5 replies to this topic

[willowchar]

Wondering if there is a process to purify barium sulfate. I have access to 1000 gm that has a slight amber hue to it. It dose not perform well in strobe propellant. I switched it with synthesized barium sulfate (white) in the same comp and everything worked fine.

The product was purchased from a pigment supplier. I suspect it is of the mineral type accompanied with some sort of impurities?

I believe there must be an easy way to purify it rather going through the laborious route to synthesize it.

 

Thanks

[justvisiting]

I have synthesized my own barium sulfate and used it in strobe rockets. I'm no chemist, but I think making your own barium sulfate would be easier than trying to purify your product, because your product will have to be dissolved in acid first, in order to purify it. I used crappy barium chlorate I bought, and reacted it with epsom salts (magnesium sulfate heptahydrate). You could use barium nitrate and magnesium sulfate to make barium sulfate reasonably cheaply. I settled, decanted, repeated, until the magnesium salt was gone, and dried the resulting product. It was really difficult to get it to give up the water it held onto, which still baffles me. Next time I make it I am going to dry the barium sulfate slurry on a plaster of paris slab.

[Mumbles]

One thought is to wash your barium sulfate with a dilute acid.  Something like HCl or Acetic acid maybe.  Effectively you want to see if you can wash away the impurities.  This is kind of opposed to the normal method of purifying the product out of the impure mixture.  You "purify" the less desirable things out of the impure mixture.  Ceramic grade barium sulfate often has some extra things in it, as you mentioned, from the mineral source.  This most often is barium carbonate and barium sulfide.  You'll want to do this outdoors.  Barium sulfide will make hydrogen sulfide which is both toxic and smells really bad.  Those things will hopefully be turned into a soluble barium compound with the use of HCl or acetic acid, and will wash away.  You'd want to follow up with some distilled water washes to remove all of it and anything else that might wash away.  This mixture is going to contain soluble barium salts (hopefully) and will be hazardous.  I'd suggest adding magnesium sulfate or something to it to precipitate it back out as barium sulfate, which can be reisolated. That's just an added bonus in this method.

 

I'm not saying this is going to work, but it's at least a starting point.

[WSM]

Wondering if there is a process to purify barium sulfate. I have access to 1000 gm that has a slight amber hue to it. It dose not perform well in strobe propellant. I switched it with synthesized barium sulfate (white) in the same comp and everything worked fine.

The product was purchased from a pigment supplier. I suspect it is of the mineral type accompanied with some sort of impurities?

I believe there must be an easy way to purify it rather going through the laborious route to synthesize it.

Thanks

 

 

The product you bought sounds familiar. I believe what you have is called barytes, and is a powdered natural ore of barium. It's principally barium sulfate but typically contaminated with other minerals.

 

"The most common gangue (contaminating) minerals are quartz or other forms of silica (chert, drusy quartz, and jasperoid), sulfide minerals (galena, marcasite, pyrite, and sphalerite), clay minerals, carbonates (calcite and siderite), and iron oxides. Organic matter can also be present at concentrations up to several weight percent."

 

I believe Mumbles has offered good "starting point" suggestions if you intend to try purifying the material you purchased. Otherwise, you may want to find other uses for it and purchase purer forms of barium sulfate to use in pyrotechnics.

 

Good luck.

 

WSM

[pyrojig]

With the price you could fetch with selling the barrium chlorate, you could buy 4x as much sulfate.

[justvisiting]

I used barium chlorate because it was crappy. It did not produce a good green, even after re-crystallizing. If I didn't have a useless but soluble barium salt to start with, I'd have used barium nitrate and epsom salt. Both are cheap enough, and readily available.