zenosx
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Location: East TN / Near Oak Ridge
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Vaccum from Aspirator
This was such a newb question I stuck it here in beginnings.
So during my benzyl chloride vacuum distillation I observed the primary fraction coming over @ ~ 80°-82°C. For the second fraction I observed ~
96°-99°C and third fraction at ~112°-120°C. (3rd was possibly just me increasing the heat to speed up the distillation as it was not coming over
very quickly anymore.)
From the starting reaction there were only 3 possible fractions (not counting side reactions)
Benzyl Alcohol - BP:205°C
Benzyl Chloride - BP: 179°C
Water - BP: 100°C
HCL: (would have left quickly)
That is probably too much data but my question is, I am trying to determine my new aspirators vacuum supply. Very loosely going from my nomograph I
predicted ~ 20 Torr on the first fraction of 80°C.
Does this sound reasonable or am I wayyy off..for an aspirator. There is so much crap out there and so many wildly fluctuating figures I figured I
would ask for my setup.
Thanks for reading this long post...
A question that sometimes drives me hazy: am I or are the others crazy?
Albert Einstein
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Metacelsus
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My aspirator gets down to 50 torr pretty reliably, but no lower. The theoretical minimum for an aspirator is about 18 torr, assuming 20 C water.
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zenosx
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Well I was using my nomograph taped to the wall near my lab and an inoculation loop as the key.. so there is a large margin of error.
I am using a new nickel aspirator that I just installed, and 50 torr max sounds reasonable. Thanks for the input.
IMHO that is still a respectable vacuum to be had from an aspirator....
A question that sometimes drives me hazy: am I or are the others crazy?
Albert Einstein
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zenosx
Hazard to Others
Posts: 188
Registered: 7-7-2012
Location: East TN / Near Oak Ridge
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Mood: Awaiting Results....
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I think I'll do a control test of water BP and see what I get. I had just installed this source and needed to distill this high BP solvent/reagent. I
have so little lab time that it literally took 4 weeks to just get time to distill the reaction product...
A question that sometimes drives me hazy: am I or are the others crazy?
Albert Einstein
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