemicals to react to form toxic ones. The toxicity of a chemical is largely dependent on its structure and reactivity. Cyanide happens to be an inhibitor to the cytochrome C oxidase, while its precursors are not. For this reason, it is more toxic.

I would not suggest experimenting with cyanide if you are new to hobby chemistry. Also, it would be much better to dispose of cyanide by chemically destroying it. Alkaline bleach is capable of neutralizing cyanide, see the following link:

http://www.sciencemadness.org/talk/viewthread.php?tid=9146#p...

Bert - 6-1-2016 at 09:52

http://www.sciencemadness.org/talk/viewthread.php?tid=23



AJKOER - 6-1-2016 at 11:37

OK, it is also apparently true that harmful elements can combine to form safe, and at times, essential compounds for human life. Example, highly reactive Sodium metal and poisonous Chlorine gas, forming salt.

But don't try this dangerous synthesis at home, very exothermic, but salt itself is considered safe. :D

[Edited on 6-1-2016 by AJKOER]

Is the bathroom fan enough to remove fumes?

welshwing - 7-1-2016 at 05:16

I can't afford an expensive fume hood, I just need something to send the fumes outside where nobody will get hurt from them. The bathroom fan makes the steam go away during a shower, is that good enough to remove chemical fumes?

If not what can I do? Making chemical reactions in my backyard will look suspicious to the neighbors. Would you suggest making one out of construction paper that leads from the crucible to my window?

Detonationology - 7-1-2016 at 05:35

No, no, no.

1. Many gasses produced in the lab are much too dense to be sucked out by a weak draft.
2. Many vapors produced in the lab are volatile and flammable. Typical fans produce sparks during operation.
3. Many gases produced in the lab are corrosive. The metal vent would likely rust very quickly.

Stick with outside for now. I have a fume hood that is in the process of being put up in my garage, and the outside isn' too bad.

MrHomeScientist - 7-1-2016 at 06:27

When it's your life at stake, you don't want to "cheap out" on safety.

Sulaiman - 7-1-2016 at 08:23

After my recent round of experimets, in answer to "Is the bathroom fan enough to remove fumes?"
I say YES ... eventually
but definitely too slowly to protect you when reactions are not as gentle as you expect, to put it mildly

(e.g. reactions involving conc. HNO3 usually seem fairly inactive, until temperature rises
... then unbelievable quantities of gas with an evil shade of brown spew into the air, and you learn what NO2 smells like ;)


Bert - 7-1-2016 at 08:42

NO!

GO OUTSIDE!!! If the neighbors don't like what they see, build a lean-too.

Get a fire extinguisher too.

Don't injure or kill yourself, or your family.

How well can you handle setting fire to a paper or cardboard hood inside your home, along with ignition of any flammable chemicals you were working with, mixed up with the now released toxic fumes you thought you were going to exhaust?


image.jpg - 30kB

Boffis - 7-1-2016 at 10:53

I disagree with Detonationolgy's comment too.

First bathroom fans come in various sizes based on the cfm or cmm (ie cubic feet or meter/minute they will shift. The smaller sizes require a 4" duct for which I used a length of waste water pipe set into the wall. The larger volume fans require 6" ducts but give much greater air flow volumes. The maximum volume of air for a 4" duct is about 1.5 m3 per minute but with a 6" dusct you can get up to about 4 m3 per minute. If that isn't enough, holy shit, how big is you fume hood? My fume hood has a volume of about 0.5 m3 and the fan shifts 1.2 m3/minute. This I have found to be quite adequate and I work with N2O4, ether, alkali cyanides, hydrogen sulphide etc without any problems.

Most extractor fans sold in Europe and all that I have seen in the UK are axial inductive motor types so no sparks unless you f**k up the wiring. :D

Corrosion of the duct? No problem use PVC or ceramic waste water pipes, they are cheap and easier to work with than steel.

One thing I would say is that no matter how much flow through your fume hood you have its no good if gas generation exceeds this flow rate. Once again there is no substitute for careful planning of your experiments. I recently carried out a synthesis with acetyl chloride in which all of the chlorine is evolved as hydrogen chloride, a simple but carefully constructed gas scrubber absorbed all of this into water and none was release into the air.

Bert - 7-1-2016 at 11:01

I believe the OP meant he literally intended to work in an existing bathroom- And use the installed exhaust fan in lieu of setting up a proper hood.

About the worst idea I could think of, after working in his mother's kitchen. But I have seem ignorant people doing just that in far too many YouRube videos...

Let's add link to this thread, regarding a couple of recently dead amateurs?

Detonationology - 7-1-2016 at 11:43

Quote: Originally posted by Boffis  
...the fan shifts 1.2 m3/minute. This I have found to be quite adequate and I work with N2O4, ether, alkali cyanides, hydrogen sulphide etc without any problems.

I find it rather hard to believe that such gasses could be readily removed from a lab area without any problems whatsoever. I often find myself semi-conscious, nearly asphyxiated, gasping for fresh air subsequent to making a deposit of Taco Bell in the facilities, even with the fan blower on. With that in mind, I would not conduct lab work in such a room containing even more noxious or toxic gasses.

[Edited on 1-7-2016 by Detonationology]

JJay - 7-1-2016 at 12:10

I occasionally do run chemical reactions using a bathroom fan for ventilation, and they work well for many purposes, but I don't consider them adequate for working with anything more dangerous than acetone.

1.5 m3/minute is not really adequate for doing most chemical reactions that are said to require a hood. I would consider 400 CFM (about 10 m3/minute) adequate for any purpose unless the hood is very large or you're doing something extraordinarily dangerous.

[Edited on 7-1-2016 by JJay]

Starcruiser - 7-1-2016 at 13:21

Simply using your bathroom, even with the fan employed, is not a good idea.

But a bathroom fan is ok for a small fume hood (mine is about 50x70x90 cm) as long as you do not make copious amounts of noxious fumes. Of course, noxious / dangerous fumes should not be simply vented outside - think of other people too not just you (also, attracting attention is not something to be desired). Scrubbers are a must before venting.

You can make a simple experiment to test your ventilation : light a small smoke bomb (about 2 g of a 60:30 KNO3 and sugar mixture). Take precautions, try not to set your house on fire.






welshwing - 7-1-2016 at 13:54

Quote: Originally posted by Starcruiser  
Simply using your bathroom, even with the fan employed, is not a good idea.

But a bathroom fan is ok for a small fume hood (mine is about 50x70x90 cm) as long as you do not make copious amounts of noxious fumes. Of course, noxious / dangerous fumes should not be simply vented outside - think of other people too not just you (also, attracting attention is not something to be desired). Scrubbers are a must before venting.

You can make a simple experiment to test your ventilation : light a small smoke bomb (about 2 g of a 60:30 KNO3 and sugar mixture). Take precautions, try not to set your house on fire.







Are you suggesting it isn't safe to create carbon monoxide outside near houses (like in my backyard)? Because neighbors grill and that releases the deadly fume, I would think doing it in the open air wouldn't be harmful to anyone.

I only thought of the bathroom because of how quickly it removes steam, and I would've done it if the response here was positive but I never considered actually doing it without feedback from here.

[Edited on 7-1-2016 by welshwing]

aga - 7-1-2016 at 14:16

A bathroom fan is what i have in my tiny fume hood.

The fume cupboard is in the middle of nowhere with the nearest neighbour 400m away.

So far it has done OK.

On a couple of occasions it was not powerful enough to remove the sheer volume of nasty gas i was producing at the time.

Mostly it has been OK.

The fume hood design & fan power depend entirely on what gasses you expect to produce, where you are, and if you want to survive.

blogfast25 - 7-1-2016 at 14:24

Quote: Originally posted by aga  
A bathroom fan is what i have in my tiny fume hood.

The fume cupboard is in the middle of nowhere with the nearest neighbour 400m away.

So far it has done OK.



Even in a professional fume cabinet overall air through-flow isn't very high as that wouldn't be practical either. So it's a question of balance between cabinet size and ventilator fan power.

aga - 7-1-2016 at 14:34

The main thing is to Calculate how much gas your intended reaction could produce, and plan accordingly.

As a general rule i use 22.4 Litres for every mol that could be produced, then hang the gas mask near the door or not, just in case the fan is not powerful enough.

There is really no excuse for Not Knowing when all the information is already available, either by 10 seconds googling or by asking here.

JJay - 7-1-2016 at 15:00

According to Prudent Practices in the Laboratory: Handling and Disposal of Chemicals, the usual fume hood face velocity should be 80-100 fpm, although 100-120 fpm should be used if handling exceptionally toxic substances or if circumstances that affect fume hood performance exist

JJay - 7-1-2016 at 15:01

Quote: Originally posted by aga  
The main thing is to Calculate how much gas your intended reaction could produce, and plan accordingly.

As a general rule i use 22.4 Litres for every mol that could be produced, then hang the gas mask near the door or not, just in case the fan is not powerful enough.

There is really no excuse for Not Knowing when all the information is already available, either by 10 seconds googling or by asking here.


It's probably a good idea to have a respirator nearby in case the power goes out.

Bert - 7-1-2016 at 16:42

Quote:
hang the gas mask near the door or not, just in case the fan is not powerful enough.


It's probably an even BETTER idea to just wear the fracking mask (WITH the appropriate cartridges) from the get-go if you've got anything really nasty going on and are working indoors with improvised equipment and a home made air extraction system.

Oh yeah, and to use fresh cartridges. Because absorptive or reactive filter media have only so much capacity, and will crap up with stray stuff from the atmosphere between uses if not carefully stored.

JJay - 7-1-2016 at 16:59

Yeah, if you're making phosgene or atomizing nickel carbonyl, you'll want to have your mask on already even if working in the hood.

You can occasionally get away with working indoors with less dangerous but harmful substances with a mask, but it's considered hazardous and should be done only when necessary.

Can I use a porcelain cup and piece of glass as a crucible?

welshwing - 1-3-2016 at 18:58

If I do something that a porcelain crucible is preferred, can I just use a small porcelain cream cup instead of buying the crucible?

Also, would it be okay to use any piece of glass to cover it, so I can see the reaction while it is happening?

Can I use a portable Bunsen Burner, one that can be taken anywhere?

welshwing - 1-3-2016 at 19:04

My family doesn't want me burning stuff in the house though I made a fume hood. I understand but not even in the backyard is okay, so how do cope?

Can you recommend to me a Bunsen Burner that has the fuel supply attached to it so you can carry it around everywhere?

Great - 1-3-2016 at 20:03

Where are you located? Lots of places here sell portable butane burners and stoves.

Great - 1-3-2016 at 20:04

It will break very fast, depending on how hot you heat it.

welshwing - 1-3-2016 at 20:08

Quote: Originally posted by Great  
It will break very fast, depending on how hot you heat it.


Ok. Is the glass cover okay so I can watch the reaction taking place?

Great - 1-3-2016 at 20:09

How high are you heating it?

welshwing - 1-3-2016 at 20:10

Quote: Originally posted by Great  
Where are you located? Lots of places here sell portable butane burners and stoves.


Thanks! I am in USA. I can use the iternet / google to buy one. Which of these from this link would you maybe buy if you were me? https://www.google.com/search?q=buy+bunsen+burner&oq=buy...

welshwing - 1-3-2016 at 20:13

Quote: Originally posted by Great  
How high are you heating it?


600 C, up to 700 C

Great - 1-3-2016 at 20:18

Quote: Originally posted by welshwing  
Quote: Originally posted by Great  
How high are you heating it?


600 C, up to 700 C


Don't use glass, I'd just recommend watching it with safety goggles. The glass will shatter into your dish, contaminating your product with shards, and messing up your workspace.

Also, use a different crucible material, like steel, copper, or graphite. The porcelain will likely break as well at high temperatures. If you can't find a good alternate crucible, improvise. I'm constantly impressed with the things people in the forum come up with to combat this problem, and I myself have also fashioned a few ghetto crucibles to do the job.

EDIT: What are you making anyhow? Depending on what it is, some materials would be better than others.

[Edited on 2-3-2016 by Great]

welshwing - 1-3-2016 at 20:21

Quote: Originally posted by Great  
Quote: Originally posted by welshwing  
Quote: Originally posted by Great  
How high are you heating it?


600 C, up to 700 C


Don't use glass, I'd just recommend watching it with safety goggles. The glass will shatter into your dish, contaminating your product with shards, and messing up your workspace.

Also, use a different crucible material, like steel, copper, or graphite. The porcelain will likely break as well at high temperatures. If you can't find a good alternate crucible, improvise. I'm constantly impressed with the things people in the forum come up with to combat this problem, and I myself have also fashioned a few ghetto crucibles to do the job.


I gotta go soon,

But if I don't use a cover won't oxygen effect the reaction? I was always told covering it will allow fumes to escape without allowing much oxygen into it

Zyklon-A - 2-3-2016 at 06:22

Use a steel can and lid. I doubt many portable Bunsen burners will get it hot enough. I'd build a charcoal forge, real cheap and can do 600°C no problem. Failing that, you could buy a propane torch at a hardware store for less than $20.
Be careful.

Herr Haber - 2-3-2016 at 13:07

Quote: Originally posted by Bert  


It's probably an even BETTER idea to just wear the fracking mask (WITH the appropriate cartridges)


Me and many people around here seem to be working with a gas mask. I believe there's a thread to be opened about them.

Not all filter cartridges will stop whatever you are doing.
Filter paper and activated charcoal are good if you are going to be working with airborne particles. It WONT protect you against most gasses.
Someone with a good knowledge of filter cartridges should write a little something that we could all refer too.
I have a bunch of filters: some for small particles, some for solvents (given to painters) but it is the military grade I use more often.
I should be said that many of these cartridges "wear out". They might be used long after their expiry date but once "open" they cant be kept forever even if you dont use them.

JJay - 2-3-2016 at 14:27

I do use a gas mask from time to time. Your ventilation should generally be sufficient so that the gas mask is only a backup for emergencies. Of course, you don't want to feel a draft from a passing gale and accidentally catch a whiff of the fresh batch of hydrazine that you are whipping up because you didn't feel like wearing your gas mask. But if you have to wear it all the time, you really just don't have adequate ventillation.

welshwing - 2-3-2016 at 15:59

What is so bad about butane? "Bunsen burners" that use butane say they can reach up to 2000 degrees F

[Edited on 3-3-2016 by welshwing]

Herr Haber - 2-3-2016 at 16:01

Maybe... but we dont all have a fume Hood.
I have a 385 cubic /meter / hour extraction with the inlet that I can move pretty much anywhere I want on my workspace and the outlet is connected to the air intake (in this case it's the outtake) of the kitchen thought some plasiticized aluminum.
But still, as a precaution I wear a gas mask on many occasion. Mostly because if havent gotten a full face shield yet but also because some nasties will beat the extractor (was making Chloropicrin last week, I'm stil perfecting the process because my yields are poor).
This is one of the cases, extraction or not (I cant build a real fume Hood there: it's my kitchen!) a gas mask is truly usefull :)