Thanks. Sure I haven't pulled all the goods yet, but it was my understanding that with the salt in the mix most of the goodies should be pulled in the first 2-3 pulls. I've seen someone report to have gotten goodies out at the 18th pull. But the steep decline of yield in my case (from 175mg to 80mg) doesn't look promising.
downwardsfromzero wrote:If your naphtha isn't saturated enough it won't precipitate so well, especially if your freezer isn't as cold as it could be.
I don't think my thermometers are very accurate as one measured -20C at setting 3, and another -16C at setting 6, which is supposedly the coldest. But even if we take the more pessimistic value of -16C, that should precipitate the DMT fairly well?
The naptha I pour off after freeze-precipitation is not clear, but cloudy, so perhaps the DMT is not precipitating as well as it should be, or could it be impurities? The cloudiness is white, not yellow or any other coloring.
downwardsfromzero wrote:If you leave that base tea for a month or so, I'll bet that a bunch of DMT floats to the top. But adding a bit more NaOH and pulling again with (the same) naphtha, while making a better attempt at warming things up, should see your overall yield improving without the long wait - unless it's the calcium particulates clinging onto your naphtha.
Will all more NaOH and try and warm things up better.
The mixture settles into three layers (from top to bottom - see attached photo): naptha, a clear(-ish) amber liquid, and a light-brown/grey suspension - presumably the undissolved CaOH. The naptha layer in the photo is thin as most of the naptha was pulled off.
If the calcium is trapping my naptha, I understand if I wait a month the DMT dissolved in the trapped naptha will float to the top naptha layer, but the trapped naptha will still stay at the grey bottom layer, so I'll have to add more naptha to recover it reasonably quickly?
downwardsfromzero wrote:How did the volume of your recovered naphtha pulls compare with the amount originally added?
I didn't measure it, and I'm not basting off all the naptha as the bottle's neck is fairly wide and I don't want any of the basic solution to get into the naptha. For my last pull I'll suck up all the naptha with a bit of basic tea, pour it into a narrow glass and try to recover more naptha.
Edit: I put the 2nd pull (after collecting the crystals) back in the freezer and after a few hours got another 60mg, bringing the yield from the 2nd pull from 80 to 140mg. So the freeze precipitation clearly wasn't complete or the crystals dissolved back into the naptha. Now after the 2 pulls the total yield has gone to 0.425%.
And the reason the thermometer was reading -16C was that it was on top of the pyrex. I put it flat on the bottom of the freezer compartment and the reading dropped to around -28C. Also the pyrex in the 2nd pull was sloping and not flat. I'm going to put it flat from now on, which should improve the efficiency of the freeze precipitation.
Jagube attached the following image(s):

DSC_0388.JPG
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