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Poppy
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Quote: Originally posted by blogfast25  | | Nice! With freshly prepared PbO2 you can make the interesting salt (NH4)2PbCl6 (ammonium hexachloroplumbate) which no one here seems to have attempted
yet. Adding chilled conc. H2SO4 to it liberates PbCl4 as a dark, heavy, oily liquid. |
Do you have a note on how long PbCl4 survives hermetically without overwhelming the jar?
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blogfast25
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AF Holleman claims that at room temperature it slowly decomposes to PbCl2 and Cl2.
I carried out my own synthesis of (NH4)2PbCl6 yesterday, this one starting from Pb(NO3)2 (oxidising it to PbO2 with thin bleach in very alkaline
solution). Although I obtained the salt, yield was lower than expected because when I dissolved the PbO2 in conc. HCl (iced) quite a bit of white
precipitate formed. This is due to partial oxidation of the HCl to chlorine (which I could smell) by the PbO2, I believe :
PbO2 + 4 HCl == > PbCl2 + Cl2 +2 H2O
If I find time this afternoon I might adapt the addition procedure to minimise this loss to PbCl2.
[Edited on 30-3-2013 by blogfast25]
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blogfast25
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An attempt at adding ice cold conc. HCl drop by drop from a 10 ml burette onto an iced, concentrated slurry (in water) of PbO2 didn't improve yield of
dissolved PbCl4 (as PbCl6(2-)) by much. Right from the start chlorine gas evolution could be smelled and at the end of the addition some white
precipitate (PbCl2) was obtained. Subjectively I'd say yield of dissolved PbCl4 was about the sme as during the first experiment.
Also very subjectively I'd say about 30 % of the initial PbO2 is lost to PbCl2.
[Edited on 1-4-2013 by blogfast25]
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KernelPicnic
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Off topic, but yesterday I made about 30g of lead bromide. Apparently, the stuff is pretty light sensitive. When I finished drying the product, I
noticed the powder adhering to the filter paper had turned dark grey. I also left the bottle near a window overnight and a thin layer had turned
black. Kind of interesting since the chloride is not photosensitive at all.
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blogfast25
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Lead bromide isn't known for being light sensitive, as far as I know. How did you prepare it? Is it possible that it's contaminated with silver
bromide?
[Edited on 3-4-2013 by blogfast25]
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KernelPicnic
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| Quote: Originally posted by blogfast25 | Lead bromide isn't known for being light sensitive, as far as I know. How did you prepare it? Is it possible that it's contaminated with silver
bromide?
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I used lead nitrate prepared by dissolving roofing lead in nitric acid, and supposedly 99% sodium bromide for use in spas. Mixed stoichiometric
quantities of the solutions, filtered and washed. I highly doubt there is any silver in the product.
I actually made silver bromide the same day. It's a really nice yellow color, but it starts to turn black literally as soon as it is exposed to
sunlight. I could smell a bit of bromine being evolved as it decomposed.
[Edited on 3-4-2013 by KernelPicnic]
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papaya
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I want to report about the experiment i did today.
I was looking for a convenient way of lead salts preparation from metal by electrolysis with lead anode and tried different electrolytes described
here (NaCL, NaHCO3 + NaNO3, etc.) and inevitably every time I had different problems: PbO2 formation, lots of lead deposition on cathode, anode being
covered with a hard crust of white stuff (carbonate?) and other things..
During experiments at last I discovered accidently, that if boric acid is dissolved in tap water (no proportins measured) used for electrolite,
there's a very little current flow at 15V, BUT anode stays clear (no crust), instead, some white ''smoke'' - milky color goes off the electrode and
precipitates at the bottom. To improve conductivity I added a little NaHCO3 to boric acid solution and now it goes faster - lots of white precipitate
already formed, anode is not perfectly clear, but there's no such a thing like hard/insoluble crust or PbO2 formation(no brown color obsereved
anywhere). In short - I'm suggesting to try borax in water electrolyte (i don't have to try myself) and find out if it will work similarly to boric
acid/bicarbonate mix or even better (at least what I have now is much better than nitrate way I tried). Thanks.
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Steve_hi
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Lead?
I tryed to make aome lead acetate which turned out to be a total failure so I roasted it in a ss cup and it first turned a grey colour and I left it
over th flame and it melted again and turned into more of a brown colour WHAT IS IT???
[img]C:\Users\Steve\Desktop\MAY02\New folder\2.jpg[/img]
[img]C:\Users\Steve\Desktop\MAY02\New folder\3.jpg[/img]
[img]C:\Users\Steve\Desktop\MAY02\New folder\1.jpg[/img]
  
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blogfast25
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What exactly do you call 'failure'? How did you try and make the Pb (II) (OAc)2?
Your end product is likely to be a mixture of substances rather than just one single compound. Try some reactions with it: does itissolve in water or
acids to any appreciable degree for instance? Do you observe any effervescence in contact with acids?
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Steve_hi
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I used H202 lead and vinegar. it hardened like a hockey puck when i let it dry. and was a very dark brown.
Any ways as sugested by plant1999 I put it back on the fire and this is the result yellowish green with definite yellow flakes mixed in.
[img]C:\Users\Steve\Desktop\MAY02\New folder\001.jpg[/img]
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papaya
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Sorry if this was asked before, but would molten lead react with molten sulfur FAST enough to provide an alternative way to lead salts preparation?
PbS then probably can be digested by acids to yield desired product (or even be oxidized to PbSO4 somehow?)
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testimento
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I would like to note that I made some lead acetate recently out of curiosity. I had 20kg of car battery junk, which I first heated to 600C to
decompose the PbO2 into PbO and then I powderized the residue and mixed it good with a bucket of vinegar, brought the solution to boil for 10 minutes
and let it stand overnight, filtered it into clear, colorless liquor which I evaporated. White, moist crystals with acetic-like sweetish smell were
left.
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papaya
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I mean while it takes too long to oxidize molten lead in air, sulfur might do it faster, though I'm not sure if PbS is soluble in acids like acetic or
nitric for example, any thoughts?
[Edited on 10-10-2013 by papaya]
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papaya
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Three articles on galena ore nitric acid processing
https://www.sciencedirect.com/science/article/pii/S0304386X1...
https://www.sciencedirect.com/science/article/pii/S0304386X0...
and the last - most positive one.
http://www.tandfonline.com/doi/abs/10.1080/12269328.1999.105...
Only abstract is available, but it's interesting:
"ABSTRACT
Galena, lead sulfide, is leached with nitric acid in order to prepare higher value-added products such as lead nitrate, lead carbonate, lead basic
carbonate, etc. Leaching behavior has varied with the concentration of nitric acid. At the lower concentration of nitric acid, galena is dissolved
into lead nitrate and hydrogen sulfide. However, at the higher concentration of nitric acid, galena is not dissolved but it is changed into lead
sulfate as precipitate. The leaching efficiency is strongly dependent upon temperature and nitric acid concentration. The optimal conditions are found
to be 40°C and 4–8 N nitric acid where about 95% of lead can be dissolved from lead sulfide."
[Edited on 10-10-2013 by papaya]
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testimento
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Oh yes, this is really painstaking task. Although, if you have the capability to heat the lead over 600C and blow air through SS tube, which is
pre-heated to 600-900C, it will oxidize the lead quite nicely. You must remember though, the amount of air required is quite nasty, from one m3 you
can get only about 0.25kg of oxygen. In this case, especially if you have easy access to nitrates, it'd be a worthwhile task to go through the
nitration process. At least this method produces high quality PbO.
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papaya
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Thanks for reply, but I wanted to hear opinions especially about Pb->PbS->Pb(NO3)2 (or acetate for ex.) conversion route - sulfur is relatively
cheap and it MAY be fast.
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Bezaleel
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Pyromorphite
I was reading on the lab synthesis of pyromorphite, Pb5(PO4)3Cl, or 3Pb3(PO4)2∙PbCl2.
The synthesis can be carried out by combining equivalent volumes of the following solutions: 0.026M K2HPO4, 0.044M Pb(NO3)2 and 0.009M KCl. (J. Flis
et al. / Geochimica et Cosmochimica Acta 75 (2011) 1858–1868)
Next, larger crystals can be grown in liquid CsCl between 900C and 500C, under an inert (nitrogen) atmosphere. The pyromorphite concentration used was
1.0-3.0M%, and they used a platinum crucible. (Journal of Crystal Growth 292 (2006) 129–135)
The questions I have about this article is why they didn't heat up to the melting point of pyromorphite (1005C, Arch oral Biol. Vol. 15, pp. 469-480,
1970; was this article incorrect about the melting point?).
Also, I do not see what's so special about CsCl, that you wouldn't use a cheaper alkali chloride (Na, K)Cl?
Finally, I'd like to know where you can find solubility data for Pb5(PO4)3Cl in molten salts? And where can you find melting points for compounds like
pyromorphite? (I spent 4 hours searching articles with Google Scholar, but only one result, which seems to contradict the crystal growth article.  )
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TurboZfreak
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Lead Nitrate Question
Quick question about lead nitrate synthesis. I have been using WFNA diluted down to 68%+/-. I have been using 2 to 1 acid solution to lead. Then
heating the mix to around 85C. After reaction is all complete, I use 10 times the volume in distilled water to dissolve the nitrate salts, then filter
it. I then take the filtered solution and heat it to 95C and let it steam off. So far works great, I am getting great yields. But what is the best
process for neutralizing the crystals? If I wash them, then I have to go through the boiling them down again.... I cant find a good reference to this
from well over 2 hours of googling... Right now I have over 100g of white fuming lead nitrate... lol. Can I use a sodium bicarb solution to neutralize
the crystals? I know I will have to re-boil them down, but I was not sure about the purity of the nitrate crystals when the water evaporates off.
Would the bicarb be left over as well?
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Ral123
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What an abomination. Be gone from this world.
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TurboZfreak
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OK....
what the hell was the flame for??? I have a shit ton of WFNA. I can make it easy and cheap. Why go pay a bunch of money for 68% Aqueous NA.
[Edited on 3-5-2014 by TurboZfreak]
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Dornier 335A
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Are you sure the crystals are acidic? Adding sodium bicarbonate would leave you with an impurity of sodium nitrate and bicarbonate. A better solution
is to neutralize a concentrated solution of your lead nitrate with lead carbonate, filter to remove excess carbonate and then evaporate the solution.
Don't take Ral123's comment personal. Diluting WFNA is likely seen as some sort of crime in this subforum because it's the most useful reagent of them
all.
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TurboZfreak
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Thank you for good input.
YES, 100% they are acidic. They give off a STRONG NOx odor as well as when I open the container, white fumes come off. The only conclusion I can come
to is, I am not diluting the acid enough? I cant find a very good guide on lead nitrate synth.
Now as for the lead carbonate, does not look like a very easy acquirement.. Any suggestions on accruing this or another method?
[Edited on 3-5-2014 by TurboZfreak]
[Edited on 3-5-2014 by TurboZfreak]
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Dornier 335A
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It's not about the concentration of your acid, it's whether you have an excess of acid or not.
Lead carbonate should not be too difficult to prepare; it has very low solubility in water.
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sasan
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turbozfreak,the odor of nitrogen oxides from the container is because of hydrolization and after sometime it will get a yellowish brown tint like my
lead nitrate and if you dissolve it in water you'll see a little amount of brownish yellow precipitate(and I think it is mixs of lead oxide,lead
carbonate and lead hydroxy nitrate).
My suggestion is dissolve lead metal in NA and let it evaporate in outside to drive off the excess NA(do not boil down the solution) after complete
drying dissolve the lead nitrate in distilled water and use solution of lead nitrate,if there is little brownish precipitate,add a little NA to solve
it untill you get a clear solution,you can just filtrate the precipitate.
It is a suitable procedure for Pb(NO3)2 Hg(NO3)2 Bi(NO3)3 and some other salts.
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Bert
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| Quote: Originally posted by TurboZfreak | OK....
what the hell was the flame for??? I have a shit ton of WFNA. I can make it easy and cheap. Why go pay a bunch of money for 68% Aqueous NA.
[Edited on 3-5-2014 by TurboZfreak] |
He is being dramatic, WFN is a holy grail to some newer energetic materials enthusiasts.
Thanks for your help with the edit!
Also, you have not read the FAQ regarding posting here... So this goes to "beginnings" now.
| Quote: |
didn't find this thread before posting "Homemade Lead Nitrate" in the chemicals forum. A method to make lead nitrate is there now.
++++++++++++++++++++++++++++++++ Actually, it's HERE now.  NBK
++++++++++++++++++++++++++++++++ HOMEMADE LEAD NITRATE REQUIRED MATERIALS:" OLD AUTO BATTERY NITRIC ACID HYDROCHLORIC ACID Charge old battery to
restore as much active material as possible and drive out as much sulfate from plates as possible. This means overcharge it (but don't make it hot to
the hand) for several hours after cells are bubbling gas a lot. Then pour out the acid (this will be sulfuric at about 25% concentration with some
dissolved lead sulfate in it. It can be poured into the ground but away from where people live. A junk yard in Florida (and lots like it) for 20
years bought about ten car batterys a day, and turned them upside down on the sand in a ditch in front of their yard, to get liquid out of em so he
could transport them to the bigger yard sans liquid. They would not take those withe liquid in them. He put several tons of lead sulfate laden
sulfuric acid in a drainage ditch that was normally dry except in rains. It cause NO visible effects. Grass growed in the ditch, trees grew 4 ft away,
etc. S0, lead sulfate is NOT a major hazard to the environment. The government does not see it that way, so take care. When drained, fill all cells
with water, and charge some more, then pour that out. Repeat that about 3 times, or so, then after the last pour out, fill again with water, and let
sit a day so most acid in plates diffuses out. Again dump all liquid from the battery, and let it stand upside down a day, draining all that will
come out. Then take apart the battery by cutting the top off just above the plates with a saw. Cut the connector posts also when doing this so you
end up with just the plates and post stubs on them, and no top. Pull out the cells by pliers grabbing their cross straps. Seperate them into
negative (gray) and positive(brown). Dispose of the case, tops and cell insulator plates by burial or burning. DO NOT leave them around. They shout
at all persons (This guy took my lead and did something terrible with it). Keep the plates wet to prevent dust problems. Wear waterproof gloves to
protect skin when handling them. Put all brown plates in a plastic bucket, and pound them with a flat stick to knock out most of the brown powder
from the plate grids. Pound the brown stuff in to a coarse powder, but keep it damp so there is NO dust. Do not try to make fine dust, no need, and
its hazardous. To 240 grams of brown dust, add 200 cc Nitric acid, of 50 t0 60 % (or whatever strength you got, just adjust the 200 cc about enough
to compensate for your acid conc. Too much is better than not enough for the brown lead you got. not enough will show brown stuff in your white stuff,
and be hard to seperate, so more acid will have to be added and it done again. OVERDO THE ACID! Put the lead dioxide (brown powder) in a quart of jar
volume for every 240 grams brown powder. Pour the Nitric acid on it. Nothing happens. Might see some white fumes from the acid but no reaction
usually. Pour in 10 cc of pool hydrochloric acid (about 30% stuff), all at once so conc HCL goes down on the powder through the nitric acid. Where
it hits the powder a reaction ought form, (no heat needed). Bubbles of oxygen will come off. Let it sit. No need to stir, and speed up the reaction.
It won't become a runaway, No red fumes or stuff, but it can bubble up and foam. If it's going pokey, stir ONCE and see what that does. Then stir to
suit your desires so long as you don't cause it to get out of your container. NOTICE, THIS LIQUID IS VERY POISONOUS AND WILL CONTAMINATE HELL OUT OF
THE GROUND WITH SOLUBLE LEAD NITRATE. DO KEEP ANOTHER CONTAINER, LIKE A PLASTIC BUCKET UNDER YOUR REACTION VESSLE JUST IN CASE YOU HAVE AN ACCCIDENT.
When all done there will be a white precipitate where the brown powder used to be, and a pale yellow liquid above it. Pour off the liquid, (easy to
do because the lead nitrate is very heavy and does not like to follow the liquid that is flowing out). Work over a containment in case you spill.
You can salvage the liquid by pouring it into an excess of brown powder . When it finishes, heat the liquid and brown powder to dissolve all the
nitrate you can, then pour it off. The liquid will contain lead nitrate, dry it to get the powder. 240 grams brown powder will yield 330 grams lead
nitrate. A car battery has several kilos of brown lead in it. The grey plates are made mostly of lead powder. It's hard to react, so it can be
melted and bullets made of it. What don't melt will be a lead compound which ought react with the weak aqua regia mix above. (NA + tad of HCL) Take
care of the lead nitrate. Being very soluble in water, it can cause peak pollution levels in streams etc which cause monitoring instruments to go
crazy, and launch local nothing-to-do search parties to go find where it entered. Experimenting mad scientists don't need that kind of stuff. Don't
scare hell out of everyone that knows zilch about things, and they will leave you alone. Remember all "monitor" personnel crave attention, worse
than a sub crewman back from a year without seeing light of day, craves sex. So expect them to say wild things about the pollution, and make it
sound like they saved the world from asteroid impact. YO Ass will be their podium while they doin all that. Someone might even start yelling
tarrrrouussst,...damned tarrorist... and you know where it will go from there. Just use your common sense, and don't invite trouble. Be a
responsible experimenter, even if it hurts. To dispose of lead nitrate, with minimum hazard, mix it with sulfur and burn it into lead sulfate + some
lead sulfide (galena) both very insoluble in water, and not capable of a pollution that would sound alarms. Avoid the fumes (stand so wind carries
fumes away from you and toward a wilderness. Not good to send stink into neighbor's window. If he finds out what it came from he could cause a stink
of his own.) 330 grams lead nitrate plus 64 gms sulfur ought burn like a road flare, and stink a lot since sulfur dioxide takes out the excess
oxygen. It would be wise to burn it in a tin can and under ground in a wilderness area, so stink stayed there and the nitrate changed to sulfate
there, and no harm done. It is a crummy grade of black powder level stuff. WASH YOUR HANDS AND FACE BEFORE EATING AFTER FOOLING WITH LEAD CHEMICALS.
Don't want you to die before the government gets to kill you in some economic war to steal more oil. <small>[ August 03, 2002, 05:53 PM:
Message edited by: nbk2000 ]</small>
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[Edited on 4-5-2014 by Bert]
Rapopart’s Rules for critical commentary:
1. Attempt to re-express your target’s position so clearly, vividly and fairly that your target says: “Thanks, I wish I’d thought of putting it
that way.”
2. List any points of agreement (especially if they are not matters of general or widespread agreement).
3. Mention anything you have learned from your target.
4. Only then are you permitted to say so much as a word of rebuttal or criticism.
Anatol Rapoport was a Russian-born American mathematical psychologist (1911-2007).
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