Roto Vap Pressure

Depends on what youre evaporating! If youre that hot u will probably rip solvent through your vac and not know it other than that buzzed feeling from huffing fumes! Youre using back pressure (hot water bath) along with negative pressure (vac) to move solvent up just high enough to leave your oil and be recondensed by your chiller (without flying past your chiller)

My chiller is set to -10 c and operates at 3 c without dry ice and -3 with dry ice (see posts above about inline dry ice coil)

My water bath starts out at 23 c when im dealing with ethanol and once my flask is very thick with oil i work my way up to as high as 60 c.

My vac gets all the way down to -750 mm hg or -29 in hg or -1 kpa.

My rotation is a little sketch when flask is heavy so I keep an eye on everything frequently.

Make sure u have a valve tee’d into your vac hose so u can go in and out of vac manually if needed.

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