[curiouscat]

What's a good solvent to wash off organic residues from precipitated salt? The salt is mostly NaCl but instead of white it has this brownish dirty color because the solution it was evaporated out of had dissolved organics.

I've tried MEK & Methanol so far but those don't seem to work much.

Not sure of the exact nature of organics but suspect them to be a polymeric residue of styrene.

[discodermolide]

Acetone?
I suppose you can't use chlorinated solvents?

[curiouscat]

Acetone?
I suppose you can't use chlorinated solvents?

Thanks. Will try Acetone.

Chlorinated solvents are ok too. For now.

[curiouscat]

I found it reported that 1 gm Chloroform dissolves approx. 1.25 gm polystyrene. Could solubility really be that high?

[discodermolide]

Try it out.
From the Wiki page:"is easily dissolved by many chlorinated solvents, and many aromatic hydrocarbon solvents. .. it is used to fabricate many objects of commerce. It is attacked by many organic solvents, which dissolve the polymer. "

It may also depend upon the physical state of the polymer, foam, block etc.

[curiouscat]

It may also depend upon the physical state of the polymer, foam, block etc.

Yes, and for me the solid brown residues may not even be polystyrene. That's only an educated guess.

Whatever works!