Sciencemadness Discussion Board

Putting BaSO4 to use?

Antiswat - 19-9-2021 at 00:56

it seems you cant NaOH BaSO4 nor react it with any acid
barium salts can be very useful for reactions such as
(NH4)2SO4 + Ba(ClO4)2 = NH4ClO4 + BaSO4

and seperating iodate from iodide, as with bromate/bromide
but how does one get to recycle barium sulfate? is high reaction temperatures required, such as pyrotechnic reduction using coke or metal powders even?

Amos - 19-9-2021 at 06:09

Prolonged boiling/heating (I'm talking literal days) of barium sulfate in a solution of sodium carbonate slowly converts it back into barium carbonate. Even if the product material still contains remaining sulfate, due to barium sulfate's virtual insolubility it can still be partially reacted with acids to make new water soluble barium salts, and the remaining insoluble barium sulfate can be recycled once again.

Barium sulfate is also relatively easy to reduce with carbon at temperatures that can be accomplished by a furnace, fireplace, etc. The resulting barium sulfide is water-soluble and easily leached from the remaining sulfate and carbon, which again can be recycled. This can be used as a source of sulfide ion or simply converted back to carbonate using Na2CO3. The sodium sulfide coproduct is also useful, and while difficult to isolate from solution should be purer than much of the commercial material if handled properly.

S.C. Wack - 19-9-2021 at 10:26

"It has been found that barium sulfate can be decomposed to the extent of over 99 per cent in a single operation, by boiling for 1 hour (or 2 hours in the case of barite) with a strong solution containing at least fifteen times the theoretical amount of sodium carbonate."

https://doi.org/10.1021/ac50065a014

Antiswat - 22-10-2021 at 04:25

brilliant- i suppose lead sulfate may be dealt with in the same manner, which is really cool as used car batteries arent too hard to come by

when i read carbonate, i dont see why hydroxide wouldnt work same way? and people will say, thats super corrosive- well stainless steel 316 only corrodes about 1mm a year handling boiling, liquid, NaOH

could we maybe assume boiling hydroxide would work better? very interesting turning useless stuff into useful stuff, calcium sulfate is also a major waste product around the world, its ridiculous the amounts of chemicals we pay money to bury in the ground.

S.C. Wack - 22-10-2021 at 16:59

Dead car batteries have liitle sulfate in them, as electrode failure is typically mechanical not chemical...I wouldn't count on recovering baryta, but it would be an interesting experiment.

unionised - 23-10-2021 at 04:20

Quote: Originally posted by Antiswat  


when i read carbonate, i dont see why hydroxide wouldnt work same way?

could we maybe assume boiling hydroxide would work better? .

No
Barium hydroxide is soluble in water.
Barium carbonate isn't.

vmelkon - 24-10-2021 at 18:24

Quote: Originally posted by S.C. Wack  
Dead car batteries have liitle sulfate in them, as electrode failure is typically mechanical not chemical...I wouldn't count on recovering baryta, but it would be an interesting experiment.


From the few car batteries I have dumpster dived, they often give 4 to 7 V.
So, the serial connection between the cells is ok. There is of course some mechanical damage (The grid is fragile or breaky).
If you attempt to charge them, the voltage goes up. Once you stop charging them, the voltage drops quickly on its own. In a few days, it will return to 4 to 7 V.

The good news is that the cathode has some PbO2, which is a good oxidizer.
You can also reduce it with charcoal easily and have some lead.

macckone - 25-10-2021 at 08:04

Metals like stainless steel are pretty impervious to alkali hydroxides and carbonates.
Aluminum on the other hand ...
Stainless big weakness is halides.

Antiswat - 18-12-2021 at 04:21

i honestly dont see why there isnt lab ware made out of stainless steel alloy- hastelloy C, like crucibles
its 20% molydbenum and can handle highly concentrated sulfuric acid at decent temperatures

aab18011 - 18-12-2021 at 06:07

I have an old vial of Barium sulfate from a highscool lab where we tested solubilities by making them. I kept my barium sulfate and have about 10g. If i have time Ill try and test the boiling with Sodium carbonate.

Antiswat - 12-2-2022 at 07:09

okay so- i got around to messing with barium salts a bit, seeing the light of it being used for making some very special chemical compounds
i tried NaOH + BaSO4, first melting the NaOH with BaSO4, then watering it down and boiling for hours
and of course, this would yield Na2SO4 and Ba(OH)2- but the BaSO4 would be crashing out faster than the Ba(OH)2 would be formed- of course.
so i went ahead and tried with Na2CO3 and BaSO4
boiled it for some hours
added in water, poured off- continued to wash it a few times like this
added in HCl- a lot of CO2 was formed, more so than what should be left of Na2CO3 in the solution, the insoluble matter was not decreased by much at this point however
decanted the liquid off and added some H2SO4- the BaCl2 now turned into BaSO4 and precipitated out- proving that it is indeed possible

very neat- perhaps calcium sulfate could response in similar way. and other insoluble sulfates? if the hydroxide of the metal is insoluble NaOH should also work, more effectively even, maybe a lot more efficiently with molten NaOH

neat uses of barium to be posted in not too long time.

S.C. Wack - 14-2-2022 at 20:59

BTW processing Pb in this way will give a basic carbonate. Unless the (bi)carbonate soln. is not heated with the sulfate, which gives the normal carbonate.

With pottery grade Ba, when adding acid to the carbonate, small amounts of sulfate and contaminants and the insolubility of Ba salts in excess acid may make it seem like there's lots of unconverted sulfate, when there isn't. Any large batch will benefit from stirring and esp. above with Pb.

Antiswat - 18-2-2022 at 06:37

yes sulfides and sulfates in BaCO3, so quite likely its generally produced by reacting ... crude, sulfide contaminated barium sulfate with Na2CO3
i had what seemed like 10g of BaSO4 from dissolving 250g BaCO3 in acid

BaSO4 + Na2CO3 = BaCO3 + Na2SO4

so, it would also produce some sulfate, which is also interesting, especially if your source is calcium sulfate, now you could quite efficiently also produce sulfuric acid from it with membrane electrolysis