Hi yall, im having 2 problems and i gtreatly could use the help
1.) not getting much separation between fractions and I believe that’s in part to not having enough theoretical plates. Just yesterday I inserted a few rings but havent ran anything thru it yet. so i do believe i may have this figured out but my biggest complication is listed below…
however a big issue im running into is ill start with about 700-1000ml in the HM and by the time i’m done because the HM is now at 200c-205c and nothing else is distilling, well thats my issue. i’m barely getting any yield. from a 700-1k mL start, i probably end up distilling a total of 200- 300 ml, with roughly 60-80% of my original starting material still remaining in the HM flask. what am i doing wrong?
quick overview of what im doing:
2L short path setup…
heating mantle set to 80c, stirrer in HM on, cold trap cold, pumped warmed up, pump below 130 micron on whole system (when gauge hooked to pump directly and only pump, yes i get below 15micron and i do this test every time before i connect to short path to make sure pump is in good shape for run), beginning vapor temp reading 14-17c,. ill start to ramp the temp up on the HM from 80c by about 10c until i get to 120c and i let the HM catch up, from then i turn HM up 5degrees and let it boil and distill, i normally increase my HM 5c whenever the Vapor temp drops 0.5c. (my first two runs i increased the HM by 2c all the way from 120c to 200c. increasing 2c every time my HM would catch up by the 2c, id increase HM by another 2c. i was informed by someone else i was doing that wrong and they told me to do the increase by 5c on HM everytime my vapor temp dropped 0.5c. i made a pass one time like this as well but i did so with a heating pad on distillation head because i thought the room temperature was condensing my vapors in the head before they could reach the temp probe. however i do believe i shouldnt have put the heating pad on my distillation head, regardless my biggest problem of barely any yield and ample material left over in HM still presented itself after the run.,) meanwhile vacuum level is still under 130 micron, 40-80 micron on a good day. so i continue this process until i get to about 190-200c on the HM. thru this whole thing my Vapor temp never gets above 100c and its like I’m getting bits of terps, heads, and tails, but no mains, all mixed in hence bad separation, correct? and definitely not much of a yield or purity. all distillate recovered so far has seem to have had another oil or liquid in the distillate as well and thats where my first problem comes in, the separation but as stated above i do believe i may have fixed that but i havent tested it yet…
my real issue is the lack of distillate im yielding by the end of it. yes i want pure product but i know i cant be doing this right with hat much starting material left over in the hm.
well thats my issue. i’m barely getting any yield. from a 700-1k mL start, i probably end up distilling a total of 200- 300 ml, with roughly 60-80% of my original starting material still remaining in the HM flask. what am i doing wrong?
thank you for all and any help,
Take care every1