Sciencemadness Discussion Board

Quality 3A molecular sieves on a budget?

monolithic - 21-2-2022 at 14:19

Does anyone know of any "good" 3A molecular sieves that are cheaper than Sigma, Alfa, etc.? I've bought unbranded Chinese sieves off Amazon and eBay before. They did work but the pore size was inconsistent as they adsorbed a lot of the solvent that I wanted to dry. Hoping for something a little cheaper than the $150/kg that the big name suppliers charge.

Rainwater - 21-2-2022 at 16:03

You can use different anhydrous compounds to dry solvents. You just need to pick one that's compatible with your solvent.
Like for ethanol, I've read that you can use copper sulfate. I have some CuSO4 drying in the oven now for this purpose.

Tsjerk - 22-2-2022 at 02:07

CuSO4 will dry ethanol, but you should use enough. What I noticed was that anhydrous ethanol can turn blue CuSO4 white. It only works with really dry ethanol, and only when you use a small crystal on e.g. three milliliter. It is a nice test to check whether your ethanol is dry though.

artemov - 22-2-2022 at 02:31

I am looking for a good source of 3A MS too ...

This one seems decent ... but they dun ship out of US I think ...

https://www.ebay.com/itm/192455445739

monolithic - 22-2-2022 at 05:52

I do have some drying agents but I prefer using sieves for certain things.

artemov I wonder who makes those? The last batch of sieves that I bought were from an American company (Sorbent Media Inc.) The quality wasn't that great and I suspect they were rebranded Chinese sieves.

artemov - 22-2-2022 at 06:11

Quote: Originally posted by monolithic  
I do have some drying agents but I prefer using sieves for certain things.

artemov I wonder who makes those? The last batch of sieves that I bought were from an American company (Sorbent Media Inc.) The quality wasn't that great and I suspect they were rebranded Chinese sieves.


Not sure though. You can try messaging them through ebay
https://www.ebay.com/str/moistureboss