EugeneOregon
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Let me pass on a tip for those wanting to "clean up" their extract. It is just another way to help purify and is generally based of a technique that I have learned to call counter current seperation. It is an old idea. I have stopped videos so I will describe it. This is a long post that describes how to significantly remove impurities from extract but on a budget. It requires handling of chemicals that catch fire easily so no sparks or flames allowed and a well ventilated room is needed. A simple distillation rig can recover all the solvent for reuse indefinately if desired.
I use a 500ml sep funnel for this but could be any size. This is a way that could be called liquid-liquid chromatography as it achieves the same kind of results but with no solid stationary phase (like silica gel). The advantage is zero loss of product, no use of silica gel, and if desired 100% solvent recovery. I use this prior to distillation and purities achieved by distillation are VERY high when pre-distillation seperations are done first. The problem with chromatography is it is messy and leaves behind gunked up silica gel which adds to cost. Worse though is that because of azeotropes formed with standard chromatography chemicals it is nearly impossible to reuse the chemicals again because they cannot easily be made pure again. Counter current seperation gets around this and even without distillation later can substantially improve the purity of supercritcal fluid extraction extracts.
Here is how the procedure goes. You must use hexane (any grade is fine), methanol (no other alcohol except methanol), and water. The hexane will be the "staionary" phase and the methanol/water gradient will be the "mobile" phase. The whole idea is based upon the fact that methanol and hexane are not miscible in each other. Water and hexane are not miscible in each other. Methanol and water mix are miscible in any ratio with each other. Extract will disolve in methanol and will disolve in hexane but will not disolve in water. Parts of the extract prefer to disolve in methanol over hexane but the methanol must be "tuned" in its disolving power (polarity) in steps to select just the parts of the extract we are after. First we can collect more polar compounds normally considered undesirable and set aside, then ramp up the methanol ratio and capture the cannabinoids at certain ratios from out of the hexane. We will leave behind the dark undesirable gunk in the hexane layer.
1) Disolve your dewaxed extract in 100 ml hexane. The volume is chosen based on my use of a 500ml seperation flask and could be any volume that makes sense.
2) Place the disolved extract in hexane into the seperation funnel.
3) Mix 30% methanol with 70% water in a 100 ml flask. Pour this into the seperation funnel.
4) Cap the seperation funnel and invert a few times to force the liquids to mix but do not shake vigorously. No need to created an emulsion, just wash from side to side a few times.
5) Allow the hexane to seperate on top of the methanol/water mix. Depending on starting extract you will likely see a great deal of white and even solid matter in the methanol/water at first. Decant from the bottom of the sep funnel and save for solvent recovery (or just toss this part). Be careful not to let any of the top hexane layer out of the bottom of the sep funnel. It stays fixed in the funnel as the stationary phase. Repeat the 30% methanol washes until the methanol layer is clear. This part of the extract is not cannabinoid and can be tossed or solvent recovered.
6) Increase the ratio of methanol to water to 60% methanol/40% water. 100 ml. Repeat the wash and save the methanol (bottom layer). Likely the color will change from water white to yellow at somewhere around this ratio and higher. Decant the bottom methanol layer. Save all from this point forward.
7) Now increase the methanol in 10% steps and add to the hexane/extract mix. So add/wash with 70%,80%, and 90% methanol to water n 100 ml steps. Save all. The hexane layer gets pretty dark. It will vary according to starting extract so the trick is to watch the color of the bottom layer.
8) At somewhere around 90% methanol the bottom phase begins to get darker but not tar black like the hexane will normally be by now. I go up to 95% methanol/water and wash this through the hexane phase repeatedly until it substantially runs clear as the bottom phase.
Save off all the methanol/water phases washed through. I combine light colors in the methanol washes in one dish and the darker colors in another. (light colors start at about 60% methanol/water and dark ones above about 90% methanol/water). The hexane layer is dark tar. Methanol can be purified by fractional distillation of the water because methanol and water do not form an azeotrope. Methanol and hexane do form an azeotrope but adding water to the methanol breaks the azeotrope so it too can be seperated this way easily this way by fractional distillation.
It varies according to all kinds of factors but at room temp in my set up by ramping up the methanol in 10% steps and watching for the colors that get extracted from the hexane seems to work best. Over 95% methanol/water seems to pull too much darker material over. Less than 90% pulls much lighter material in my set up. This may be a bit different in your rig but you get the idea.
The huge advantage is that if you totally screw up but save all your solvent then you can just distill off the solvent and recovery all your starting extract. When you screw up a chromatography run it is not so easy to recover everything and start over lolz.
I use a 500ml sep funnel for this but could be any size. This is a way that could be called liquid-liquid chromatography as it achieves the same kind of results but with no solid stationary phase (like silica gel). The advantage is zero loss of product, no use of silica gel, and if desired 100% solvent recovery. I use this prior to distillation and purities achieved by distillation are VERY high when pre-distillation seperations are done first. The problem with chromatography is it is messy and leaves behind gunked up silica gel which adds to cost. Worse though is that because of azeotropes formed with standard chromatography chemicals it is nearly impossible to reuse the chemicals again because they cannot easily be made pure again. Counter current seperation gets around this and even without distillation later can substantially improve the purity of supercritcal fluid extraction extracts.
Here is how the procedure goes. You must use hexane (any grade is fine), methanol (no other alcohol except methanol), and water. The hexane will be the "staionary" phase and the methanol/water gradient will be the "mobile" phase. The whole idea is based upon the fact that methanol and hexane are not miscible in each other. Water and hexane are not miscible in each other. Methanol and water mix are miscible in any ratio with each other. Extract will disolve in methanol and will disolve in hexane but will not disolve in water. Parts of the extract prefer to disolve in methanol over hexane but the methanol must be "tuned" in its disolving power (polarity) in steps to select just the parts of the extract we are after. First we can collect more polar compounds normally considered undesirable and set aside, then ramp up the methanol ratio and capture the cannabinoids at certain ratios from out of the hexane. We will leave behind the dark undesirable gunk in the hexane layer.
1) Disolve your dewaxed extract in 100 ml hexane. The volume is chosen based on my use of a 500ml seperation flask and could be any volume that makes sense.
2) Place the disolved extract in hexane into the seperation funnel.
3) Mix 30% methanol with 70% water in a 100 ml flask. Pour this into the seperation funnel.
4) Cap the seperation funnel and invert a few times to force the liquids to mix but do not shake vigorously. No need to created an emulsion, just wash from side to side a few times.
5) Allow the hexane to seperate on top of the methanol/water mix. Depending on starting extract you will likely see a great deal of white and even solid matter in the methanol/water at first. Decant from the bottom of the sep funnel and save for solvent recovery (or just toss this part). Be careful not to let any of the top hexane layer out of the bottom of the sep funnel. It stays fixed in the funnel as the stationary phase. Repeat the 30% methanol washes until the methanol layer is clear. This part of the extract is not cannabinoid and can be tossed or solvent recovered.
6) Increase the ratio of methanol to water to 60% methanol/40% water. 100 ml. Repeat the wash and save the methanol (bottom layer). Likely the color will change from water white to yellow at somewhere around this ratio and higher. Decant the bottom methanol layer. Save all from this point forward.
7) Now increase the methanol in 10% steps and add to the hexane/extract mix. So add/wash with 70%,80%, and 90% methanol to water n 100 ml steps. Save all. The hexane layer gets pretty dark. It will vary according to starting extract so the trick is to watch the color of the bottom layer.
8) At somewhere around 90% methanol the bottom phase begins to get darker but not tar black like the hexane will normally be by now. I go up to 95% methanol/water and wash this through the hexane phase repeatedly until it substantially runs clear as the bottom phase.
Save off all the methanol/water phases washed through. I combine light colors in the methanol washes in one dish and the darker colors in another. (light colors start at about 60% methanol/water and dark ones above about 90% methanol/water). The hexane layer is dark tar. Methanol can be purified by fractional distillation of the water because methanol and water do not form an azeotrope. Methanol and hexane do form an azeotrope but adding water to the methanol breaks the azeotrope so it too can be seperated this way easily this way by fractional distillation.
It varies according to all kinds of factors but at room temp in my set up by ramping up the methanol in 10% steps and watching for the colors that get extracted from the hexane seems to work best. Over 95% methanol/water seems to pull too much darker material over. Less than 90% pulls much lighter material in my set up. This may be a bit different in your rig but you get the idea.
The huge advantage is that if you totally screw up but save all your solvent then you can just distill off the solvent and recovery all your starting extract. When you screw up a chromatography run it is not so easy to recover everything and start over lolz.
