Xenon1898
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Recycling Hg from Flourescent Light Bulbs?
Could the 4-5 mg of Hg vapor in flourescent light bulbs be captured effectively in some kind of homeamde reactor? When I throw these out I can't help
but consider that there is Hg going into the environment and what a shame it can't be captured for some home chemistry activities. Yes I know that
the bulbs are supposed to go to special recycling land fills, but apparently only about 2% of the light bulbs actually do, so 98% must be going out in
the trash. Governmen to our rescue. Not the point here... I don't want to debate the environmental policies...
What would be a viable method for this for the home chemist? Assuming we are mostly using our own discarded bulbs then we are probably talking about
a small batch reactor setup which could be sealed, with maybe some sulfur in the bottom, then the light bulbs broken and the Hg vapor allowed to react
inside for however long it takes. The HgS could then be separated from the other glass pcs and junk for subsequent purification. Any ideas on this,
both for the batch reactor and for the purification steps?
I wanted to avoid any kind of continuous air flow because 1)I don't have a fume hood yet and I don't want to give my neighbors a show, 2) any
scrubbing of gasses would waste valueable resources (e.g. Hg in a filter or somthing) and create an additional disposal issue.
[Edited on 3-2-2013 by Xenon1898]
“If we knew what it was we were doing, it would not be called research, would it?”
-Albert Einstein
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Endimion17
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It's out of the reach for us, and you won't save anything by messing with few lightbulbs in a decade.
Don't worry, as they become more and more common, recycling plants will spring up quickly. Every time there's profit involved, people do stuff on a
larger scale.
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Nickbb
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I wouldn't think this would feasible for any home chemist to do really. If there are 4-5mg of mercury in each bulb, you would need to collect mercury
from over 2500 bulbs to get 1 ml of mercury if you manage to get 100% of it out. 1ml of mercury is not worth all that work.
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hyfalcon
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Couldn't sulfur be used in some way to scavenge the mercury out of these bulbs before putting them in the waste stream? Then just cook the sulfur
down and reclaim any captured mercury. Just thinking on the fly.
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blogfast25
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Recycling saver bulbs would be MARGINALLY more interesting to recover the phosphors. But it to requires extraordinary amounts of precessing for very
small yields.
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smaerd
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I busted open one of those small bulbs thinking I'd find a little drop of mercury or something. No such luck, nothing was visible let alone
collectible. I think special recycling programs take them though.
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hyfalcon
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There's only enough to ionize and make a vapor in the bulb. You would have to process many bulbs to get a drop out of it.
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tubelectric
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Doesn't most mercury get absorbed into the phosphor? At least that's how it was said in Wikipedia or somewhere...
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GammaFunction
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Interestingly, opening these bulbs is probably more hazardous than dealing with a broken thermometer, because the Hg is instantly emitted as a vapor.
Source.
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violet sin
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I live in an area where MANY people grow indoor "gardens" and the local garden shops have fairly large piles of HPS grow bulbs. They only recycle
them a couple times a year. A while bac while broke as he'll and bored I picked up a bunch to mess around with. I wouldn't Reccomend doing the same
cause its a lot of work. But I suited up in a jumpsuit, goggles, respirator and 2 layers of gloves and proceeded to break open the outter bulbs and
snipped off the fused alumina(or whatever) inner bulbs. Some were broke. And on a misty evening you could hear the sodium reacting with wAter in the
air. Kinda cool. Any how they had a lot more mercury to mess with. I haven't found a convienient way of dealing with extracting the metals yet so
they are still on a shelf somewhere. Sealed of course. I just point this out b/c if you are gonna go breaking lights open you are gonna want more
than your house provides and better quantities of Hg. It is hours of work but I went thru 300 or more bulbs in a few sittings. The tubes I figured I
could use for other experiments and there were some other components in there that looked interesting like little "getter" strips. Prob was it can be
hard to track down the info on composition of the components. So if you still wanna do Hg recovery look there but be ready for hours of monotony And
the responsibility of properly disposing of the waste. I mean they were headed for a hazmat Truck after all and still may end up there if I can't
figure out a procedure To get my TINY TINY prize from them. Just food for thought. Edit*. Forgot to mention in tha t huge pile I came across maybe 8
metal halide bulbs and each one had several whole drops of metallic Hg rolling around in there but I was warned by a laser service tec that some of
the halide salts would make ya quite sick if you got any in a cut. Original idea was to use the tubes for a Brewster windowed lazing tube. Turned
out to be nothing short of fantasy that I might pull that off though! Live and learn, but at least dream big I guess 
[Edited on 5-2-2013 by violet sin]
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Xenon1898
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wow
Breaking all those bulbs down... sounds like work! It is entirely possible that doing all that work would expose one to too much of a
cutting/exposure hazard to make it worth it, except as a one time learning project.
I was not thinking this would be a valuable source of Hg, but rather if a home owner piled them up over the years then maybe it would be a fun little
project to attempt it in one single batch as a challenge to see what yield could be had (for the chemistry challenge, not for the gallons of Hg you're
never going to get). Not like some kind of major assembly line where you are cranking through thousands of bulbs to get half a drop of impure Hg.
That's what the recyclers do.
One day Hg will be totally banned, we are getting closer every day. I just hate the trend of banning something like liquid Hg in products, then the
government turns around and pushes it into every household where many innocent people will get exposed to breathing the vapors when they sweep/vacuum
up the broken bulbs. So the other reason is I was just brainstorming on alternate sources, however tiny weeny it may be.
If I wanted to crank out some Hg I would just find a source of cinnabar... somewhere... (no idea where though)
“If we knew what it was we were doing, it would not be called research, would it?”
-Albert Einstein
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Nickbb
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People really overrate the dangers of mercury. They act like if you break 1 CFL bulb you need a huge HAZMAT team to decontaminate the entire house.
They only contain 5mg of mercury for crying out loud! That might kill a couple brain cells, but not enough to do any real damage. The funny thing is
is that they try to protect people from dumb garbage like that, but hardly do anything when it comes to alcohol and cigarettes and the millions of
people it has killed. How ironic.
Anyhow, if you put enough effort into it and acquire enough light bulbs, you can get some mercury. Right now if you want mercury you can either order
it or get it out of old thermometers, barometers, or sphygmomanometer. What would really be fun is to actually get some cinnabar out of an old mine
and get mercury from that. I actually saw a sample of cinnabar in a gift store in Arizona... I almost bought it but settled on a rock that had a lot
of copper ore (it is a pretty cool looking rock with blue veins all through it)
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