Last time I looked you didn't need heat to evaporate water, just time. There is an excellent method for growinf BZP crystals around here somewhere, I think the title is snorting BZP, in that thread there is all the info on drying the crystals to avoid all the bad effects of heat. HEAT is an enemy of BZP avoid it, so is light, so is oxygen, so heat and light are not good. Making an hcl salt is so thoughrly discussed in TFSE that I won't go into it here. There is also an excellent method to do make BZP DiHcl salt on erowid if you spend 5 mintues to look.
All the info you asked for is in TFSE and on Erowid, the link is at the bottom of the page right now.
Cy
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