I have been having mixed results with freezing for re-xtal and slow evap for re-xtal...can anyone help my methods here?

Using Norm's Tek, I get decent white powder and after seeing the big honking crystal post am now obsessed with getting those fat/phat geometric formations (xtals).

After powder, here are the two methods I have been using.
1) Heat bestine, heat shot glass, put powder in empty shot glass then put in small amount of bestine to disolve. I have been using less than a gram and have been using around 20ml of bestine. Then let it slow evap for at least 24 hours (short time since not using much). I did get good results this way once, but not every time. Usually I get the sticky yellow goo.

2) The second method is exactly like the first, except I put it in the freezer for 24 hours, then let it evap for another 24 hours.

Like I said, I am using under a gram but around 15-20ml of bestine too. What can I do for more consistent results?

Check FAQ for recrystallization instructions

and then the other FAQ question about how to retrieve the crystals after freezing.

hope it helps

Endless, I was looking for these two links but until you posted didn't find. THANKS!
Give me a week and I am sure I will have more ?'s for you.
Thanks again!
5

Hello-hello.

Actually I have some nice xtals right now. Here is my technique:

-I'm using Noman's on MHRB, and freeze precipitation.

-After the DMT has frozen out of the naphtha ( "I use stain remover benzine" ), and slowly pour it to leave the DMT behind in the container.

-I put a few ml of fresh naphtha in the container and heat it under hot tap water. Currently I'm using a 500ml Erlenmeyer flask, the amount I usually freeze precip. is 200-250ml The amount of clean naphtha I use is around 10-15ml

-The clean, hot naphtha dissolves the crystals. I pour it into a petri dish for evaporation. I don't like dust falling into the mixture during evaporation, so I cover the dish with a paper napkin. This slows down evaporation, it often takes 2-3 days for the mixture to crystallize completely.

-And there we go. Pictures shows the half-dried crystals and the evaporation setup.