Synthesizing bromine

[jgmotamedi]

Has anyone made their own bromine?

Last week I stopped by the local lab supply in Portland, OR, and was quoted $375 for 100ml of bromine. Wow, I was floored. The majority of the cost is transportation, since it has to come in by truck as the regular carriers (FedEx, UPS, USPS, et cetera) won’t carry it. Last time I bought bromine I was able to buy it “over the counter” for about $.50 a ml with no additional shipping costs.

So rather then spend an absurd sum of money and fill out all sorts of government forms, I thought it would be easier to synthesize my own bromine. A few years ago, I made a small amount (~2ml) of bromine by electrolysis of a KBr solution, but this was very inefficient. I thought a better method would be to replace the Br- in a KBr or NaBr solution with Cl-, using Cl gas. Since the bromine has limited solubility in water, most will settle on the bottom of the beaker, where I can carefully remove it by pipette or separatory funnel. If necessary, I could also purify the resultant bromine by distillation.

I did a quick web search and located a few online science forums where this method is outlined, one of which even suggests that you can get all the chemicals you need at a pool supply store, using NaBr, HCl, and calcium hydrochloride. Since I actually have all of these chemicals and a lab-grade fume hood, I thought I would give it a try.

Does any one have a better method? Any ideas, comments, or sources?

[Mercury]

No better method, ideas, or sources. Just a comment:

Welcome! You’re in Portland, I’m in Seattle. Nice to have someone local to talk to. Who the heck are you?

I’m not a chemist at this (or any) level. I’m still working on the supply of Br that I was fortunate enough to buy many years ago. It is now stored in Teflon bottles (so they couldn’t break like glass), but even they seem to transpire and I’d like to go back to glass with a screw cap that is impervious to Br. I’m looking for a supplier, hopefully that will sell in less than “case quantity” i.e. 24 500 ml bottles. I need two, maybe three.

Dumb chemist wannabe question… by passing a more reactive gas like chlorine through a bromine-salt solution, will that cause free bromine to “precipitate” out of solution, or will the bromine be driven off as an evaporate since it is also so volatile?

Sorry, I hope I’m not wasting your time.

Ken Nelson

[Andy Stockton]

Hi Jason – I encountered the same problems you found with the purchase of bromine – the chemical was fairly cheap, the shipping was the killer. I haven’t researched synthesizing bromine yet, but have spent a fair amount of time looking up synthesizing iodine crystals as I plan to try that at some point. One surprising source for that info was YouTube. I spent a moment searching bromine just now and came up with this http://www.youtube.com/watch?v=hbBVgufI9y4 – there are other videos on bromine listed, so you might want to have a look there.

I will be very interested in following your experiments. The main thing that has concerned me in “rolling my own” daguerreian chemicals (after safety) is whether I will be able to achieve adequate levels of purity in a home setting. Some of the iodine precipitation methods looked like you could end up with undesired halogens or acid contamination in your product. I found a process using KI that looks fairly straightforward and wont require methods that are precise beyond my “home lab” capabilities, but still wonder if the I2 I produce will have hidden flaws..

I know we have several members who are professionally trained in the sciences, so I hope they will chime in to help us stay safe and yet have good results. The difficulty of obtaining the required chemicals is yet another barrier to daguerreian practice that is likely to continue or even get worse in the future. Having information about alternatives will help everyone.

[jgmotamedi]

Thanks for the responses.

Ken, I didn’t know you were in Seattle. Although you don’t know it, I am indebted to you. Your 1977 manual–along with Levi Hill, SD Humphrey, and advice from Irv–was my guide to mercury developed plates and remains an important reference for me. So belated thanks. I get up to Seattle with some frequency for work, so perhaps we can meet there sometime.

The idea is that most of the bromine, once it saturates the K/NaBr solution, will settle below the solution. I assume there will be some loss to vapor, but I am guessing that the pressure of the solution will hold most of the bromine in liquid form.

Andy, I don’t know about how pure the bromine must be. Does a bit of water in it change its reactivity? According to a few posts on various online forum you can remove most of the water by stirring in some concentrated sulfuric acid. The acid doesn’t react with the bromine and absorbs the water. Of course, an easier method might be to simply distill the bromine, which if done at a low enough temperature should remove the water and any other impurities. I haven’t thought about iodine, since it is still pretty easy to buy. Mercury also seems to be relatively easy to purchase, but I have enough of that to last a lifetime (and cut my lifetime significantly shorter).

Before I do this, does anyone have a good source for bromine?

best regards

jason greenberg motamedi

[Andy Stockton]

Hey Jason-

You may find iodine progressively more difficult to get in the USA. The DEA has made crystalline iodine a regulated list 1 chemical (pertinent info to be found at this link: http://www.deadiversion.usdoj.gov/fed_regs/rules/2007/fr0702.htm ).

Small retailers have virtually stopped carrying it because of the reporting requirements (the DEA must be sent information about the identity of every person buying the product). You can still find it on eBay, but those sellers are all in violation of the law at present if they are not collecting the required DEA info, and have registered with the DEA as a seller.

eBay sources also have the same problem they have always had – how good is the product?

So you may even find the eBay sellers choked off eventually, that is why I have put the time into investigating how to synthesize I2 from chemicals that (at this point anyway) are not controlled.

I personally think that the DEA’s approach to controlling methamphetamine production by controlling precursor chemicals is silly, but they didn’t ask me. I just hope somebody doesn’t let them know that drugs are made out of atoms, or they will pass regulations controlling those too.

But we must forge on somehow if we are to have our art.

[drdag]

Hi Jason

I have bought bromine water, (fairly easy to get). I am lucky enough to have some phials of bromine (that I got from a dodgy mercury supplier) to ‘top it up’

(I am Brenton who you helped/inspired a while back)

[jgmotamedi]

Hi Brenton, nice to meet again! I have never used bromine water, although I suppose there is no reason I couldn’t try.

It seems that nearly anything can be used to make meth. In any case, I will also look into making iodine, although for the moment I have more than enough. Did you have a method in mind Andy?

For what ever it is worth, I stopped by Alaskan Copper and Brass this afternoon (a major manufacturer and distributor of metals, at least on the left coast of the US), looking into new sources of copper. While they didn’t have any of the old mirror finish copper I used to use, their prices for a 36″x96″ sheet of .04″ copper with a milled finish was $240, and 18 gauge brass was $175. That seems pretty cheap, and would make quite a few plates. They had remnants too, which were very cheap, but in odd sizes and a bit banged up. Of course, the problem is they won’t cut to size (anybody know a cheap source of plate guillotines?) and the milled finish will take a lot of work to get to a nice polish.

[Andy Stockton]

Hi Jason-

Re making Iodine – this video displays the recipe I found that seems to use the fewest chemicals:

http://video.aol.com/video-detail/how-to-make-iodineelement/3683647584

but it creates a number of reaction by-products that may or may not be problematic. I am told the reaction equations are as follows:

“Re: Potassium Iodide + Conc Sulphuric Acid

NaI + H2SO4 –> HI + NaHSO4

8HI + H2SO4 –> 4I2 + H2S + 4H2O

6HI + H2SO4 –> 3I2 + S + 4H2O

2HI + H2SO4 –> I2 + SO2 + 2H2O

You get a bit of HI (steamy white fumes in moist air) but not a usable amount. You also get violet iodine vapour. You get some yellow solid due to sulphur forming. You get the smell of bad eggs from hydrogen sulphide. You also get a brown sludgy solution, due to the tri-iodide forming.” (From http://www.thestudentroom.co.uk/showthread.php?t=396437 )

There are recipes that require more ingredients, but may result in fewer unwanted by-products.

Here is a video of one such:

http://www.youtube.com/watch?v=CLhwkFKLdPA

and a link to the recipe http://www.homechemlab.com/iodine.html

I have no idea if the by-products in the first reaction can be removed by rinsing with water or what problems they would cause. Sulfur compounds contribute to the tarnishing of silver for instance, there may be other issues. One article I read suggested melting the iodine into a block to purify it.

As you can see this is a work in progress. It has been a very long time since I have been in a chem lab and I am not professionally trained in chemistry. As a result I proceed very slowly with these sorts of experiments, reading up until I am sure enough of my knowledge that I am willing to risk an actual experiment.

[jgmotamedi]

I too would worry about the sulfur in the solution and prefer the you-tube solution you posted which uses KI with H2O2 and HCl. Like the bromine synthesis above, this would replace the I- in KI solution with Cl-, and precipitate out the I2. I guess that this would produce KI, I2, Cl2, and water. Since I2 has limited solubility in water, you should be able to filter it, and wash a few times with distilled water then filter and dry. You could also sublimate it to further purify it, but I am not sure that would be necessary. One warning however, that H2O2 plus any sort of acid makes a very exothermic (HOT!) reaction which could be dangerous. Using concentrated HCl or H202 could be dangerous, so use diluted chemicals or easier yet, use hardware store muriatic acid (~30% HCl) and the 3% (?) hydrogen peroxide from a drug store. In any case, be absolutely sure that you never directly mix the hydrogen peroxide with the acid.

A big caveat, I also am not a chemist…. Are there any chemists on board? I usually ask a friend to go over reactions with me.

[jdanforth]

Jason, there’s a place in Portland called TechShop that will almost certainly have a plate guillotine. I am a member of the club here in Durham, NC and they have all kinds of awesome tools for working metal (and wood, etc.). edit: http://www.portlandtechshop.com/

[jgmotamedi]

Thanks, I have heard about the TechShop and will look into it.

[jgmotamedi]

This past weekend I tried to synthesize bromine using the NaBr, muriatic acid, and calcium hypochloride method mentioned in my first post. It clearly produced bromine water as well as a few mls of bromine on the bottom of the flask, but it was not a clean reaction. The calcium hypochloride did not dissolve well into water, and reacted with the muriatic acid to produce a good amount of white precipate, perhaps CaCl? Anyhow, I will abandon this route as the precipitate is too difficult to effectively filter, and I realize now that removing water from bromine is not as easy as I thought. I really don’t want to distill it nor buy a distillation set. I may try to bubble Cl gas through a saturated NaBr solution this weekend, if I can figure out an effective way of producing the gas in one beaker and then bubbling it through another solution.

[botticelli1972]

Has anyone tried crushed up bromine hot tub/swimming pool tablets? They are super easy to get. The ingredients listed on the package list only bromine and an inert carrier.-Larry

[jgmotamedi]

It is an interesting question, and one I have been thinking about. There are two catagories of bromine tablets, BCDMH and DBDMH. Apparently it is possible to extract the bromine from these compounds using KBr or NaBr and sulfuric acid. One possible complication is that BCDMH contains quite a bit of chlorine, and in the extraction process will also produce ClBr, which may be difficult to remove. On the other hand, as another halogen this may actually be an positive addition to the process, although one which may be hard to quantify and reproduce.

I am currently working on extracting Br using NaBr, KBrO3(Potassium Bromate), and sulfuric acid. If this works, I will also try using one of pool bromine tablets in place of the KBrO3.

[jgmotamedi]

Success!

 

I made about 2 milliliters of bromine this afternoon in a fairly simple syntheses.

 

5ml potassium bromide (KBr) were dissolved in 6ml of distilled water. To this I slowly–drop by drop–added 2.5ml of concentrated sulfuric acid (H2SO4). Things heated up a bit, although no other notable changes. I then slowly added–seemingly grain by grain–1.5g of potassium bromate (KBrO3). As soon as the first grain hit the whole solution started to turn orange. After about half was added dark blobs of bromine started to form on the bottom of the beaker. It was hard to get everything to dissolve, but eventually it did. I washed the bromine a few times with a bit of distilled water, and then poured a bit of H2SO4 on top, to dry the bromine. I have attached an image of the product with a bit of H2SO4 on top.

 

Over all it was pretty easy. I don’t think there is enough br for me to charge my box, so I will probably try this again, perhaps tomorrow, doubling the amounts. I will update with better instructions as I can.

 

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[Andy Stockton]

Excellent. Keep us posted on the performance of your “homemade” when you use it.

[drdag]

Crumbs , you are clever, you will be splitting the atom next!

[jgmotamedi]

Thanks.

I ran the synthesis again last night, and now have about 8ml of bromine. If I run it again with doubled amounts I should have enough to create my quick, as well as recharge it a few times. I will certainly write up the experiment, which is really quite easy. All it takes is a fumehood, a bit of glassware, and patience. Things any Daguerreotypist should have at hand.

A more relevant question right now is how do people store their bromine? Ken Nelson and I have been going back and forth about this. I previously had been storing my bromine in glass bottles with poly-seal (polypropylene) caps sealed with Teflon tape. Ken saved me by telling me that this is not safe, since the bromine can easily eat through the polypropylene. I switched to a glass bottle with a Teflon liner, although it still has a polypropylene foam underneath the liner. The caps are green melamine. I have never been completely happy with these bottles, as I know they don’t develop the tight seal I would like.

As I see it my choices are glass bottles with

phenolic, melamine or polypropylene caps

PTFE liner on polypropylene foam or PTFE liner on white rubber

There are also glass “reagent” bottles with PTFE stoppers. Any advice on bottles? I suppose I could order one of those PTFE bottles on Ebay but I am not sure about their quality.

[Andy Stockton]

Here is a link to the best (most complete) plastic physical properties chart I have run across:

http://k-mac-plastics.net/chemical-large.htm

It may be of some use.

The bromine I ordered (which my supplier got from Spectrum Chemicals) came in a brown glass bottle that has a clear plastic overcoating to help protect it from breakage. I have never opened the bottle, but presume it has a plastic cap with a PTFE liner. The cap is sealed in place with blue heat shrink tape. This bottle was purchased in April 2009 and the seal is still intact. Maybe Spectrum Chemicals would tell you what they use.

I had recommended PTFE bottles in the past (based on reading, not experience) but at least two members using them have noted that the bottles are gradually turning pink – probably not a good sign.

[jgmotamedi]

Thanks Andy,

the chart and image are helpful. I have been looking into PTFE bottles, and see that there are different kinds of PTFE, of which ETFE appears to be less resistant to bromine than FEP or PFA. Here is an example of an all PFA bottle and here is a FEP bottle with ETFE cap. Lots of choices, but I am tempted to stick with glass.

[Mercury]

Hello all,

I think the bottles labeled “Poly-Seal” (Wheaton) have a Polyethylene cone liner, not polypropylene. Polyethylene has poor resistance to halogens and other strong oxidizers. I use wide-mouth quart amber jars with a PTFE-lined polypropylene cap. They work great for things like diluted quicks. I haven’t tried, and won’t try them for pure bromine. PTFE lined phenolic would probably be my choice for a narrow-mouth glass bottle for the reagent.

I’ve been storing bromine and iodine monochloride reagents in Teflon bottles with FEP caps for over ten years now. They seem to be doing OK, seal wise, but I have noticed that a certain tiny amount of transpiration is taking place through the bottle walls. For instance, I had a white plastic tape label on the bromine that I had to remove after about 5 years. The adhesive side was yellow and smelled fairly strongly of bromine. Tough stuff!

Andy, do everything you can to keep that bromine in the original bottle and cap! Then save it for when you start making your own.

Ken

[photolytic]

Do not trust the bromine reagent bottles from Alfa Aesar!!!

After more than 4o years of using bromine obtained from Fisher Scientific, I decided to buy some from Alfa Aesar. Since I hadn’t quite finished up all the Fisher bromine, I left the Alfa Aesar Bromine sealed in its vermiculite filled tin shipping can for almost a year. Corrosion began to appear on the outside of the can so I decided to inspect the contents. Upon opening the can I discovered that the top of the plastic bottle cap had been eaten away by the bromine and vermiculite packing was saturated with bromine fumes. Luckily I had saved my old bromine bottle from Fisher and was able to transfer the new Bromine to the old bottle where it remains safely sealed after more than 5 years

[Andy Stockton]

Thanks for the warning about Alfa Aesar. I have it stored in a locked container outside of any living space and the storage space is vented. I have been inspecting it monthly, but think I will step up my frequency. I will watch these storage discussions with more interest.

What are the characteristics of the bromine bottle from Fisher Scientific?

[Andy Stockton]

A while ago I bought some pure PTFE bottles from a place called Structure Probe, Inc.

 

Catalog # 0233-AB Pure Virgin PTFE Jar 15 ml $10.82 and

Catalog # 01963-AB PTFE Dropping Bottle for Laboratory Use 25 ml $36.63

I got them to test but have not done so because I have no need of the bromine yet. I don’t know if they will “weep” but they seem much thicker than the clear looking PFA and FEP bottles. Those would make me very nervous. People have been handling chemicals safely in glass for a very long time. Our use of bromine is such that it involves relatively infrequent handling, so I lean toward glass too.

 

The SPI URL is http://www.2spi.com

PTFE Labware is here: http://www.2spi.com/catalog/plasticware/PTFE-labware.html

 

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[Mercury]

Here here, Andy. I just found similar pure PTFE thick-walled bottles from Cole-Parmer. They offer both a narrow and wide-mouth bottle, pure PTFE caps included. The root Cole-Parmer cat no.’s are: SF-06300 and SF-06200, They are available in a wide capacity range. Spendy little suckers, but it might be the next generation. These have thick enough walls that I don’t think weeping will be an issue for a VERY long time, if ever.

I’m with Andy about glass bottles, it’s the CAPS that are the weak link. It may not be long before the molded PTFE caps for the above bottles are available separately for use on glass bottles? Hope springs eternal. A cap springs a leak.

[Author]

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