Author Topic: please comment on the following vacuum pump  (Read 3412 times)

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sponsan

  • Guest
please comment on the following vacuum pump
« on: May 13, 2002, 01:31:00 PM »
Hello bees!

Dreaming of getting this particular rotary oil circultion vacuum pump.  Following are some of it's specs:

Pumping speed (m3/h): 3.0
Total Final pressure (Abs) (mbar): 2

Description:
...suitable for evacuation of small closed systems or for continuous suction within a pressure range from 200 to 2 mbar (ABS).

Would this pump be suitable for high vacuum distillations such as distillations of high boiling point oils and ketones?

Thanks heaps!
;)



Thank you,
Sponsan.

hest

  • Guest
pump
« Reply #1 on: May 13, 2002, 04:38:00 PM »
2mbar is not a high wacum, An oilpum should go down to 0.05mbar.

wyndowlicker

  • Guest
hey now!
« Reply #2 on: May 13, 2002, 10:09:00 PM »
check out the ritchie yellowjacket hvac 1.5 or 3.0 pump.sick skills homey its just a bronco gotta tame her and less than 300.Send a PM for more details now!or UTFSE!  :P

I will choke untill I swallow!Who are you to judge or strike me down!Miss you Kerra!

metwurst

  • Guest
2mbar enough
« Reply #3 on: May 14, 2002, 05:25:00 AM »
edit :2 mbar is about 15 mmHg. As Osmium pointed out, 2mbar is in fact 1.5 mmHg. I dropped the decimal when typing, stupid boy that I am. Thanks Os.   This is a respectable vacuum, though not what would be considered "high vacuum" in any self-respecting lab.
2 mbar is more than adequate to distill the ketone. metwurst has an aspirator station that pulls a mere 25 mbar, and ketone distillation occurs at about 154°C. The ketone does not polymerize, and almost no residue is left in the source flask after a single distillation.

There are better pumps to be had, though they are beyond the financial constraints some people are limited by.

(argh! I'm now guilty of misinformation.)

Osmium

  • Guest
> 2 mbar is about 15 mmHg. No! 2mbar = ...
« Reply #4 on: May 14, 2002, 10:35:00 AM »
> 2 mbar is about 15 mmHg.

No! 2mbar = 1.5mmHg!

2mbar will be more than adequate to distill ketone. But when a pump is rated at 2mbar it will not achieve that kind of vacuum under normal operating conditions. But it should still work.

I'm not fat just horizontally disproportionate.

sponsan

  • Guest
water aspirator station instead of hvac pump
« Reply #5 on: May 15, 2002, 03:07:00 AM »
Hello again bees!

After carefully considering my options and lots of research and being a total novice oz bee, i've decided to drop the idea of buying a vacuum pump or messing around with fridge compressors.

Instead, i have aquired a second-hand Davey water pump, which has a 0.6hp motor and produces about 50PSI pressure at zero suction depth.

I will be building a recirculating aspirator stating simmilar to the one discussed on the web site using this pump.

I am also aquiring a brass water/air aspirator, which i am going to hook up to this pump.  The aspirator is fitted with a non-return valve.

For measuring the vacuum created, i am planning to use an automotive boost/vac gauge.  These gauges are relatively cheap over here, and the one i am looking at has a range of 30" Hg to 20 PSI, should be able to tell me approximately what vacuum my aspirator is generating.

Could someone please tell me if i am on the right track so far?




Thank you,
Sponsan.