I can only think that a small sample can be sublimed while a bigger sample size can be recrystallized. Are there more?
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2$\begingroup$ Thermal stability of the material $\endgroup$– Klaus-Dieter WarzechaNov 17, 2016 at 15:22
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$\begingroup$ Sublimation requires specialist equipment $\endgroup$– WaylanderNov 6, 2017 at 16:57
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1$\begingroup$ Most chemicals don't sublime under reasonable conditions... $\endgroup$– matt_blackNov 6, 2017 at 17:46
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$\begingroup$ If the resublimation goes wrong, you can find yourself dismantling the vacuum pump and its exhaust pipe in order to scavenge the rest of your material. $\endgroup$– KarlDec 6, 2017 at 18:44
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3 Answers
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The most notable difference is that sublimation requires a volatile solid, whereas most solid can be recrystallized from a solvent system that is not too exotic. Recrystallizations tend to recover more pure product. In regards to green chemistry, sublimations are preferred as they generate no solvent waste.
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Percent recovery if sublimate is not 100% complete since the fumes may be blown away especially if not executing proper sublimation process.
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I think a possible limitation might be that the compound to be purified should be volatile. And also, you don't really know when the sublimation is completely over. That's why we usually wait approximately 5 min after detecting the first crystals and turn over the heater... I mean, it's not a very accurate procedure.
