SWIM is using low-low bp fractions of pet. ether. The dude had an idea of popping a graham condenser on top of a FB boiling flask and heating the solvent to boiling. The solvent's top fraction is 60 degrees, so it should never get hot enough to boil any spice.
Is this crazy?
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Well its not necessary. But refluxing would prevent the solvent from evaporating.
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And even temperatures below the boiling point of spice will not stop some of it from evaporating away. Just as water does not need to boil in order to evaporate away. That is in case this dude is not refluxing but trying to distil the low bp pet.ether in pursuit of leaving the spice behind. Need to calculate between salts and freebases? Click here! Need to calculate freebase or salt percentage at a given pH? Click here!
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Boiling water would be bad. In this case the reflux would happen at 70 degrees centigrade. That is true about evaporation, but in a reflux set up the evaporation should be contained.
While reflux is not necessary, it would seem that in the prolonged heating (10 min or so) may help. Or may not.
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Now I have no idea what you're talking aboot! Need to calculate between salts and freebases? Click here! Need to calculate freebase or salt percentage at a given pH? Click here!
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Hah! Apologies! Typically refluxing's purpose is to allow reactions to occur under heat for a long time. In this case SWIM would reflux at a temperature less than the boiling point of water and slightly above the boiling point of the solvent. The rational is that hot solvent dissolves stuff better and that the convective currents in the water would perform the stirring. Boiling solvent would be the indicator to remove heat.
In essence it's simple heating, not refluxing, but with the advantage would be that the condenser would catch the vapor.
It makes sense that actually refluxing, ie boiling the shit out of it, would be pointless and a bad thing.
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Yes and your right a bit of heat does help during non polar extraction but a sustained reflux is not necessary. Only a bit of heat is needed. Even if working with a volatile solvent like hexane the extraction can be done at milder temperatures. But if you want to use a condensor to keep the solvent from evaporating during a gentle heating then go for it can't hurt. Will keep the area less fumed out too.
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