Ah, I see. What plant material was used? I use q21q21's tek 1 quite a bit. I have never heated the limonene. It pulls most if not everything out after a few pulls of room temp limo.
Everything you mentioned seems normal except for evaporating your limo. D-limonene is known to not evaporate cleanly. It leaves behind residue no matter what purity it is. When smoalked did it taste orange-y?
To recover the rest of your spice (after double boiling the vinegar down to goo) I would recommend using some 99% isopropyl, acetone, or everclear. Swish that around a bit and then pour it into a Pyrex dish to evap.
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