Hexabromobenzene
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Bromides from plastic
Some plastic contains bromine as brominated flame retardant. It may be polycarbonate TBBA oligomer or brominated polystyrene. Other flame retardant
uses rarely or restricted(DBDE,DBDE and other)
Bromine containing plastic example:printed circuit board(Contains some TBBA instead Bisphenol A ) PBT plastic Connectors on Motherboard, Electronics
Cases(TBBA polycarbonate oligomer), PS plastic from printer cartriges, monitor and TV case(brominated polystyrene)
Electronic waste big problem in China and some Africa and south America countries. Chinese scientists have developed a method of fixing bromine from
PCB waste(after cooper extraction) by calcination them with calcium carbonate. I checked this method
About 7 kg brominated polystyrene(TV case, printer cartriges) marked as PS-FR17 were calcinated with 1.5 kg mixture calcium carbonate and
hydroxide(5\1) at up to 800-900C for destroy all organic compounds(CO begins to stand out at the end of the process)
After pyrolysis black powder from retort was leached with 5 liter hot water and filtred. Received 3 liter solution(loses bad filtration) with density
1.05 what correspond to 170gr calcium bromide. If to solution add mixture sulfuric acid and hydrogen hydroxide solution still slow red and have
bromine odor. Calcium sulfate is precipitate
The solution was evaporated on the open air in the bowl to about 200 ml concentrated calcium bromide solution was prepared.
This method requires high temperatures and many plastic waste but works
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Texium
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Are you saying you did this and are reporting your results, or is there a question hidden in there somewhere? It reads like you just copied and pasted
a piece of some dubious, machine translated Chinese patent...
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Hexabromobenzene
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No it did it. This is my method. Chinese and other works was used as a source of information
[Edited on 1-12-2021 by Hexabromobenzene]
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Texium
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You claim to have obtained 200 mL of concentrated calcium bromide solution, but you don't have any information on how much bromide is actually in
there... You're relying on the assumption that the only salt in your solution is calcium bromide. Without isolating a reasonably pure bromide salt
from this process, the information is not very useful. A small amount of bromide being present would lead to the results you saw when you added
sulfuric acid and presumably hydrogen peroxide (not "hydrogen hydroxide"), so you didn't prove whether you succeeded in extracting a worthwhile amount
of bromide.
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Hexabromobenzene
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I get 3 liter solution with density 1.05. I see in calcium bromide solution density table and it correspond to 170gr calcium bromide. After
evaporation to 200ml concentration increases. Calcium bromide is difficult to get in dry form. What do you know well-soluble calcium salts which are
stable at high temperatures? Chloride?
But I did not have gas bubbles and chlorine smell
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Oxy
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This looks interesting.
Are you able to titrate the product to confirm your assumptions?
I agree with Texium, your assumption might be wrong. In Europe bromides are kind of cheap so if it's not easy to isolate them easily and with
reasonable cost then it might be not worth from economical perspective.
But it's very easy to verify it by using simple, good, old analytical methods. If you don't have analytical glassware then you might simply take some
of it and convert to bromine as much as you can. Knowing the yield you will know how much of bromides you have there.
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draculic acid69
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It would be better to isolate the resulting product in the form of pure elemental bromine to get an idea of how much br- is actually in there. Or
maybe how much conc. Hbr you could get out of it at least. Trying to determine a yeild from this method in the form of CaBr doesn't sound accurate.
I'm also curious as to what are the products of thermal decomposition at lower temperatures can the organobromine compounds be isolated or are they
destroyed? And in your method how sure are you that no bromine was promised?
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unionised
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How did you rule out CaCl2 or acetate?
To be fair, if you got enough calcium into solution to get the density up to 1.05, you must have got some reaction
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karlos³
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This is interesting, as the other "raw chemistry" stuff from yours.
But please do more analysis!
What you got is not pure, do some more purification on it please!
If you can not obtain it dry, its because its totally dirty.
verrückt und wissenschaftlich
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Hexabromobenzene
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Distillation Bromine at home very unpleasant employment. I can heat bromide with permanganate and acid. Brown vapor show presence bromine. But a
little later
Main products decomposition brominated polystyrene is styrene and p-bromostyrene, but they fully burn in the furnace with fuel(Pine boards). TBBA give
phenol and some bromophenols.
For full plastic decomposition need to heat at least 700 degrees about hour(900 degrees are better and faster)
Calcium acetate decompose in these conditions.
P.S
700 degrees is red hot
900 degress is orange hot
[Edited on 6-12-2021 by Hexabromobenzene]
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