Welcome to the Nexus man. I like your handle..
Not to shoot you down or anything, but in order to use pickling lime, you've got to stick to a dry tek, like q21q21's or amor fati's.
If you boil your MHRB in vinegar and water, you'll have to use lye instead.
If you'd still want to consider using the lime with the acid boil, you'd have to reduce it down quite a bit so that when you add the the lime, it's more of a paste than a soup.
I don't have a lot of experience with dry teks, so hopefully someone else can chime in here.
And answers for your questions-
1) I like to use a good bit of water with a splash of vinegar, it doesn't take much, so like 50-75ml for each liter of water.
2) For 50g of root bark, I'd probably use 2 liters of water, 150ml of vinegar and simmer that until it reaches about 400ml (or less) of liquid. Instead of adding it to a jar, I'd put it in a bowl and slowly add the lime until it reaches a pasty consistancy as explained in q21's tek.
3) If you're planning on evaporating the xylene, I'd say use 100-150ml of xylene per pull. You could use more, but I wouldn't use any less than that.
4) You could use less per pull but I'd evap the later pulls separately to see exactly how much you're still getting.
5) Unfortunately you cannot freeze precip xylene. That would rock though. When evapping xylene, I put it in front of a window with a fan blowing the fumes outside. You can put some panty hose over the evap dish to keep any dust or hair from getting in.
6) Concerning getting rid of the excess xylene, instead of using acetone, I recommend using IPA, 99% if you can find it. Just evap it in the same baking dish you used to evap the xylene. I would recommend not using heat just incase it gets too hot and vaporizes your spice. Better safe than sorry.
I'm really not sure if this method you outlined would work or not. If you reduce the mimosa tea down enough, it seems like the lime might work.
Since it's just 50g of bark, I guess it's worth a shot. Let us know how it goes and good luck!

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