About 2 weeks ago I did an A/B extraction on 400g of MHRB using citric acid as my acid and NaOH as my base. I used Xylene as my solvent in an effort to pull jungle spice. However when it all evaporated I was left with nothing but a solid inch layer of plastic layering the bottom of my Pyrex dish.

I shall briefly describe the tek I used:
MHRB, water and citric acid are mixed.
3 acid boils in a gallon stainless steel stockpot.
Liquids combined and MHRB filtered out and put into a plastic 5 litre bottle.
NaOH was added to at least pH 11.
While still hot from the NaOH reaction, the Xylene was added.
Xylene was separated from the NaOH/MHRB liquid and poured into a pyrex dish.
The dish was left to evaporate leaving the plastic on the bottom of the pyrex dish. :evil:

What have I done wrong?

Have I brought the wrong solvent or do I have a different solvent to Xylene?
Or...
Would it be possible that the Xylene somehow dissolved the plastic when extracting?

You say you used a plastic 5 liter bottle, yet you don't state that it was hdpe, glass, or any special container. This leads me to conclude you used a plastic that was unsuitable for exposure to petrochemicals and thus, some of the plastic leached into the xylene. When you evaporated your xylene it left you with a jungle spice infused layer of plastic. If this is what happened, imo, your batch is lost (or at the very least I am at a loss as to how you would go about safely trying to recover a product that would be plastic-free) unless someone with more chemistry expertise has a solution.

If I'm wrong and you used a verified container, lemme know as that shoots my theory to shreds.

No the 5 litre bottle I Used was a standard supermarket water bottle. I think the scientific name is; Polyethylene terephthalate.

And yes I have all ready removed and thrown out the Plastic/Jungle extract. I do not want to run the risk of inhaling plastic fumes. It may be able to be salvaged, but it would require more solvents and expense. I would prefer to start the next extraction project instead.

lesson of the day: PET + xylene = bad

In fact, forget PET for using with any non-polar, or for extractions in general I would say! Glass all the way, or HDPE.. but even HDPE shouldnt be used for some solvents, I think aromatics in general shouldnt be used with HDPE, only glass... When in doubt, google chemical compatibility (or resistance) charts before using a material of unknown resistance to a given chemical. Safety first!

Ok, thanks. I guess that I have learnt a very expensive lesson from all this. haha

Such a shame that that little extra research could have benefited me so much.

^ Even if you are going for jungle spice, I highly suggest pulling with Naphtha first. Xylene is such a nasty chemical, and purifying from a xylene extract takes patience and time. You may also consider switching to Toluene, while not safter, it sure does smell 100000x better.

Do 3 nice pulls with naphtha, freeze it, get your spice, and THEN add your xylene, you'll pull at ton more spice and all those other strange alkaloids as well. You can then evap that and you will have most likely increased your yield.

The same kind of thing can happen with d-limonene, acetone, MEK, etc. When using plastic, always check to see if its compatible with the solvents used. The best plastics are HPDE, PP, and PTFE (the absolute best), but even then, check before using a solvent with them.

Is it possible that the xylene you were using just had some nasty binding substance in it?

When I first started extracting, I used hot xylene in a PET bottle and never had an inch of plastic...? I mean an inch? If you melted a whole bottle of that size down I doubt you'd have an inch thickness, unless you were using a very large bottle and noticed an inch worth of plastic missing.

Is it possible to redisolve your plastic in the same solvent and salt out again?

I threw the plastic out, sorry. I do think the Xylene (which was brought off eBay ) may have had something in it that contributed to the plastic as well. However the Xylene had dissolved a fair amount of the plastic bottle, so I have no idea.

One thing I have decided to invest in is a set of glassware for future extractions. This is because in some plastics, other toxic compounds may extracted by the solvent, that are not so easy to identify as a layer of platic. This has been a wake up call to me.

Maybe try, after pulling the xylene, add vinegar to the xylene. You'll get dmt-acetate in the vinegar. Then let the vinegar evaporate instead of xylene. It seems much safer.