The Hive => Newbee Forum => Topic started by: experimentalbois on January 20, 2003, 05:23:00 PM
Title: Temperature Problems
Post by: experimentalbois on January 20, 2003, 05:23:00 PM
A certain somebody was telling me that when distilling sassy, the temp wouldn't go above 80C under vacuum, even with the hotplate on high. (Using a 500mL RBF immersed in peanut oil in an anodized iron flat bottom pot on the hotplate.) He thought it was the used hotplate, but conditions didn't improve even with a brand new hotplate. The hotplate was tested to heat water in the iron pot and the temp of the water reached 100C so...any ideas as to why the setup with the peanut oil isn't doing the trick?
Title: there is no actual max temp
Post by: Wargasm on January 20, 2003, 05:45:00 PM
that the safrole will come over. The temp you get your safrole will be dependant on how strong your vac pump is. A good rotary vane can distill safrole lower than 80C, but a diaphragm pump may not. A common way bees use to determine how strong there vac is is to distill H2O under vac and see where it comes over. There is a table on Rhodium's site that will tell you how strong your vac is. What kind of vac setup are you using? I think you may need to do a little more reading. Look up temp/pressure characteristic curves.
Title: again
Post by: hCiLdOdUeDn on January 20, 2003, 05:50:00 PM
Read this again and again and again and your problems will bee solved!
Title: the kind of vac setup that someone said ...
Post by: experimentalbois on January 20, 2003, 06:31:00 PM
the kind of vac setup that someone said they're using is a water aspirator....i'm gonna tell someone to go to rhodium's site at a secure location
Title: one other little addition to this inquiry:...
Post by: experimentalbois on January 20, 2003, 08:53:00 PM
one other little addition to this inquiry: why, when the water pressure drops on someone's system (due to someone else in the building showering), does the temperature fall drastically? Shouldn't the temp rise due to a decrease in the vacuum?
Title: nothing is touching the thermometer
Post by: goiterjoe on January 20, 2003, 08:59:00 PM
When the vacuum drops in your flask, the distillate stops boiling and your thermometer cools down because nothing is coming over. Your distillate doesn't just instantly rise in temperature because the pressure increased a minute amount.