Sciencemadness Discussion Board

keten lamp

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Sauron - 30-8-2007 at 16:43

Not for you, chemicalpower.

You are attempting to manufacture Acetic Anhydride to supply to criminals in your country (Pakistan) to process opium into heroin (or morphine from opium into heroin). You said as much yourself in a PM to me.

As this is not amateur science, I will not help you with your illegal activity.


[Edited on 31-8-2007 by Sauron]

chemicalpowerII - 31-8-2007 at 03:34

Dear Sir,
I am not trying to help any criminals or supplying anything. i dont think making cellulose acetate is a crime. meanwhile if you feel like not sharing your findings its ok but you should not put things up on the main forum that you are not clear about and maybe they can create a lot of problems for others.
take care

Sauron - 31-8-2007 at 04:00

Liar.

Cellulose acetate was the Iranian's story. You TOLD me what you are up to, and I told you to get the hell away from me. You failed to do so. Take the consequences.

The Iranian (hector) at least made up a cover story, even though having to make cellulose acetate to manufacture glue was never a really plausible notion. It was sufficient to give him the benefit of the doubt. For a while anyway.

Your story (mostly expressed in PMs) was that you are not a chemist but in debt to a loan shark and the shark will let you pay him off in Ac2O, if you can make a lot of it fast.

You never in all those months said one word about cellulose acetate.

Ac2O is tightly controlled in your country due to the burgeoning south Asian heroin traffic, which NATO forces are fighting in Afghanistan next door to you trying to suppress.

If you WERE (arguendo) making cellulose acetate you could just buy acetic anhydride or acetyl chloride, or that matter, cellulose acetate, itself a cheap commodity.

Finally you had the audacity to mention heoin in a PM to me, in context of a color test you subjected your product to, you said the heoin turned black.

GET LOST!

I am posting this so you cannot misrepresent yourself to others as you did to me, wasting my time.

[Edited on 1-9-2007 by Sauron]

hector2000 - 1-9-2007 at 09:25

Mr sauron i promise to god that i didnt make heroin
i forget our glue and anhydrid (we were bankrupt)
now i have small game net in tehran
thanks god every thing is ok
God keep you
bye

[Edited on 2-9-2007 by hector2000]

Sauron - 1-9-2007 at 16:20

Nice to hear from you, @hector.

No one said you made heroin.

Just that the cellulose acetate thing did not appear to make economic sense.

Best wishes with your new business.

Fashist - 25-11-2007 at 09:34

Quote:
Originally posted by Sauron
Put that question aside for the moment.

Here are two US patents from 1930s.

First one says vinyl acetate + acetic acid over conc sulfuric acid as catalyst, gives acetaldehyde and acetic anhydride. Claims 77% conversion and 95% recovery of the anhydride formed. No PdCl2 required.

Other catalysts suggested include phosphoric acid, sulfonic acids like p-toluenesulfonic acid (the example they give is benzenesulfonic acid), etc. as I know you have a problem with sulfuric acid.

This would be very cheap and easy. No acetyl chloride needed. No PdCl2 needed. You should try this. No sodium acetate needed. So no more 3 day drying oven.

Don't thank me, thank @S.C.Wack who pointed these out in another thread.

[Edited on 25-3-2007 by Sauron]

Hmm
Interesting Method
No Result?

Sauron - 26-11-2007 at 03:41

Well, I now have a jug of VA monomer (syabilized) sitting under my desk but, my "client" at that time, has evaporated and says he is out of the acetate glue business in Iran. So I have not yet followed up on this. The fellow in Pakistan who tried it got nowhere but, events demonstrated that his skills were meager. So, inconclusive.

Hardly matters since there are other and more reliable proven methods. No need to chase an acient patent is there?

Fleaker - 26-11-2007 at 09:28

I'd be interested in hearing the results. The acetone pyrolysis method I have tried, and it could probably make several liters per day, however it is dangerous. To me, ketene+700C tube furnace+any air leak == explosion.

Eclectic - 26-11-2007 at 11:08

Well yes, but if you can't manage preventing an air leak in your apparatus, you have no business doing this kind of organic chemistry and working with flammable solvents anyway. :o

Sauron - 26-11-2007 at 11:28

My argument against this is ketene's toxicity. Want to deal with something phosgene-like at elevated temps? Not me.

jimmyboy - 26-11-2007 at 12:16

I have no clue why you don't just synth benzoyl chloride - chlorinate some benzaldehyde.. done.. and it won't kill you if you get a noseful

Fleaker - 26-11-2007 at 13:04

Quote:
Originally posted by Eclectic
Well yes, but if you can't manage preventing an air leak in your apparatus, you have no business doing this kind of organic chemistry and working with flammable solvents anyway. :o


http://www.sciencemadness.org/talk/viewthread.php?tid=7447

According to NERV, I apparently can't do this. I didn't tighten the flanges down properly when we made the reaction tube. Definitely was a fire coming out of the acetone input end of the tube! :P

Personally, I think it is much more viable a method than the ketene lamp.

Eclectic - 26-11-2007 at 13:13

You could start with acetylene, acetic acid, and H2SO4/Hg catalyst.

It would be essentially the same process, and you wouldn't need to get vinyl acetate. ;)

Compassion Please!

MagicJigPipe - 26-11-2007 at 20:24

Oh c'mon, help him repay his loan shark. If these loan sharks are in any way like the ones in the movies (ha!) then his life is at stake. Everyone makes mistakes.

**Response to Sauron's next post (so I don't keep adding non infomative posts)**

I was only half serious. Jokingly serious.


[Edited on 26-11-2007 by MagicJigPipe]

Sauron - 26-11-2007 at 20:37

That guy is long gone, his story reeked, he was clueless, and if he was telling the truth, the shark has probably boiled him in pig fat by now.

In any case, moot.

Fashist - 27-11-2007 at 00:40

Quote:
Originally posted by Eclectic
You could start with acetylene, acetic acid, and H2SO4/Hg catalyst.
It would be essentially the same process, and you wouldn't need to get vinyl acetate. ;)

Plz.Explain more.
Thx


[Edited on 27-11-2007 by Fashist]

WizardX - 27-11-2007 at 01:02

Quote:
Originally posted by Fashist
Quote:
Originally posted by Eclectic
You could start with acetylene, acetic acid, and H2SO4/Hg catalyst.
It would be essentially the same process, and you wouldn't need to get vinyl acetate. ;)

Plz.Explain more.
Thx
Mr sauron What is Glue problem?


3. Hydration of Alkynes and Tautomerism http://www.cem.msu.edu/~reusch/VirtualText/addyne1.htm#add3

MagicJigPipe - 27-11-2007 at 10:34

Sorry, I hope I didn't raise him from the dead Sauron.

Sauron - 27-11-2007 at 10:46

No, he's all right. He's Iranian. The one I was referring to was a Paki.

I'm just not very interested in this vinyl acetate process any more. There are tried and true ways to make acetyl chloride. Anyway Hector buys his acetyl chloride in 200 L drums from Merck for $6 a liter, and that is a lot cheaper than I can make it from TCT or benzoyl chloride.

MagicJigPipe - 27-11-2007 at 11:45

Damn, I have a feeling THAT, of all things, would raise a red flag.

Sauron - 27-11-2007 at 20:06

Why?

The fellow explained why he was in need of Ac2) in a qty of 50 L/day - acetylation of cellulose. He was reacting acetyl chloride with sodium acetate. He was having technical problems and seeking a cheaper less troublesome method to produce 50 L acetic anhydride a day. Now, that is how this thread got started.

I reckon, if he was up to no good, he would not be pinching pennies.

Ac2O cannot be purchased legally in his country. For reasons that ought to be obvious.

In THIS country, neither Ac2O nor acetyl chloride can be purchased without special permits, hard to obtain. So I am rather jealous of $6 a liter AcCl. (Merck, for synthesis.)

MagicJigPipe - 27-11-2007 at 21:34

Well, I suppose I meant... People lie and govts are paranoid. Rightly so in certain areas.

Eclectic - 27-11-2007 at 23:28

And paranoid governments lie...:P

Sauron - 28-11-2007 at 02:32

I do not believe that Hector2000 aka fashist is here as a representative of his government, any more than MJP is here as a representative of the US government.

Fashist - 28-11-2007 at 03:37

Unfortunately Merck dont sale any chemical to iran(germany cut it trade with iran)
We are alone without any friend.
Any way the game net here has no gain i should close that.
I now nobody trust my idea for making celloluse acetate.but i dont lie.(god know)
I see the rise of making ketene system in the other topic.
Very very nice and intersting.
But i think i cant buy tube heater here.
I want to buy tube heater from this site:
http://www.lentonfurnaces.com/content.asp?id=3&doc=16
What is your idea?is good system?
Mr sauron why you dont working on va method(perhaps va method has problem :P )
I am Amorous the new ketene system(http://www.sciencemadness.org/talk/viewthread.php?tid=7447)
What is your idea
Excuse me for my bad english
thx


[Edited on 28-11-2007 by Fashist]

garage chemist - 28-11-2007 at 04:30

A tube heater for the laboratory is probably best made by oneself. New tube furnaces are generally very expensive.
I am in the process of doing this, expect a documentation when I'm done.
Basically, you wind heating wire around a ceramic tube, coat it with insulation paste (a simple MgO+Al2O3 mix), surround the thing with thermal insulation, and put it in a housing. Add an electronic thermometer with its thermocouple inside the tube and a thyristor circuit for regulating the heating power.
Use a quartz (or even stainless steel, for ketene) tube inside the ceramic tube as the working tube in which the cracking of acetone will occur.

Sauron - 28-11-2007 at 04:36

The VA method, is not a high priority for me. At the present I am preoccupied with trying to get my large fume hood installed (main obstacle is $$$) and also getting my Parr autoclave shipped from California.

Fashist - 28-11-2007 at 05:16

Quote:
Originally posted by Sauron
The VA method, is not a high priority for me. At the present I am preoccupied with trying to get my large fume hood installed (main obstacle is $$$) and also getting my Parr autoclave shipped from California.

I Hope you success in hood setup.
I have not important news:probably i will come to thai(pataya)3 mounth later. :P
Mr sauron Do you work with your tube heater and new ketene method?
God keep you.
Quote:
Originally posted by garage chemist
A tube heater for the laboratory is probably best made by oneself. New tube furnaces are generally very expensive.
I am in the process of doing this, expect a documentation when I'm done.
Basically, you wind heating wire around a ceramic tube, coat it with insulation paste (a simple MgO+Al2O3 mix), surround the thing with thermal insulation, and put it in a housing. Add an electronic thermometer with its thermocouple inside the tube and a thyristor circuit for regulating the heating power.
Use a quartz (or even stainless steel, for ketene) tube inside the ceramic tube as the working tube in which the cracking of acetone will occur.


you are very Clever and you have Perseverance
bravo
sure your system will work well. but i think better i buy one tube heater(i write the company link before)
I think the result will be better if we use of copper tube.what is your idea?
i am Amorous Mr NERV Ketene system.
Do you test your anhydrid with water?
what is purity?are you Acquiescent?
i think i should start celloluse acetate business in small Quantity.
thank you




[Edited on 28-11-2007 by Fashist]

MagicJigPipe - 28-11-2007 at 08:35

I happen to be very amorous for him as well!
God keep you!

*laughing uncontrollably*

Fashist - 28-11-2007 at 12:47

I dont Know why Nobody answer my questions?
I think I am Buffoon for most of user like Mr MagicJigPipe and Other
Why?really why?
I think i can explain my problem here.not for laughing.
This is Great Request?
Thx

MagicJigPipe - 28-11-2007 at 14:38

I'm sorry, it's just that amorous, in English, usually implies strong feelings of love (sometimes even a sexual connotation) and that is why I was laughing.

I have nothing against you nor am I making light of your situation. I understand English is a difficult language to learn.

So, please accept my apologies if I offended you. Just don't use the word amorous again unless you're talking about your wife or girlfriend!


** second edit**

Sauron, could you please unblock me on U2U? I need to ask you a question.

[Edited on 28-11-2007 by MagicJigPipe]

[Edited on 28-11-2007 by MagicJigPipe]

Sauron - 28-11-2007 at 20:17

Fashist (Hector), I have not done anything with my tube furnace but, I really do not want to work with ketene. It is a carcinogen. Cancer may get me one of these years but I do not wish to hasten the process just to make a little Ac2O.

There are much safer ways to do so.

Fashist - 28-11-2007 at 23:27

Excuse me.
Always I translate My word by Online Dictionary(and has some Technical Problem)
Mr sauron one questin? may copper tube make better than quartz tube(ketene)?
If we use of copper tube the temp should be 700c?
thx

Sauron - 29-11-2007 at 00:03

I think I gave you a file with everything I have on kete already, fashist. I believe what you asked is answered in there. There's nothing else to add.

Fashist - 29-11-2007 at 00:06

Yes it is True.
Excuse Me.

JohnWW - 29-11-2007 at 15:01

Ebook - Ketenes: http://rapidshare.com/files/35523052/ket.rar 6 Mb

not_important - 29-11-2007 at 23:52

Copper tubing works well for making ketene from acetone, copper does not catalyse the decomposition of ketene.

I posted a PDF that is a chem. eng. project to make acetic anhydride from acetone and acetic acid. It discusses some of the concerns in making an efficient convertion, the best way to absorbe the ketene, and other things you need to deal with when doing this in a large scale lab or pilot plant setting.

Contact time, temperature, and temperature distribution are all important to a successful process. The low the conversion in a pass the higher the overall yield, with recycling of unreacted acetone. Quick quenching of the gases is also important, that study above discusses this.


Also see :

Ketene Production and Utilization Experimental Study
Morey, Ind. Eng. Chem., 31, No. 9: September 1939 1129-1132
DOI: 10.1021/ie50357a016

including information on the reaction tube they used.

JIC here's that project, seeing as it's a small file.


[Edited on 30-11-2007 by not_important]

Attachment: Project00.1.pdf (73kB)
This file has been downloaded 1185 times


Fashist - 30-11-2007 at 00:00

Mr not important thanks
I have one request and Two question. :o
(?)If we use of copper tube again we will have DUST of carbon(in the tube)?
(?)What temp require if we use of copper tube (700 or more?)
(!)I want to buy one tube heater(from lenton company) but it is very expensive(3000$)do you know cheaper source?
Thanks

[Edited on 30-11-2007 by Fashist]

not_important - 30-11-2007 at 00:23

In the Ind Eng Chem article they used temperatures in the range of 580-650 C or so. While 700 C is often used, you need good regulation and heat distribution to avoid overheating the gases.

HOWEVER - there is no turnkey solution, you can't read some papers and expect something like a DIY kit. Experimentation will be needed to optimise your plant, and maybe even to get it to given a useful output at first. Things like formation of carbon are going to depend on a number of factors, if I was good predicting what will happen in your case I'd retired off of the stock market and betting winnings long ago.

I'm not into buying pilot plant scale equipment right now, I expect that making your own might be the cheapest given your circumstances.\

While this is the acetic acid to acetic anhydride route, which while it goer through ketene is a bit different, this recent study for an industrial plant may prove useful:

http://www.lassc.ulg.ac.be/bibli/heyen-2003-1.pdf

Fleaker - 30-11-2007 at 09:57

Having actually done this before (you saw the pictures which NERV and I took), I can say copper would be suitable. A 40cm or so long by 2.5cm inner diameter stainless tube packed with copper wool (to increase contact time) was what we used and we operated at 700*C. Yield was ~33% or something around there. There was zero carbon dust formation whatsoever, it was very clean.

If you have a big 20L flask and are boiling a lot of acetone, this method would work well, it would make a lot of Ac2O. It is still necessary to fraction your Ac2O from your acetic acid. Also, you might remember the round bottom flask on the output (ketene) end of the tube? It would be really smart to have it setup so any acetone that condenses in the condensers and collects in the flask would be rerouted into the boiling flask on the input side.

Bromide - 1-12-2007 at 15:43

Quote:
Originally posted by Sauron
Fashist (Hector), I have not done anything with my tube furnace but, I really do not want to work with ketene. It is a carcinogen. Cancer may get me one of these years but I do not wish to hasten the process just to make a little Ac2O.

There are much safer ways to do so.


Sauron, what leads you to assert that ketene is a carcinogen? I ask because you've raised this concern in a couple of previous posts, but my casual perusal of Google, etc., have all lead to documents claiming that ketene is in fact not suspected to be a carcinogen (although it is known to be toxic, of course--see here, for example).

My question is not meant to be impertinent or a challenge; I'm simply interested to learn what additional insight you have into ketene's carcinogenicity.

not_important - 1-12-2007 at 21:03

When I made my ketene generator I got some carbon at first, this appeared to be from too slow of a flow through the tube. Higher flow rates had no carbon formation when run for several days at a time.

The highest yields come with fairly low conversion of acetone, the overall yield is based on recycling the acetone. The conditions that give lower per-pass conversion also suppress side reactions.

And here, thanks to solo, is the research paper, for those without reference section access. While their target is butyl acetate and not acetic anhydride, the ketene production is the same.

Note that they used two absorption towers, plus a bubbler filled with aniline in benzene. The project on anhydride production recommends holding the acetic acid/ketene reaction towers at 80 C.

Attachment: Ketene Production and Utilization Experimental Study.pdf (518kB)
This file has been downloaded 1069 times


Fashist - 1-12-2007 at 22:57

Thanks Mr Not_Important
Very useful Article.
In this Article there is unintelligible Image of Keten System.
May you simplify it for Anhydrid?
Again thanks.Bravo
I am building My ketene System But i Need to your Advise.
According Mr Nerv and Mr garage chemist System
-My ballon is 10lit and made of aluminium(for boiling acetone)
-My tube made of three part.two linker with 1cm diameter and one part with 3.5cm diameter.all af them made of copper.
Tube heater Provide 700c(it element made of ni/cr)
- acetone collector(3 way ballon) made of aluminium 5lit
- condenser made of copper 1meter
-cylinder glass container 4lit
What is your idea?
Every thing is ok?
Thanks


[Edited on 2-12-2007 by Fashist]

Attachment: Untitled-1.zip (407kB)
This file has been downloaded 572 times


not_important - 2-12-2007 at 01:13

No. It can't be made simpler, unless your goal is to make 50 ml of anhydride. For large scale production the apparatus will be more complex, at least if you want any sort of decent yield.

You need to read the apparatus section in the PDF, between that and the drawing I found it very clear. You also need to reread Project00.1.pdf as well.

Your tube in the furnace is too large in diameter. Both of those documents make it clear that quick and complete heating must be do, which a simple large diameter tube will not do. Both documents also make it clear that the gases exiting the furnace must be quickly cooled. the newer document does this using a water spray on the outside of the tube while the anhydride plant does this using a spray of acetic acid, acetic anhydride, and acetone.

Ketene does not react extremely quickly with neutral and mildly acidic compounds, thorough contact must be had for sufficient time. A single simple absorber will likely have much unreacted ketene escaping it, resulting in both low yields and the problem of lots of free ketene drifting about.

Expect only 10 to 20 percent of the acetone fed through the furnace to be converted to ketene, so your condensing receiver must be nearly as large as the boiler.

You'll also need to worry about oxidation of the outside of the copper tubing in the furnace; the more recent reference solved this by driving the copper tube through a stainless steel pipe forming a jacket for the copper.

Fashist - 2-12-2007 at 01:33

Valuable advise.thanks
My tube in the furnace is too large because my pressure increased(my acetone boiler is 10lit then more acetone will come.)what size is suitable for this system?
in the picture my cooler system is near to my condenser.isnt it?
Very good advise for cover of copper but difficult to do.
Mr not important please advise me more for this system
i am sending your patent for expert translate(this translate is very expensive 10$ per page)


[Edited on 2-12-2007 by Fashist]

not_important - 2-12-2007 at 10:07

You only have to cover the copper tube that is in the furnace. The items needed to do so were a steel pipe, some hydrochloric acid, and a hammer.

Your proposed system with a 10 liter boiler is five times as large as the example large scale lab production unit in "Ketene Production and Utilization..." This should tell you some time - if you wish to make a proof-of-concept apparatus, don't make it so large and you can make it a bit simpler, if you want large scale production then it will be more complicated.

As an example, a simple proof of concept setup would not attempt a high volume of acetone boil-off. It could have a large boiler as a convenience to allow it to run for many hours without stopping to refill, just use a fairly low boil rate. But if you want to make a lot of anhydride per hour you will need multiple tubes with manifolds at each end of the oven to distribute and collect the gases.

Very quick cooling of the exit gases to 200 C or lower is needed to keep yields up. In "Ketene Production..." this was done by spraying water on the exit side of the copper tube, note that they still had the acetone condenser a bit further on. In the "Project00" example this was to be done by very quickly quenching the hot gases in the absorption tower with cool liquid containing acetone that would vapourise.

On a small scale a simple absorption method is OK, provided you have a good train of scrubbers to catch the unused ketene. Low yields, possibly high backpressures. On a large scale you need proper absorption towers designed for low backpressures while providing good contact between liquid and gas.

On a large scale you are going to need to address the flammable non-condensible gases exiting the absorption section.

Sorry I can't help with translations, my Pārsi is pretty much limited to asking where to eat and "do you know someone who speaks Komi or Strine?"

Fashist - 2-12-2007 at 10:18

Oh My God.Very Difficult.
If I use this system(according to my picture)probably i will have 100ml anhydrid per Day or little more.
What is your advise(what boiler?how long tube?..)
I want to make 5-10 lit anhydrid per day.what is your suggestion?
Mr not important really thanks

Quote:
Originally posted by not_important
Sorry I can't help with translations, my Pārsi is pretty much limited to asking where to eat and "do you know someone who speaks Komi or Strine?"

This Mean That i Dont ask Question?

[Edited on 2-12-2007 by Fashist]

WizardX - 2-12-2007 at 16:53

KETENE http://www.orgsyn.org/orgsyn/prep.asp?prep=cv1p0330

not_important - 2-12-2007 at 17:56

Quote:
Originally posted by WizardX
KETENE http://www.orgsyn.org/orgsyn/prep.asp?prep=cv1p0330


Very true, but if you had read the thread you would have seen that it was discussed early on, and is not suitable for the application in question. Too small of a production rate, the filament requires frequent cleaning, and the apparatus is fragile.

Quote:
Originally posted by Fashist
Oh My God.Very Difficult.
If I use this system(according to my picture)probably i will have 100ml anhydrid per Day or little more.
What is your advise(what boiler?how long tube?..)
I want to make 5-10 lit anhydrid per day.what is your suggestion?


Things like the tube length a somewhat dependent on flow rate and heat transfer. Too long of a time at the high temperatures leads to excessive breakdown of the ketene.

I'd start with that "Ketene Production..." model for the tube, go ahead and use your boiler. Carefully control the heat input to the boiler, do several test runs at a given boil-up rate and tube temperature, figure out anhydride yield and acetone boil-up rate which will give you the approximate flow velocity through the tube. Repeat with a bit higher heat input to the boiler, and repeat again until the yield drops off or excessive amount of acetone distill (remember than maybe 20% will be converted and likely less).

And put a real effective absorption train after the anhydride absorber, you must keep ketene from getting out.

Once you've done that you knw the basic parameters for your tube furnace. You can then build a larger oven and run multiple tubes through it, with manafolds at each end so a single boiler can feed them and their output is collected for feeding to the absorption unit for making anhydride.

You will likely need to refine the absorption/quenching section to optimise yields. This section will resemble a fractionating column, as that gives good contact between gas and liquid.

Outside of that I've already given you all the advice I have - it's in those PDFs and test books that cover the processes used.

Quote:

Quote:
Originally posted by not_important
Sorry I can't help with translations, my Pārsi is pretty much limited to asking where to eat and "do you know someone who speaks Komi or Strine?"

This Mean That i Dont ask Question?


No, it means I can't do the translations for you. I suspect you already know good places to eat, so that exhausts my Pārsi :-)

Fashist - 2-12-2007 at 23:47

Thanks Mr not_important
If i use single boiler and multiple copper tube then i must use Multiple condenser and Multiple container for anhydrid?

Quote:
Originally posted by not_important
No, it means I can't do the translations for you. I suspect you already know good places to eat, so that exhausts my Pārsi :-)

This is difficult for understand your PHRASE.
because there is diffrent between Farsi phrase and english
again thanks(i dont konw better word for thanks)
Mr sauron you have no idea?(You are my master)

[Edited on 2-12-2007 by Fashist]

not_important - 3-12-2007 at 00:08

No, a manifold is a pipe with multiple connection to other pipes, for the purpose of distributing to those other pipes or collecting from them. Often the manifold is larger than the feeder pipe, because it handles a larger flow.

So one largish pipe from the boiling has a number of small tube connected to it. The smaller tubes are in some sort of an array, their bodies in parallel and adjacent but separated a bit. Their other ends all connect to a second manifold that combines the flows and takes it to the quencher. The second, hot side, manifold would likely be smaller than the boiler side one, because you want to minimise the time the gases remain hot, and thus want high flow rates.

Read the Project00 file - for larger scale production you don't want to condense the acetone out first, but instead quench the hot gases with a liquid make of acetic acid, acetic anhydride, and acetone. Acetone condensation and recovery is done after that stage.

As I said several posts ago, my Farsi is limited to being able to ask directions for places to get food. It will not suffice in translating the material in this thread.

Fashist - 3-12-2007 at 00:53

Mr not important really thanks
This is very good that you know a simple Farsi SENTENCE(i know members that believe farsi is arabi and they dont know what is farsi!) :o
Mr not important i understand english No need for farsi.
you say true but you should accept that your two patent is very professional and this is difficult to underestant fast and complete.
your suggestion is very interesting for me.
according to your suggestion I realized this image
Good idea?



[Edited on 3-12-2007 by Fashist]

Attachment: Untitled-1.zip (24kB)
This file has been downloaded 678 times


WizardX - 3-12-2007 at 03:17

Quote:
Originally posted by not_important
Quote:
Originally posted by WizardX
KETENE http://www.orgsyn.org/orgsyn/prep.asp?prep=cv1p0330


Very true, but if you had read the thread you would have seen that it was discussed early on, and is not suitable for the application in question. Too small of a production rate, the filament requires frequent cleaning, and the apparatus is fragile.


The apparatus (above link) is not a ketene lamp.

It is a glass combustion tube filled with broken porcelain, and fourteen of the twenty burners of the combustion furnace are lighted (Note 4) and tiles are placed over the lighted burners, which finally must be adjusted to yield a maximum temperature. The first two and last four burners are unused.


Ketene can be generated conveniently by pyrolysis of acetone in a hot tube or over a hot wire in a "ketene lamp," or by pyrolysis of diketene in a hot tube, or by pyrolysis of acetic anhydride. Other methods of preparation have been summarized. It has been shown that diketene cracks quite cleanly to ketene , although some allene and carbon dioxide are formed at the same time.

The most convenient procedures for the preparation of ketene are the present one and the pyrolyses of acetone or acetic ahnydride. The acetone procedure gives ketene at a relatively fast rate (0.45 mole per hour), but it takes considerable adjustment to get optimum conditions, and trouble is sometimes caused by the wire getting coated with carbon. Furthermore, because the efficiency of a given wire coil varies with time, passing through a maximum, frequent calibration of the apparatus is necessary. The acetic anhydride method is even faster (1.31 moles per hour) and uses a readily available chemical. It appears to be the method of choice at this time. The diketene procedure described here is relatively simple and reliable; however, it is relatively slow (0.2 mole per hour) and requires a somewhat less readily available starting material.

http://www.orgsyn.org/orgsyn/prep.asp?prep=CV5P0679

Fashist - 3-12-2007 at 12:09

No idea For My Design?

MagicJigPipe - 3-12-2007 at 14:52

From what I can tell (nothing is labeled) it seems like your design is very similar to the one on orgsyn. What's your reasoning for using 3 combustion tubes? Did I miss something upthread or was this your idea?

I suppose it would increase your surface area in the furnace which would be beneficial if your flow rate was high enough. Whether or not this would be better than a single large tube is beyond me. Seems like it could be though.

I thought I would take a stab at his question since no one else was.

Fashist - 4-12-2007 at 00:25

Mr MajicJigPipe Thanks of your Idea
I send Another picture before.the description of this Picture is similar to that Picture(oldest)
Acording to Mr not important advise i increase surface(for better yield)
the DISTANCE between condenser and exit tube is smaller.
But there is one problem:
I have problem with steel cover for copper tube.(may this work is impossible for copper tube)i should find another cover.
I am still waiting for your idea.
thx

not_important - 4-12-2007 at 01:51

OK, problems with your design

The single tube from the boiler needs to be larger, it should have at least half the cross-sectional area as the sum of the cross-section areas of the heated tubes. Same applies to the single tube collecting the gases from the heated tubes.

Using tall cylinders for absorbing ketene the way you've drawn it will not work well, "Ketene Production..." tells you why right on the 1st page and also gives a better working alternative; I've said this before.

Why is pounding copper pipe through the center of steel pipe impossible? Can you not find steel pipe with an inside diameter very close to the outside diameter of the copper?


--------------------------------------------------

Sorry, WizardX , OrgSyn was offline when I clicked the link and I assumed it was the ketene lamp one. The fragility and desired production rate arguments still hold; the OS example does less that a quarter liter of acetone an hour, while the target is at least five times that.

For scaled up production several heated tubes are needed because using one large tube results in poor heat control.

The chapter on ketenes in Organic Reactions vol 3 has a table of literature reports on making ketene, and I've read other such surveys. In general tubes with packing give lower conversions than plain tubes, there is one report (Rice, Greenberg, Waters, and Vollrath, J. Am. Chem. Soc, 56, 1760 (1934)) of good yields with a packed tube. Rather open packing with high thermal conductivity appears to work as well as plain heated tubes, it has been used with larger diameter tubing but is much more difficult to cobble together ones self.

Fashist - 4-12-2007 at 05:03

Thanks Mr not_important
May send us (Rice, Greenberg, Waters, and Vollrath, J. Am. Chem. Soc, 56, 1760 (1934)).
Using cool tall cylinders will captive ketene and Probably all of ketene will React with acetic acid.this isnt true?(there is effluence part end of tube inside the cylinders)
I am still waiting for your advise.

[Edited on 4-12-2007 by Fashist]

not_important - 4-12-2007 at 06:55

From the first page of "Ketene Production and Utilization Experimental Study"
Quote:
It was found, for instance, that when the ketene-containing gases (freed from most of the acetone) were passed into water through a sintered glass bubbler, considerable ketene escaped absorption. This was even the case when two such bubblers were used in series. The sintered glass disks were an inch in diameter and furnished a very fine spray of bubbles. Aside from the inefficiency of this type of absorption apparatus, additional objection was found in its great resistance to gas flow; the rate at which acetone could be put through the pyrolysis chamber was thus decreased.


They were using bubblers similar to the attached image. The combination of the flow resistance of the fritted glass and
the weight of the liquid in a tall container will cause a lot of back pressure, increasing the likelyhood of actone and ketene leaking out of joints in the apparatus.

This is why they and other larger scale production examples use absorption towers resembling fractionating columns for distillatiom, in the ketene plant project the quencher/absorber is a fractionating column, with acetone and the non-condensible gases leaving as vapour.

23684.jpg - 3kB

Fashist - 4-12-2007 at 07:57

Thanks Mr not important
You say Complete True
I Think the absorption towers use for industrial scale(not 5-10lit anhydrid per day!)
your Point about "the weight of the liquid in a tall container " is true but I think this is
OBVIOUS for above 10 lit container.(my cylinders is 2lit)
The absorption tower is very UNINTELLIGIBLE and very Expensive for making.
i saw someplace that german army in wwii used of similar system(without absorption tower.like my system but ketene react with acetic in SQUARE container not CYLINDER)
Wat is your suggestion (replace for tall container?ballon?..)
May you explain this bubblers more?i think there is variant type of bubbler for buy here.
I think if you explain the complete(with detail.like my picture) system for making 5-10lit anhydrid then my question will end(i know you are tired of my question)





[Edited on 4-12-2007 by Fashist]

Fleaker - 4-12-2007 at 14:02

A carrier gas is very nice to surmount the back pressure problem. I can't recall if we used nitrogen or not for our carrier for the acetone vapour.

Eclectic - 4-12-2007 at 14:09

What about introducing the ketene into the boiler of a refluxing packed fractionating column of acetic acid?

Fashist - 4-12-2007 at 23:34

Mr Fleaker very nice suggestion(Thanks)
What part we should insert nitrogen or argon?
This work has no effect on ketene in heater tube?
If this suggestion work well then large amount of argon or nitrogen needed.

[Edited on 5-12-2007 by Fashist]

Fashist - 5-12-2007 at 04:35

Today I Found many patent for making anhydrid(using co+methyl acetate under pressure)
But these patent use of very expensive componet.
Anybody has better patent?
thx

Attachment: 4544511.pdf (420kB)
This file has been downloaded 844 times


not_important - 5-12-2007 at 08:23

If you think a proper absorption tower is expensive, try pricing what's needed for for that process; 5 to 20 times atmospheric pressure, 150 to 200 C, an acidic environment containing carbon monoxide and iodides. Where are you going to get the high purity carbon monoxide needed? That's an entire plant in itself. If you think an absorption tower is "unintelligible" wait until you see what a carbonylation process is like. And then there is catalyst recovery to deal with.

This is what I believe is the most recent significant version of the general process
http://www.patentstorm.us/patents/5900504-description.html

Processes used in war time generally are not too concerned with being economical, focusing on using readily available feedstock and being quick to construct.

To overcome backpressure you need to increase the pressure on the side feeding into the absorption hardware, that is the boiler and hot tube section. It doesn't matter if you generate the pressure by injecting an inert gas or by running the boiler a little hotter. What's important is that leaks become a bigger problem.

For someone who says it is "impossible" for them to drive one pipe through the inside of another, you sure are unconcerned about putting together a system that runs under pressure, even the relatively low pressure to overcome absorber resistance.

------------------------

The goal is to make 5-10 liters anhydride per day.

The systems with the highest overall yield run at low per-pass conversion rates, 5 to 20 percent of the acetone reaction in a pass, the rest is recirculated. Higher conversion rates result in the formation of products besides ketene, reducing the
overall yield and creating more byproducts.

10 percent conversion per pass means 50 - 100 liters equivalent of acetone,
20 percent is still 25 to 50 liters of acetone boiled off.

With recycling of the acetone the amount used is much less, but you still boil enough to be equivalent to much more acetone without recycling.

Many of the example setups boil off a quarter liter or so per hour, some I've seen can do a liter an hour. The stated goal is roughly 25 to 100 times greater than that of the lab benchtop models.



[Edited on 5-12-2007 by not_important]

Attachment: routes-to-acetic-anhydride-abs.pdf (220kB)
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Fashist - 5-12-2007 at 08:41

Quote:
Originally posted by not_important
For someone who says it is "impossible" for them to drive one pipe through the inside of another, you sure are unconcerned about putting together a system that runs under pressure, even the relatively low pressure to overcome absorber resistance.
[Edited on 5-12-2007 by not_important]

Doesnt Matter. :(

Mr not important i think 1-2lit anhydrid per day is more SUITABLE for our.(less problem)
Again we will have Problem if we want 1-2 lit anhydrid per day?
Mr not important Thank you.

Fashist - 6-12-2007 at 02:57

Mr not important
There is other way for making anhydrid in your article
Oxidation of acetaldehyde using cobalt salt.
May explain more this Method?
I didnt say that this work(insert copper tube in steel tube) is impossible for me.i said this work(cover copper tube with steel.Not steel tube.this work isnt USUAL here.)
I think finding better way for making anhydrid has no Problem and isnt sin.
Thanks



[Edited on 6-12-2007 by Fashist]

Fleaker - 6-12-2007 at 11:29

Unless you're making acetaldehyde from cheap, non-taxed ethanol, it won't be economical. Acetaldehyde has problems of its own (i.e. vapour pressure, toxicity). Might as well buy Ac2O ready made.

JohnWW - 6-12-2007 at 14:01

"Might as well buy Ac2O ready made. "? But the whole reason for this thread is that, in many countries, Ac2O CANNOT be "bought ready made", or at least not without bring oneself to the attention of the Pigs, because of its being a very useful reagent not only for general acetylations (most often to protect reactive -OH and other groups during other reactions), but also in drug synthesis, e.g. making heroin by acetylation of other opioids.

I am frankly sick of the Pigs telling us what drugs we can and cannot take, and scaring parliaments and congresses by means of lies (supposedly backed up by so-called "experts" who are in fact in the pay of alcohol and tobacco interests, who probably also bribe the Pigs) into passing laws to this effect. If drugs were legal, it would completely destroy the lucrative black-market for them, and thereby make them less easily obtainable, not more easily obtainable.

not_important - 6-12-2007 at 23:24

The oxidation of acetaldehyde by air or oxygen using a Mn or Cu-Co catalyst takes place at moderate temperatures and pressures, distinctly lower than the carbonylation process. It does produce and decompose peracetic acid, unless considerable care is take interesting explosions can result. The plant requirements are more demanding that the ketene methods.

And as already said, it takes cheap acetaldehyde to be practical, and acetaldyhde is difficult to ship and work with.

If all you want is a liter a day, then a single tube ketene generator will work, the absorption issue still exists.

Quote:
I think finding better way for making anhydrid has no Problem and isnt sin.

I've no idea what you meant by that. If you think you'll find a better acetic anhydride production method, you're not going to find it floating about here. There's been considerable talk on it, there's several threads full of it, including the digging Sauron did here. If there were a simpler good method it's doubtful it would have gone unused industrially; most of the information has been given to you.

Fashist - 7-12-2007 at 01:56

Quote:
Originally posted by not_important
If all you want is a liter a day, then a single tube ketene generator will work, the absorption issue still exists.

Thanks Mr not important
I said before that i need 5-10 lit per day but i think this is very easy to use 5 apart system(each system make 1 lit per day)because if we want 5-10 in one system then probably we need great professor for invent and operate this system.
as you know most important country cut it trade with iran(like germany,france,...) and many chemical not found here.
the price of all chemical componet increased.(for example
1lit acetyle chloride is 120$) this situation is same for our petrochemical componet for ex the price of acetic acid increaseed.(before .5$ per lit.now 3$per lit if you find)
here we have bad situation.
Mr johnww thanks.
i should say that law for drug changed here.
if you have 20-30gram heroin police can kill you without any TRIBUNAL.they can kill you there without any Time.
I dont want to make drug because i believe the price of this drug provide with life of youg people.
just i want anhydrid for glue.no more.
soon i must delete all of my posts(i hope you underestant why)
thanks


[Edited on 7-12-2007 by Fashist]

not_important - 7-12-2007 at 06:49

Actually the 5 separate systems will have the same degree of complexity with the exception of the manifolds. The absorption step remains the same, both for efficiency (cost) and safety issues. Acetic anhydride was not the typical target of laboratory ketene generators, it is for industrial applications so those are the people you need to look to for information. And they all used packed towers or tall empty towers for their combined quench-absorption step.

Mostly ignored in this discussion is what purification of the acetic anhydride will be needed. In the industrial style continuous version you get three product stream - an acetone one to send back to the boilers, an acetic acid rich one containing acetic anhydride and acetone to send to the quench-absorption unit, and the acetic anhydride product stream. In a small batch system you propose you have to distill the condensed acetone, add the still bottoms to the acetic product, distill that to get the acetone rich cut, the acetic acid rich cut, and the acetic anhydride cut. Two distince operations, one with three steps.

The overall effort to operate will be greater, because you have 5 boilers, tube furnaces, and absorption systems to watch.

Fashist - 9-12-2007 at 23:51

The Reaction between ketene and acetic acid is CALEFACTORY or need heat?(accoring to loshatoliye law)
thx

MagicJigPipe - 11-12-2007 at 02:12

This industrial process apparently does it at 80*C.

Although, I have to admit, they do it very differently than a home chemist would.

Attachment: Project00.1.pdf (73kB)
This file has been downloaded 2161 times


not_important - 11-12-2007 at 02:38

Already posted back on 30-11-2007 at 07:52, and I've refered to it several times since.

Quote:
Originally posted by MagicJigPipe
This industrial process apparently does it at 80*C.

Attachment: Project00.1.pdf (72.55 KiB)

Fashist - 11-12-2007 at 06:22

If this Reaction need heat then why mr Nerv used of ice in his system?
Really if this reaction is CALEFACTORY then the method must be same in all project.
(i know many reaction between gas and liquid then need CHILL no heat!)

[Edited on 11-12-2007 by Fashist]

Fleaker - 11-12-2007 at 09:53

We added ice because a lot ketene and was escaping out of the second wash bottle tower filled with water. We could tell this by the smell. When we added ice to the GAA-filled ''absorber'' there was no ketene out the second water-filled absorber. I can only presume that decreased temperature of GAA lead to more ketene solubility or at least a longer residence time in the GAA. But it also means a slower reaction with the GAA so there is probably a point of diminishing returns. I can not say at what scale it is advantageous to cool or to heat your glacial acetic acid, but for us, we found that the least amount of ketene escaped the system when it was cooled.


Edit: It should be noticed that the Acetic acid never got above 30*C; we did NOT try it hot. I suppose we could have heated our absorption vessel with heating tape and tried it that way. It will probably be better to do it that way.

[Edited on 11-12-2007 by Fleaker]

not_important - 11-12-2007 at 09:58

Quote:
Originally posted by Fashist
If this Reaction need heat then why mr Nerv used of ice in his system?
Really if this reaction is CALEFACTORY then the method must be same in all project.


You can calculate the heat of reaction between ketene and acetic acid, standard textbook chemistry; the heat of formation of ketene given before 1980 or so is not correct.

There are other things besides a reaction being exothermic or endothermic that affect how it goes.

The pilot plant document runs the absorption at about 80 C for several reasons; this was done to get best performance. Cooling the acetic acid with ice won't prevent the reaction from taking place. It may have some effect on the performance of the system, but on a small scale benchtop system that is not out to optimise performance that difference might be unimportant to the operators of the equipment.

Remember the motto of Perl....

WizardX - 11-12-2007 at 16:11

(1) Generation of Ketene With High Quantum Yield by a KrF Laser.


[Edited on 12-12-2007 by WizardX]

Attachment: Generation of Ketene With High Quantum Yield by a KrF Laser.pdf (1.2MB)
This file has been downloaded 761 times


WizardX - 11-12-2007 at 16:22

(2) United States Patent 4455439

In this process for the preparation of ketene by the thermal, catalytic cracking of acetic acid under reduced pressure, the hot cracked gases are cooled to approx. 0° to -10° C. and, in the course thereof, water, unreacted acetic acid and acetic anhydride are condensed. The quantity of acetic acid employed for the thermal cracking reaction should be 0.5 to 2.5 t×hours-1 ×m-3, relative to the volume V of a shell-and-tube heat exchanger through which the cracked gas is passed. The pressure drop in the tubular heat exchanger should be 50 to 150 mbars and the surface/volume ratio should be 60 to 120 m-1

Attachment: United States Patent 4455439.pdf (58kB)
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Fashist - 11-12-2007 at 22:29

Thanks Mr Wizardx
I dont Know Why All Patent About Acetic Anhydrid In http://ep.espacenet.com/ Deleted.!?
Mr Fleaker I want to Use Three Container For Reaction:
First Container Has 30c.
Second Container Has ~5c.
Third Container(Contain Water) 30c

[Edited on 11-12-2007 by Fashist]

not_important - 11-12-2007 at 22:46

Quote:
Originally posted by Fashist
Thanks Mr Wizardx
I dont Know Why All Patent About Acetic Anhydrid In http://ep.espacenet.com/ Deleted.!?
Mr Fleaker I want to Use Three Container For Reaction:
First Container Has 30c.
Second Container Has ~5c.
Third Container(Contain Water) 30c

[Edited on 11-12-2007 by Fashist]


Because you keep spelling it incorrectly :

Quote:
RESULT LIST
Approximately 8981 results found in the Worldwide database for:
Acetic Anhydride in the title or abstract
Only the first 500 results are displayed.


30c ? Chungah? Cullishigay? cups? Congius? Cotyla?

Doesn't sound like the best absorption scheme to me.

Fashist - 11-12-2007 at 23:09

3lit Erlenmeyer flask is My Container.
C=Centigrade.
Probably http://ep.espacenet.com hasproblem With iran(again Terrorist Reason) Because I cant see Abstract or Original document.(My Search Words Was Acetic Anhydrid and Anhydrid Acetic)

not_important - 11-12-2007 at 23:17

Anhydride with an 'e' on the end.

Fashist - 11-12-2007 at 23:51

Ok See these link.
These link have no original or abstract for me.
MANUFACTURE OF ACETIC ANHYDRIDE:
http://v3.espacenet.com/textdoc?DB=EPODOC&IDX=CA702840&a...
MANUFACTURE OF ACETIC ANHYDRIDE:
http://v3.espacenet.com/textdoc?DB=EPODOC&IDX=CA689910&a...
PROCESS FOR THE MANUFACTURE OF ACETIC ANHYDRIDE:
http://v3.espacenet.com/textdoc?DB=EPODOC&IDX=CA487581&a...
MANUFACTURE OF ACETIC ANHYDRIDE:
http://v3.espacenet.com/textdoc?DB=EPODOC&IDX=CA467670&a...
PRODUCTION OF ACETIC ANHYDRIDE:
http://v3.espacenet.com/textdoc?DB=EPODOC&IDX=CA467175&a...
MANUFACTURE OF ACETIC ANHYDRIDE:
http://v3.espacenet.com/textdoc?DB=EPODOC&IDX=CA467174&a...
ACETIC ANHYDRIDE:
http://v3.espacenet.com/textdoc?DB=EPODOC&IDX=CA413976&a...
ACETIC ANHYDRIDE:
http://v3.espacenet.com/textdoc?DB=EPODOC&IDX=CA402110&a...
Enough?

Fashist - 21-12-2007 at 12:08

Anybody Has Idea for This New Schematic?
Acetone Recycle.
thx

Attachment: Untitled-1.zip (42kB)
This file has been downloaded 739 times


Bromide - 21-12-2007 at 15:35

Quote:
Originally posted by Fashist
Ok See these link.
These link have no original or abstract for me.
...
Enough?


It's generally advisable not to ascribe hostile motivations for what can readily be explained by benign factors.

In this case, the links you posted are for patents that are all over 40 years old. Thus the reason why the abstracts and scanned images are unavailable to you has nothing to do with the fact that you are in Iran--rather, they are unavailable to everyone, because they have simply never been scanned or typed into the EPO system. Patents of that vintage generally only have their titles, issue dates and registration numbers available in the public EPO database.

Fashist - 23-12-2007 at 02:03

Really No Idea?
May This System Work?
I have Problem With U Tube For "Acetone Return" in the Vogel Book.
I Change the Design and I Want to Ask May This Sytem Work Well?
Is Good Idea?
Thanks

not_important - 23-12-2007 at 07:57

It's a clever idea, but it has a major flaw -

remember that at the most you'll only convert about 20% of the acetone per pass through the hot tube. You can increase the amount of acetone decomposed to higher percentages, but then increasing amounts of the ketene formed decompose - mostly to carbon monoxide and ethylene but also to small amounts of other stuff that will contaminate the acetic anhydride formed later. In general the experimenters that got the highest overall yields had relatively small conversions per pass, maybe 10%, and recycled the unconverted acetone.

In your latest idea at least 3/4 of the acetone boiled off is going to be condensing in the upper section. It then runs back towards the hot tube section, at first boiling before it reaches it through its cooling of the reaction gases. But there will be an increasing amount of acetone up there, running down and cooling down the upper section of the hot tube. Remember that the acetone doesn't start decomposing until it reaches 500 C or so, so much of the refluxing acetone is just going to be gargling away in the region between the hot tube and condenser, until there's so much that it overwhelms the heated section.

What is your intended production rate per day?

Fashist - 23-12-2007 at 09:19

Mr not important thanks.
You Say Complete True.acetone will not convert to ketene.
But you should accept that in the vogel book(ketene lamp) this is difficult to build U tube for acetone recycle.because the DEPTH of U tube is DEPENDENT to pressure of acetone(boiling rate and amount),This is problem.
i am building one horizontal system.(one 10 lit flask,1m copper tube,1 meter copper condenser,..) i want to run it and write the diffirent result(i will test it with aniline)
but i believe the horizontal isnt good system(we must use 10 lit acetone for have 1lit anhydrid or less)i think the vertical system hasnt this problem but vertical system has U tube problem.what is your suggestion?
for operate my system i want first boil acetone for 5 minutes then i will start the heater because i want no air contain in my tube.i dont want explosion(is good suggestion?)
do you know the u tube calculate?(i think that need gas pressure physic knowledge)
mr not important,thanks

Fashist - 25-12-2007 at 11:40

No Answer?
What is Your Idea About Using Small Piece of Copper, Inside Copper Tube In Heater?(More Surface)
I am Waiting...

not_important - 29-12-2007 at 04:36

If you don't have an acetone return, then you must run the system until you've boiled most of the acetone off, cool it down, add back the condensed acetone plus makeup, bring the boiler up to heat, bring the furnace up to heat, and then start processing the ketene stream. This adds to the amount of time it takes to make a given amount of product.

I've repeatedly suggested you use an absorption tower as in the PDFs. When run as done in the project PDF, the exist gases from the top of the tower are acetone vapour and acetone/ketene decomposition products - methane, ethylene, carbon monoxide.

With a return path for the acetone you could get away with a 2 liter boiler, continuously add makeup acetone to the return stream, and still make as much or more ketene per day as with the open ended large boiler.

Yes, a passive return system will take enough height for the weight of acetone in it to counter the pressure difference between the boiler and condenser. That's the laws of nature, not easy to get around them. Condensing the acetone gives the liquid acetone for recycling at some height above the base of the tower, and likely above the boiler. With that arrangement it's fairly simple to design the system so the acetone return functions properly.

Fashist - 17-1-2008 at 13:07

there is cheaper SUBSTANCE for testing ketene?
aniline is very expensive here.

Fashist - 17-1-2008 at 22:31

I just Know Below Method That isnt Easy


not_important - 18-1-2008 at 02:10

The classic reduction of nitrobenzene uses iron or tin. See

Cooley's Cyclopædia of Practical Receipts and Collateral Information by Arnold James Cooley

Experimental Organic Chemistry - James F. Norris

http://www.qo.fcen.uba.ar/Cursos/org2/tpl1.pdf

Electrolytic Preparations: Exercises for Use in the Laboratory by Karl Elbs, Robert Salmon Hutton

http://www.sciencemadness.org/talk/viewthread.php?tid=9799

and numerous other references.

Nicodem - 18-1-2008 at 14:29

Quote:
Originally posted by Fashist
there is cheaper SUBSTANCE for testing ketene?
aniline is very expensive here.

Aniline costs about 50 EUR/L. Even if it would be 4 times more expensive where you live and assuming you use 0.5 ml for each measurement, then it would cost you 0.10 EUR per test.
I bet you paid more to the internet provider for the time you spent posting and reading the replies.

Fashist - 19-1-2008 at 03:28

My System is Larger than Normal System and I Need to Use 50cc Aniline Per Test.
My Acetone Boiler is 20lit and My Condenser is 2 meter.
I use of internet for sereval Work!.(not just reading)
I have big forum(persian forum about knowledge) and I am active member in Web Programing site and..


[Edited on 19-1-2008 by Fashist]

Nicodem - 20-1-2008 at 11:26

Quote:
Originally posted by Fashist
My System is Larger than Normal System and I Need to Use 50cc Aniline Per Test.

This does not make any sense at all. How is the size of your ketene producing system connected with the amount of aniline you use to determine the concentration of ketene and/or acetanhydride in the product? Why are you using 50 ml of aniline for the testing?

Fashist - 21-1-2008 at 09:30

Mr Nicodem Soon I will Send Picture of My System.
You Said I Use .5 ml for Testing?

hector2000 - 30-3-2008 at 03:44

I am Wonder How Acetyle chloride React With Steel(318) wheras Pure Nitric Acid Cant.! :o
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