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Suppose I have a solid compound from which I want to extract a target chemical I know is soluble in acetone. So I crush and mix the compound in acetone, dissolving the target and suspending the detritus.

  1. What are methods for filtering the detritus from the solution? I have frequently seen coffee filters used for this purpose. Are commercial coffee filters considered "lab-grade?" Or, suppose that the target chemical has some affinity for cellulose, what alternatives exist for suspension filtration?

  2. Now, having the target chemical in solution I assume it is easiest to extract it by evaporating the acetone. Is there a process for this that doesn't leave any of the target stuck to the glass or whatever was containing the solution?

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What are methods for filtering the detritus from the solution? I have frequently seen coffee filters used for this purpose. Are commercial coffee filters considered "lab-grade?" Or, suppose that the target chemical has some affinity for cellulose, what alternatives exist for suspension filtration?

The method that comes to mind for this task is a Soxhlet extraction. Commercial coffee filters are not "lab-grade." Soxhlet extraction thimbles are available in cellulose.

Now, having the target chemical in solution I assume it is easiest to extract it by evaporating the acetone. Is there a process for this that doesn't leave any of the target stuck to the glass or whatever was containing the solution?

Yes - rotary evaporation, in conjunction with Soxhlet extraction.

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  • $\begingroup$ I don't follow the second answer: How does rotary evaporation avoid adhesion problems? $\endgroup$ – feetwet Jun 19 '15 at 1:36
  • $\begingroup$ The rotation of the evaporation flask ensures that a minimal amount of solute remains on the wall of the flask. As you probably suspect, it's not perfect: you will still have to wash down the sides of the flask with the solvent of your choice, pour it out, and dry it on a watch glass. In my opinion, it's the best way to quickly concentrate an extraction without inducing thermal decomposition/reaction. $\endgroup$ – Todd Minehardt Jun 19 '15 at 1:48
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    $\begingroup$ A typical undergraduate experiment is the extraction of the triglyceride of myristic acid from nutmeg using Soxhlet apparatus. $\endgroup$ – Beerhunter Jun 19 '15 at 8:08

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