Can you provide any more info on your procedure?
This is very helpful. So in the sulphur SOP would you suggest using a copper wand/mesh before washing with the 5% bleach or H2O2 step?
How do you regenerate your copper after?
EDIT: Nevermind found the answer, copper flakes and mild acid.
Very interesting clay info, thanks. 1 wt% still sounds like a lot, especially for a food product (probably for crude oil too). How do they get rid of sulphur down to ppm amounts?
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I would rather suggest another chemical tretment first (H2O2 in basic conditions, or sodium sulfite and air ubbling, or other easy method).
And use copper in later steps, to deal with the remaining last bits elemental sulfur, if this is possible.
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Thanks for the feedback. Do you have any sense of how the sulphur procedure stacks up against the iodine procedure?
Sulfur is much easier to source than iodine.
I never experimented the iodine method though.
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CRC = color remediation chromatography but don’t get hung up on that last word too much, it’s subject to a lot of debate here (i.e. it’s not really chromatography in any strict sense)
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I always thought it was color remediation column. Which helps remove the incorrect term of chromatography as well and the media is usually in a column of some sort.
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Lol I shouldn’t have even commented. CRC=tube of magic dirt
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Saying “chromatography” is not using incorrect terminology. CRC is performing chromatography, though not in the traditional sense, as @SidViscous suggests above. CRC still works on adsorption, utilizes polarity, and does provide “fractions”. How is this not chromatography?
Hey @SidViscous, didn’t we just have this conversation in another thread?! 
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But most people are using it as an absorbent column and are not collecting fractions. They are pushing their entire solution through it and collecting everything that isnt retained in the column.
Unless they are removing most the solvent then loading a “sample” into their CRC and then collecting fractions i would not consider it chromatography.
Yes some people are doing it this way but the majority are not.
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Looks like they can test for iodine as well. I don’t think it’d be too much to ask, for people using the iodine method to get that tested as well. I wouldn’t want any iodine or sulfur left over in my products.
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I’m not arguing the terminology of chromatography. I agree they are using a chromatography column, but they could be using it in a better way.
Compare it to driving a 40’ semi truck to work every day. its gets you to work but it could also be used in a much more effective manner. That doesnt mean you are using the truck wrong but it could be utilized better.
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But you are arguing the definition of chromatography. You said:
I am saying that CRC is chromatography and that the definition of CRC that @SidViscous and I hold falls in line with the textbook definition. You also now seem to agree with me, but it’s unclear as to what extent.
CRC does not need to be performed in a column, and many use hochstrom filters and buchner funnels to perform the same trick. I believe my definition does a better job of encompassing what is happening (chromatography) and the variance in vessels used to perform the trick (not always done with a column or cartridge).
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Further devil’s advocacy: the term “column” does separate it from the methods involving hot scrubbing/mixing the media in a boiling flask and then straining. Even a buchner/hochstrom really are columns depending on the flexibility of your terms.
I also think that this is a pointless semantic argument as long as everyone is on the same page. I still like “magic dirt tube” best
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The alternative method mixing material and scrubber together followed by filtration would be termed “batch processing”.
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Even if said batch processing filters through a media bed? Most I know who do batch processing as you have described filter the media out of the solution using more (or a different flavor of) media.
If filtering two dimensionally (quantitative filter paper or something of the like), I would agree that a separate definition would be appropriate. If filtering (scrubbing) media out of a solution is performed with depth filtration (3D), then it still falls under the definition of chromatography, as the filter bed will cause the solution to elute components at different speeds/times (regardless of whether all “fractions” are collected together and mixed).
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Yes. It depends where the remediation process occurs.
I was dealing with simple filtration as a physical separation process.
But if some chemical separation occurs there, then it turns to chromatography.
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Any idea how effective the thiosulfate washes are? I’d expect to tell if the majority iodine and its products are gone just by looking at the color.