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Topic: Stuck on HCL...  (Read 23033 times)

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Offline orgopete

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Re: Stuck on HCL...
« Reply #15 on: August 03, 2010, 03:10:15 PM »
Well, I am still stuck on why anyone would want to make HCl. You can buy it in the hardware store. If he said it was to make sodium chloride, I would still remain skeptical. There are things I can imagine making, but something that requires chlorine or sulfuric acid, and we scared off someone who wanted a safe nail polish remover? Really now, some people gave that poster a hard time and this person wants to make HCl? Seriously?
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Offline nj_bartel

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Re: Stuck on HCL...
« Reply #16 on: August 03, 2010, 03:28:55 PM »
The hardware stuff is usually stuck with stuff like iron impurities, so if you're working with something that iron's going to catalytically mess up...  That's not the case here, but just a point  :P

Offline Borek

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Re: Stuck on HCL...
« Reply #17 on: August 03, 2010, 05:22:30 PM »
Gaseous, compressed, in cylinders? Nobody sane will buy this stuff when they need a solution. Buy 38% solution and dilute.
This is crap, I used gaseous HCl all the time in my pilot plant with absolutely no problems. I used it to make solutions in ethyl acetate, ethanol etc.

As far as I can tell we are talking about water solution. When in need of water solution, would you start with gaseous HCl?
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Offline discodermolide

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Re: Stuck on HCL...
« Reply #18 on: August 04, 2010, 05:51:05 AM »
Gaseous, compressed, in cylinders? Nobody sane will buy this stuff when they need a solution. Buy 38% solution and dilute.
This is crap, I used gaseous HCl all the time in my pilot plant with absolutely no problems. I used it to make solutions in ethyl acetate, ethanol etc.

As far as I can tell we are talking about water solution. When in need of water solution, would you start with gaseous HCl?

Depends on the reaction I am doing at the time
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Offline discodermolide

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Re: Stuck on HCL...
« Reply #19 on: September 04, 2010, 12:07:08 PM »
@ Discodermolide: Don´t tell such stories to the newbies here. Gaseous HCl is very nasty stuff.  I have also experience with CO, SO2, ethylene, H2 of course and also phosgene, all in gas form. It´s always a pain...

Note I said Pilot plant
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Offline orgopete

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Re: Stuck on HCL...
« Reply #20 on: September 04, 2010, 04:23:32 PM »
@ Discodermolide: Don´t tell such stories to the newbies here. Gaseous HCl is very nasty stuff.  I have also experience with CO, SO2, ethylene, H2 of course and also phosgene, all in gas form. It´s always a pain...

Note I said Pilot plant

I am with Discordermolide here, except for the Pilot Plant requirement. I always liked catalytic hydrogenations as the work-up was always easy, filter and evaporate. I don't want to generalize, as it depends on equipment at your disposal, experience, etc, but I can imagine it being a pain (HF, SF4) or a pleasure (H2, I can imagine others, though I haven't used them).

I don't mean to hihack this thread. I still don't understand why the poster escapes criticism for wanting to make HCl gas in the first place, let alone using it. How many of you that used HCl gas, made it? I am more than skeptical.
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Offline discodermolide

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Re: Stuck on HCL...
« Reply #21 on: September 04, 2010, 11:30:08 PM »
Never made it, always bought it!
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Offline nj_bartel

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Re: Stuck on HCL...
« Reply #22 on: September 06, 2010, 05:06:52 PM »
@ Discodermolide: Don´t tell such stories to the newbies here. Gaseous HCl is very nasty stuff.  I have also experience with CO, SO2, ethylene, H2 of course and also phosgene, all in gas form. It´s always a pain...

Note I said Pilot plant

I am with Discordermolide here, except for the Pilot Plant requirement. I always liked catalytic hydrogenations as the work-up was always easy, filter and evaporate. I don't want to generalize, as it depends on equipment at your disposal, experience, etc, but I can imagine it being a pain (HF, SF4) or a pleasure (H2, I can imagine others, though I haven't used them).

I don't mean to hihack this thread. I still don't understand why the poster escapes criticism for wanting to make HCl gas in the first place, let alone using it. How many of you that used HCl gas, made it? I am more than skeptical.

I have, but just for home chlorinei synth

Offline demoninatutu

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Re: Stuck on HCL...
« Reply #23 on: September 06, 2010, 10:50:06 PM »
nj_bartel and orgopete are right to be concerned about this request. dudeman's planning to use gaseous HCl (which is very nasty stuff in inexperienced hands) without understanding any of the basics. When asked for more explanation of what he's doing, he dodged the question twice meaning that a) what he's doing isn't legit or b) he's one of those people that don't want to listen to advice. Either way, he should be told to steer well clear of HCl gas.

Offline dudeman

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Re: Stuck on HCL...
« Reply #24 on: September 12, 2010, 05:03:25 AM »
Hey guys! Back with an update... I got my 32% HCL in the mail and did some experiments... first of all... When I opened the box and took the bottle out they were wrapped in some absorbent (chemically inert to hcl) cloth. They were right to wrap the bottles in cloth because it sure did reek of HCL when I smelt the cloth. It burns... I'm guessing they didn't douse the bottles in HCL before they packed them so that must mean the HCL lost some of its potency. I'd like to think it lost about 1% maybe? Anyways... Onto my experiment... (not being illegal)

I tried refluxing a 20% HCL solution on its own. I had all of the safety precautions in full effect...

Results...

  Refluxing HCL with a normal condenser will result in hydrogen chloride escaping. I think this is due to lack of surface area within the condenser...

Since HC has a lower bp than h2o wouldn't more hc boil out of the mixture than water? or is the world perfect and a perfect amount of each boils out at the same time? this is what I'm stuck on...

Offline discodermolide

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Re: Stuck on HCL...
« Reply #25 on: September 12, 2010, 05:55:33 AM »
Hey guys! Back with an update... I got my 32% HCL in the mail and did some experiments... first of all... When I opened the box and took the bottle out they were wrapped in some absorbent (chemically inert to hcl) cloth. They were right to wrap the bottles in cloth because it sure did reek of HCL when I smelt the cloth. It burns... I'm guessing they didn't douse the bottles in HCL before they packed them so that must mean the HCL lost some of its potency. I'd like to think it lost about 1% maybe? Anyways... Onto my experiment... (not being illegal)

I tried refluxing a 20% HCL solution on its own. I had all of the safety precautions in full effect...

Results...

  Refluxing HCL with a normal condenser will result in hydrogen chloride escaping. I think this is due to lack of surface area within the condenser...

Since HC has a lower bp than h2o wouldn't more hc boil out of the mixture than water? or is the world perfect and a perfect amount of each boils out at the same time? this is what I'm stuck on...

Hydrogen chloride has a Bpt of –85.1 °C. So it is nothing to do with the condenser surface area. I think you are wasting your time.
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Offline orgopete

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Re: Stuck on HCL...
« Reply #26 on: September 12, 2010, 10:23:00 AM »
Roughly, constant boiling HCl is 18% while conc HCl is 37% (I don't remember the actual values). When you reflux, there isn't enough water to absorb the HCl as the higher temperature.

There had been an earlier post in which someone advocated refluxing an ester in conc HCl. At the time, I thought about making a note about the HCl pouring out if you do this, but since the concept was basically correct, it would hydrolyze the ester, I let it go. Here is why you don't want to just do this. If you want to reflux HCl, dilute it to constant boiling HCl (~6N) first.
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Offline MissPhosgene

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Re: Stuck on HCL...
« Reply #27 on: September 12, 2010, 11:07:11 AM »
Dudeman, all I can say is you better have a legit fume hood.
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Offline dudeman

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Re: Stuck on HCL...
« Reply #28 on: September 12, 2010, 02:26:29 PM »
Dudeman, all I can say is you better have a legit fume hood.

lame useless comment...

Offline dudeman

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Re: Stuck on HCL...
« Reply #29 on: September 12, 2010, 02:35:01 PM »
Roughly, constant boiling HCl is 18% while conc HCl is 37% (I don't remember the actual values). When you reflux, there isn't enough water to absorb the HCl as the higher temperature.

There had been an earlier post in which someone advocated refluxing an ester in conc HCl. At the time, I thought about making a note about the HCl pouring out if you do this, but since the concept was basically correct, it would hydrolyze the ester, I let it go. Here is why you don't want to just do this. If you want to reflux HCl, dilute it to constant boiling HCl (~6N) first.

Awesome... So I think what your saying is at 18% concentration the HC escaping from the water will have enough water vapor around to become HCL again in the condenser... Concentrated HCL cannot be refluxed without loss of Hydrogen Chloride due to the ratio of HC to water in the condenser. at 18% the ratio is balanced and little HC escapes from the solution?

So regardless of surface area in my condenser the HCL will suffer loss of potency when the concentration is above 18%...

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