Fusionfire
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Safe disposal/handling of lead in a domestic setting
I am looking to make my own Pb(IV)O<sub>2</sub> MMO anodes for a perchlorate cell.
I have a number of questions regarding the handling/disposal of lead at home.
1) I don't have a purpose built lab/workshop (yet) at home. Should I forget about doing any work in the kitchen?
2) Will soluble lead compounds permanently contaminate plastic, glass or wood surfaces? Would it therefore be wise to cover all worktops with old
newspapers?
3) Should any rags used during the work be disposed of?
4) Where is the best place to throw out unused lead solution? Down the toilet bowl, street gutter, corner in the garden, toilet sink?
I will follow common sense precautions like washing all clothing after the work and precipitating out aqueous lead solutions with a sulphate salt.
I understand there is no safe exposure limit for lead hence my extreme precautions.
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platedish29
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So if you admitedly working in the kitchen, one concludes you working on your house, so one supposes you have access to some bricks with which you
could rise a little furnace. Now, try to synthesize lead oxides from all the lead crap you producing, the main reaction apart of course. Keep this
until you have some kilos then pour it into coal fire to collect molten elemtal lead.
Tip: use your newly built furnace as a host for the reaction
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LanthanumK
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Lead is not the most toxic metal in the world (people have been casting lead bullets and other lead objects for centuries), but chronic exposure is a
concern. A good way to see if significant quantities of soluble lead(II) are present is to spray the surface with an iodide solution. A yellow
precipitate indicates lead. I tried this on one of my washed out vials and it turned out strongly positive.
hibernating...
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AJKOER
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Wash contaminated equipment/areas with a strong base (even ammonia may be OK). Let dry and follow-up :with a good wipe with a damp disposal paper
towel.
Chemistry:
The goal is the insoluble Pb(OH)2 or other insoluble basic salt. See http://www.public.asu.edu/~jpbirk/qual/qualanal/lead.html
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blogfast25
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Don't mess with lead or lead compounds in your kitchen.
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phlogiston
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Chronic exposure to even very, very small amounts of lead have a measurable effect on IQ and memory, especially in children. You can hardly take it
seriously enough. The brain you have now can never be replaced or cured from the effects of lead exposure. Think how you will curse yourself if you
notice a decline in your cognitive functions a few years from now. It certainly isn't worth sacrificing to obtain a little perchlorate. Especially
soluble lead compounds are dangerous.
1. Do not use the kitchen. You will regret it. It is inevitable that you will spill very tiny droplets of solution, even if you are extremely careful.
(Never mind the cleanup nightmare you have to deal with in case of an accidental larger spill). I know from experience using intensely colored
solutions or radioactive solutions that can be easily detected that even if I work with very small amounts and work very carefully, there will still
be (often invisibly) small droplets here and there. You will not notice them and transfer them everywhere through your clothes, hands etc (although
the iodine staining lanthanumK suggested could work). I think such droplets come from small amounts of aerosol when a small bubble bursts in the
solution or when you empty a pipette, etc.
2. Wood: yes definitely. It will absorb the solution. Plastic and glass: probably not. Newspaper will not do at all. Liquid can pass through paper.
Use something with an inpenetratable layer. A layer of plastic foil with newspaper on top would be a good solution. Also, use a tray with edges that
will retain larger spills.
3. You really should take care that it doesn't end up in anyone elses environment either. The sewer is a terrible idea. I can't even begin to express
my horror about suggesting 'a corner in the garden'. Even if you don't care for your own health, consider someone with little kids may buy your house
a few years from now. Where I live, you can simply take anything containing lead and lead compounds to the municipal chemical waste disposal. They
take care of it, for free (if you are not a company), no questions asked. If they do ask, say you took a car battery apart to obtain some lead for
casting and have some stuff left.
The idea to precipitate any soluble lead compounds as insoluble lead sulphate is good. Given its toxicity, even carbonate and hydroxides of lead are
soluble enough that they are not safe.
To be honest, I really think lead and mercury cannot be safely handled at home, unless you build a good fumehood (or glovebox) and even then much
depends on your technique and attention to detail for preventing contamination.
Siorry for the long post, but I really think it is often not taken seriously enough on this forum.
EDIT: White Yeti is right, the sulfide is much less soluble than the sulfate. The carbonate and hydroxide are also less soluble than the sulfate, but
still several millions (!) of times more soluble than the sulfide.
[Edited on 22-11-2012 by phlogiston]
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"If a rocket goes up, who cares where it comes down, that's not my concern said Wernher von Braun" - Tom Lehrer
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White Yeti
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FusionFire, you posts usually do not scare me, but this time you've done it. Precipitating lead as a sulfate salt is a bad idea. It will lull you into
a false sense of security. Lead sulfate still has high enough solubility in water to have some serious effects on you and the environment. Typically,
mercury and lead salts are precipitated as SULFIDES not sulfates. At that point, lead and mercury sulfides are as safe as the ores they came from, so
you can store them in vials for future use or re-use.
I have a nice sample of lead ore, I might post a picture later.
"Ja, Kalzium, das ist alles!" -Otto Loewi
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Poppy
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Okay we are now well aware of the pros and cons of defrutum and sapa. Though thats not easy a hint to ride in, like quitting tobacco or other stuff.
I feel like a murderer
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Poppy
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Okay we are now well aware of the pros and cons of defrutum and sapa. Though thats not easy a hint to ride in, like quitting tobacco or other stuff.
I feel like a murderer
Swamp fishies wouldn't regreat lead intake,
Quote:
"7.2.5 Acceptable daily intake (ADI) and other guideline levels
Provisional maximum tolerable weekly intake of lead:
adults, 3 mg per person or 50 µg/kg body weight;
children 25 µg/kg body weight (FAO/WHO, 1987)."
Unless that lead comes from radiation shielding of some dismantled nuclear plant
[Edited on 11-21-2012 by Poppy]
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Fusionfire
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Quote: Originally posted by phlogiston |
3. You really should take care that it doesn't end up in anyone elses environment either. The sewer is a terrible idea. I can't even begin to express
my horror about suggesting 'a corner in the garden'. Even if you don't care for your own health, consider someone with little kids may buy your house
a few years from now. Where I live, you can simply take anything containing lead and lead compounds to the municipal chemical waste disposal. They
take care of it, for free (if you are not a company), no questions asked. If they do ask, say you took a car battery apart to obtain some lead for
casting and have some stuff left. |
Correct me if I am wrong, but I assumed the lead will wash out of the soil after a few years. Sooner if it is dumped into the sewers.
But yeah, I am beginning to think working with lead at home is always a bad idea. Let's face it, ALL of us are going to get thicker as we grow older.
Who wants it hanging over their conscience, maybe they wouldn't be getting as thick, as quickly, if it weren't for them messing around with lead at
home...
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Fusionfire
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Guys I found this Chinese company that sells PbO2 MMO anodes, specifically for perchlorate production:
http://www.bjchangli.com.cn/productgrouplist-212734861/Pbo2_...
I made an enquiry with them and they tell me:
1) Substrate: Gr2 titanium mesh
2) MMO coating: PbO2, 8-12 microns
Can someone advise if the PbO2 thickness is adequate for a perchlorate cell?
Also, I presume very very small quantities of Pb would dissolve into the cell and taint the electrolyte, perchlorate crystals, etc. Therefore should I
treat the leftover electrolyte as though it has lead contamination, and even the recrystallised perchlorate crystals as such?
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