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Endimion17
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Well, air condensers do serve a purpose. They're used for condensing liquids with a boiling point above ~150 °C because Liebig condenser with flowing
water jacket (10-20 °C water, depending on the season) might burst. Funny enough, Keck clips have the very same limit. 
I'll try to test it like you said and report the results. One of the problems is that I don't have a variable heating equipment. I resort to water and
oil baths, and constantly monitoring the temperature, turning the hotplate on and off. I can never leave a reflux alone, which sometimes means hours
of sitting down. I might try to modify my hotplate but I really don't like messing with electrical equipment.
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watson.fawkes
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Quote: Originally posted by Endimion17  | Well, air condensers do serve a purpose. They're used for condensing liquids with a boiling point above ~150 °C because Liebig condenser with flowing
water jacket (10-20 °C water, depending on the season) might burst.
[...]
I resort to water and oil baths, and constantly monitoring the temperature, turning the hotplate on and off. [...] I might try to modify my hotplate
but I really don't like messing with electrical equipment. |
In addition to air and water, there are other
working fluids you can run through a condenser. The most obvious is automotive radiator fluid, called antifreeze but really "antiboil" to avoid vapor
in the cooling loop, fully of ethylene and propylene glycol with higher boiling points. In general, you need to run such alternatives in a closed
cycle, which means a radiator and a fluid pump. Such small radiators are available at the auto parts store as heater cores, small radiators used to
transfer heat from the engine cooling loop to the passenger compartment. While this isn't a huge investment, it's not cheaper than seeing if air is an
adequate working fluid for you.
Insofar as temperature regulation goes, there's a relatively easy electronics project to control heating mantles. It's a pulse-width modulation (PWM)
for mains power. Heating doesn't require fast PWM; pulses on the order of seconds are just fine. And it will work for any heater. The circuit requires
three semiconductors: a 555 timer chip, a ZC phototriac (zero crossing), and a power triac, you can make a PWM regulator for your mains power; total
cost for these is less than 5 USD. Using a ZC phototriac driver gets rid of the bulk of line noise that you can hear in other triac circuits like lamp
dimmers. The power triac can easily be rated at 15A or 20A, so it would work for any lab scale heater, or even the space heater in a garage. I've
never seen this in a product, because most people need more sophisticated temperature control if they need any at all. And it doesn't regulate
non-heater loads well. But it's just right for a lot of amateur science.
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Texium
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Sorry to bump an old thread, but I felt like I might have a some useful information to add regarding unconventional condenser setups.
Since I don't have a water pump, I just set up a ring stand supporting an upside down milk jug ( with the bottom cut open) with ice water in it that
flows into the condenser, and then a little spigot that pours into a bucket on the other side. You simply pour off the water occasionally, and it will
refill itself. If you use enough ice, you can even reuse the water. I usually keep a plastic pitcher full of water in the freezer so I always have a
nice block of ice to use and it doesn't waste any water. It takes a little while to set up, but it's worked very well for me!
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HgDinis25
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I'm sorry to bring up an old topic but I wanted to show you this:
https://hobbychemistry.wordpress.com/2015/04/03/types-of-con...
It is a general guide, made by me, discussing the most common types of condensers.
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Zombie
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Very nice article HgDinis25. I sort of focus on distillations, and I enjoyed the read.
Actually I am surprised there is not a "sticky" thread explaining most of the hardware available.
Thanks for sharing this.
They tried to have me "put to sleep" so I came back to return the favor.
Zom.
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Bert
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FYI:
Ryobi 120 VAC pump. At Home Depot, less than $18.00. 40 gallons/hour at a moderate but useful pressure- Sold as a universal replacement pump for wet
tile saws, but we might have other applications.
http://m.homedepot.com/p/Ryobi-Universal-Water-Pump-A113UWP/...
Rapopart’s Rules for critical commentary:
1. Attempt to re-express your target’s position so clearly, vividly and fairly that your target says: “Thanks, I wish I’d thought of putting it
that way.”
2. List any points of agreement (especially if they are not matters of general or widespread agreement).
3. Mention anything you have learned from your target.
4. Only then are you permitted to say so much as a word of rebuttal or criticism.
Anatol Rapoport was a Russian-born American mathematical psychologist (1911-2007).
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Amos
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Bert, have you ever used or known someone to use this product? And how is it powered?
[Edited on 4-7-2015 by Amos]
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HgDinis25
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| Quote: Originally posted by Zombie | Very nice article HgDinis25. I sort of focus on distillations, and I enjoyed the read.
Actually I am surprised there is not a "sticky" thread explaining most of the hardware available.
Thanks for sharing this. |
Thanks and I'm glad you enjoyed it! The sticky thing would be very interesting. Covering all range of glassware and apparatus would be quite
interesting.
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Zombie
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| Quote: Originally posted by Amos |
Bert, have you ever used or known someone to use this product? And how is it powered?
[Edited on 4-7-2015 by Amos] |
Amos,
120VAC wall power in the US
They tried to have me "put to sleep" so I came back to return the favor.
Zom.
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aga
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For the Paranoid out there, not all of the walls in the US are permanently charged up with 120VAC.
It's OK to touch US walls, or rest objects against them.
Best use rubber boots, gloves and a shower cap if you're not sure.
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Zombie
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| Quote: Originally posted by aga | For the Paranoid out there, not all of the walls in the US are permanently charged up with 120VAC.
It's OK to touch US walls, or rest objects against them.
Best use rubber boots, gloves and a shower cap if you're not sure. |
 Mine are 120vac. I wired them myself
Rubber boots are a must...
They tried to have me "put to sleep" so I came back to return the favor.
Zom.
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