Synthesis of Bromine

[frosch45]

That bottle looks fine. Just as long as it's sealed well.

 

Back to your origional question.

 

I have never tried the electrolysis, but it seems to me that it would be much more difficult. Unless you have an apparatus already set up that is very resistant to corrosion, I think you should use the HCl method. All of the chemicals are readily available in one spot (pool supply store) and it is relatively safe. That will be the easy part though. The purification would be hard. You might use a dessicator or something and distillation (but the volitility of Br is annoying). Anyway, you will definately get impure bromine water either way, unless you are electrolyzing molten NaBr, wich would be very difficult indeed.

 

Just don't get any on your skin.

</gross understatement>

[hermanntrude]

Just don't get any on your skin.

</gross understatement>

 

or in your lungs, eyes, ears, stomach or nose.

 

basically, be very careful

[Tealman535]

That will be the easy part though. The purification would be hard. You might use a dessicator or something and distillation (but the volitility of Br is annoying). Anyway, you will definately get impure bromine water either way

Is there any way I can purify it?

I cannot afford an entire distilling apparatus.

I don't have a retort.

 

Sorry guys, looks like I just can't make bromine at this point, I'll have to wait a few years before I can afford all this.

 

 

Tim Ambrose: Teenage Inventor/Scientist

[frosch45]

Actually, bromine's volitility could help you in this instance. pour your bromine/calcium chloride/HCl mixture into a beaker and let some of the bromine vaporize. Have a test tube in an ice bath waiting, and pour off the heavy vapor into the test tube. This is a pretty crude way of doing it, but if you really wanted to do this, and if you were very patient, you could get several mL.

[YT2095]

Br2 is very heavy and will sink to the bottom as soon as it`s made, it is a simple case of using a pipette to extract this afterwards, it really is an easy chem to work with in that respect.

the ground glass stoppered bottle in the picture is entirely unsuitable for bromine storage, at the very least you need a screw top bottle with a ptfe barrier.

I personally have mine stored in sealed glass vials, and for Lab use I keep it stored as a Br and BrO3 salt mixture, to which I simply add a little sulphuric acid to make instant bromine.

[Tealman535]

the ground glass stoppered bottle in the picture is entirely unsuitable for bromine storage, at the very least you need a screw top bottle with a ptfe barrier.

Could you show me a picture of the type of bottle and Teflon stopper you are describing.

Will something like this do? http://cgi.ebay.com/VOLUMETRIC-FLASK-25mL-25-mL-A-PTFE-Stopper-KIMAX-NEW_W0QQitemZ180207930334QQihZ008QQcategoryZ11812QQrdZ1QQssPageNameZWD1VQQcmdZViewItemQQ_trksidZp1638Q2em118Q2el1247

 

 

Tim Ambrose: Teenage Inventor/Scientist

[jdurg]

Bromine is near impossible to keep in any type of container. Even in a sealed glass ampoule it will weaken the glass and slowly eat through it. My Br2 sample is in a thick glass ampoule embedded in an acrylic resin casting. Over time, if you just keep Br2 in ANY type of openable container, it will leach through it and corrode EVERY metal in the area. (well, EVERY meaning anything you would commonly keep it near. Yes, I know there are some exceptions).

 

It's really amazing how it is the houdini of elements. It WILL find its way out of any openable container you put it in.

[frosch45]

It's really amazing how it is the houdini of elements. It WILL find its way out of any openable container you put it in.

 

I remember before I changed my Br2 into AlBr3 (quite a while ago--I was much more stupid) I did have it in a glass flask with a glass stopper on top. I taped the stopper onto the flask very tightly. Big mistake:rolleyes:

 

Within 48 hours my "lab" stunk really bad. When I checked on the flask, I discovered that not only had the Br2 squeezed by the glass stopper, it had significantly corroded the tape....

 

Then I decided that it wasn't such a good idea to have bromine sitting around.

[YT2095]

I keep mine in the fridge (not the food fridge but the Labs fridge) I also keep the Iodine in there too, it, like Br2, will also escape many forms of confinement, keeping it cold slows this right down.

[frosch45]

I'll go ahead and ask this then.

 

Since you seem to disagree with my thinking about this kind of bottle being ok

 

http://dbhs.wvusd.k12.ca.us/webdocs/...assStopper.JPG

 

and I will not pretend that I know more than you do at this point

 

 

I was wondering what you would suggest YT?

 

I have come across many glass flasks with Polyethylene stoppers. Would this be okay for, say, nitric acid? I am pretty sure that the answer is no.....

 

I was planning on making some nitric acid next week because I am in the very final stages of picking up a distillation apparatus for a good price (unless someone has any places where I could get one for cheaper than $100 US (and that includes the condenser, flasks, and adapters))

 

And I wanted to store it. I am planning on using KNO3 and sulfuric acid, both of which I have.

 

So what do you recommend, not just YT, but anyone with reasonable expierence. I was planning on making somewhere around 500 mL.

 

EDIT:

 

for example, would any of these work?

 

http://cgi.ebay.com/Hand-blown-Wine-Decanter-1000ml-Poland-New-FREE-S-H_W0QQitemZ110166315308QQcmdZViewItem?hash=item110166315308&_trkparms=39%3A1%7C66%3A2%7C65%3A15&_trksid=p3286.c0.m14.l1318

 

http://cgi.ebay.com/Pyrex-1000-ml-Flask-s_W0QQitemZ150237755980QQcmdZViewItem?hash=item150237755980&_trkparms=39%3A1%7C66%3A2%7C65%3A15&_trksid=p3286.c0.m14.l1318

 

http://cgi.ebay.com/Reagent-Bottle-Apothecary-Jar-Chemical-Storage-1000mL_W0QQitemZ190223885314QQcmdZViewItem?hash=item190223885314&_trkparms=39%3A1%7C66%3A2%7C65%3A15&_trksid=p3286.c0.m14.l1318

Edited August 7, 2008 by frosch45

[YT2095]

glass is fine for nitric acid, but it`s best to use brown glass bottles as too much light will decompose the acid over time.

you may find it helpful to add a little carbamide (urea) to the acid after making it, it`ll destroy any NOx contamination.

[frosch45]

i read that in another post by you a while ago when i didn't know much about carbamide. i nearly fell off of my chair laughing, even though after I got a hold of myself i found that you were right

 

I know that glass is fine, and that brown glass bit was helpful, but what I'm mainly concerned with is how to seal it. Is a regular old glass stopper fine? I have never really wanted to buy a $500 lab fridge

[Tealman535]

I still would like to know which of these two is better for keeping bromine?

http://dbhs.wvusd.k12.ca.us/webdocs/AcidBase/Lab-AcidBaseTitration/Bottle-GlassStopper.JPG

or

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWAX:IT&item=180207930334#ebayphotohosting

 

Thanks.

 

 

Tim Ambrose: Teenage Inventor/Scientist

[jdurg]

None of those would be suitable. Br2 would escape out of both of them pretty quickly as they don't provide a tight enough seal for long term storage. If you look at most containers for liquid chemicals, they have screw tops to them to provide a tight seal. If you were forced to pick a container, the first link would work better but you would still lose your bromine pretty quickly.

 

If the rest of the thread hasn't explained it enough yet, bromine is not able to be kept fully contained in a container for lengthy periods of time. It just vaporizes too readily and attacks too many things. If you've ever been in a chemistry supply closet, you'll noticed that the area the Br2 (and less so I2) is stored is typically pretty corroded and "rusty". For a chem lab, it's not too big of a deal since they can always order, or make, more bromine quite easily. For a home chemist, it's not so easy and the time and effort spent making the bromine is pretty extensive.

 

For storage of bromine that you will use in reactions (E.G. not a sample that you want to keep for display), you need an amber glass bottle with a Teflon screw cap. You then need to put the Br2 bottle into a large tin can filled with diatomaceous earth and/or a sodium thiosulfate powder (to soak up a spill if something went wrong). The top of the can should be like that of a paint can where you hammer it shut, then use a screwdriver to pry it open. Store this is a cool area away from things that you don't want getting corroded. The corrosion will be minimized by this storage, but over a period of a few years it will still eat its way out.

 

I actually bought a bottle of bromine a few years ago (probably 50 mL or so) and while the Br2 shipped just fine, within a week it had completely dissolved the Teflon "lined" cap and corroded everything in the area. I was fortunate to have an amber glass bottle left over and quickly transferred it with minimal damage/loss to my stuff and my flesh.

[ChemLabs]

I know that Bromine liquid is volatile and easily escapes most containers. My thought is to keep it in a vial in the freezer or bellow its melting point ( 7 C ). Any other suggestions?

[Mr Skeptic]

In a sealed container, I would think. Just don't then heat your sealed container.