Sulaiman
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cheap eBay distillation kit surprise
I ordered one of the cheap 24/40 500ml distilation kits fom China via eBay
http://www.ebay.co.uk/itm/351749512267?_trksid=p2060353.m274...
it arrived yesterday
... seems good quality, no bubbles, smooth glass with fairly consistent thickness and good fitting joints ...
very nice.
only one detail wrong ... 24/28 size ... yes, 28, not 29, and certainly not 40 !
I do not really care if the joints are 24/40 or 24/29 or even 24/28, all will work, just thought I'd share the 24/28 photo as I've never come across
24/28 before.
[Edited on 30-6-2016 by Sulaiman]
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The Volatile Chemist
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Now that is strange. And they're Bomex too...
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aga
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The cheap chinese glass has all worked fine for me so far.
Last week the first ever vacuum distillation was attempted, and the entire chinese-made disty rig withstood the heat & vacuum without even a
single *tink*.
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Sulaiman
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A riddle
Why is it that in my new kit, and many that I have seen advertised,
a 105 degree still head adapter + a 75 degree receiver adapter is much less than 180 degrees ?
I think I may prefer distillate dribbling down the flask rather than dripping into it ... tbd
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aga
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Tip it all sideways a bit ?
Cheap stuff is what it is, improvise or spend more.
Edit:
Please reduce that image size to what it was Earlier (i.e. smaller) as super-sized images is becoming a Hallmark.
[Edited on 29-6-2016 by aga]
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Sulaiman
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no, I meant that the kit I have assembles with the receiving flask at an angle to the vertical,
http://i.ebayimg.com/00/s/NDI1WDU2MQ==/z/S6sAAOSwfcVUBcvj/$_...
so the distillate will dribble down the side of the flask rather than drip into the middle,
I think it may be better = more gentle.
The glassware appears to be very good quality/value, better than I expected.
EDIT: The photo is from a different seller, just to show the angle.
I do not know why the photo' is so large, I inserted it just like all previous images - how do I reduce the size ?
[Edited on 30-6-2016 by Sulaiman]
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aga
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Fail
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Cabalaba
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Be careful with the brandless Chinese stuff. Got a reaction flask with quite a few air pockets, some nearly 2mm wide (the one in the photo wasn't the
biggest either, just the easiest to photo). I wouldn't heat that to 400℃, particularly under vacuum. It may not have resulted in fractures during a
reflux, but do you want to find out how much air can expand while you have hot acid refluxing?
Thankfully eBay's generous buyer protection covered it and don't have to ship it back.
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NEMO-Chemistry
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Quote: Originally posted by aga  | The cheap chinese glass has all worked fine for me so far.
Last week the first ever vacuum distillation was attempted, and the entire chinese-made disty rig withstood the heat & vacuum without even a
single *tink*. |
Can i ask what pressure you took it down too? I have been dithering about using my cheapo Chinese glass for vac distillation, reassuring to hear it
holds up ok.
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aga
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The gaugue read around 100mBar, which is about 75 torr.
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Melgar
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Yeah, just got one myself a few weeks ago. $25 for a 500 mL to 250 mL setup, with keck clamps, hose, thermometer, and even two pads of pH paper. I
had to buy a vigreux column separately, but it was only like $12. Then I just got a 1000 mL two-neck flask for like $20, which gives me three flasks
(one of which has two necks), and a vacuum distillation setup with thermometer for under $60.
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NEMO-Chemistry
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Thanks, sounds like the price dosnt reflect the quality in this case!
I have a bit more faith in giving it a go now.
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aga
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| Quote: | | I have a bit more faith in giving it a go now. |
As always, safety first, so take enough precautions so that you can survive intact if the entire thing implodes then explodes, spraying you with razor
sharp glass shards.
Unlikely to happen, but always be prepared.
Personally i slowly (~40 secs) cranked it down to 100mBar with the entire rig in the fume hood with the 'hood door closed, listening for any *plink*
noises.
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NEMO-Chemistry
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No fume hood yet, but a screen would seem in order until i can one built! Doubt i would hear a plink from 300m lol.
I had planned on double glazed window panes for the front (have some from a skip), but i am now thinking the polly carbonate stuff at least for the
outside pane.
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Cabalaba
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I think most of us buy cheap items on eBay.
I wouldn't have a lab without the savings it provides.
Point being, know you glassware and project.
I still use an old scuffed 2L Ace RB, but won't be heating phosphoric acid in it anytime soon.
Mistakes with chemicals can change lives. And sadly, they're often preventable. Even having a fume hood isn't enough if you don't know enough about
it.
Not trying to frighten you, I hope you distill the hell out of whatever you want, just proper warning from an ass who learned a few things the hard
way.
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NEMO-Chemistry
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I am blessed with the cowards gene, plus i am not generally a risk taker. But its a fair pont that for many ebay and cheap glass it what makes the
hobby accessible.
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