Sciencemadness Discussion Board - question about ethanol synthesis

question about ethanol synthesis

sanity gone - 8-11-2004 at 22:22

Not for drinking btw just want some pure ethanol in my stockroom.

CaC2+H2O-->ethyne

C---C + HCL (in excess) -> chloroethane

Chloroethane + NaOH --> ethanol + NaCl

I have to work out the ratios of the reactions, but I was wondering if this was fesiable? Also, I would purify the ethanol by means of distilation.

Saerynide - 9-11-2004 at 02:05

Why not ferment sugar? I wouldnt want to drink something that once had HCl and NaOH mixed into it

You also might risk blowing yourself up with the acetylene

Marvin - 9-11-2004 at 03:02

Ethyne has a triple bond, so when you add 1 mol of HCl to 1 mol of ethyne you get 1 mol of chloroethene, not chloroethane. Furthur reaction then produces dichloroethane.

If you want ethanol this route, you need to start from ethene.

You have to decide what you want the ethanol for and how pure it needs to be (mainly from methanol and water).

For sheer ease of production I would also recommend fermentation if it needs to be substantially methanol free.

Ethanol Synthesis

Dilaudid - 9-11-2004 at 10:46

Try using a Pallidium catalyst with a ketone(or diol) to get an alcohol

heksogen - 5-6-2005 at 01:05

Hi there,
I haven't post there for year or more,
Sorry for digging up an old thread, but I've got a question on making synthetic ethanol.
Is it possible in a home - laboratory to synthesise C2H5OH from ethylene and H2O steam ?

C2H4 + H2O --catalyst---> C2H5OH

I've heard about H3PO4 beeing catalyst but it had to be mistake, H3PO4 helps to destroy ethanol to ethene.
It should be an electrophilic catalyst...
Has anyone any info on this ????
I think that the reaction is quite interesting, maybe administrators would make a new thread and stick my post to it

...

And finally what about making ethylene from plastic parts, bootles, and others stuff made of PE (poliethylene) or LDPE/HDPE

???

[Edited on 5-6-2005 by heksogen]

[Edited on 5-6-2005 by heksogen]

unionised - 7-6-2005 at 12:47

Any catalyst that works for a reaction in one direction will also work for the reverse reaction. H3PO4 would work, but it's easier to make beer and distill it.

Distill

MadHatter - 7-6-2005 at 13:34

Unionised, I couldn't agree more with your last post. Distillation works great ! Why bother
with any synthetic methods when Nature's little chemists will do it for you !

heksogen - 8-6-2005 at 06:00

LOL, I don't want to drink this

I just think of making technical grade alkohol
My neighbour runs an environment firm which take taxes from firms which pollute the air or water with toxic or harmfull materials. Now he also take different kinds of plastics - he take money for waste disposal, nowadays he take 10tons of poliethylene a month but he can take even several times more. He earns 15groszy (5 american cents or 4euro-cents) for every kilogram of PE and he doesn't know what to do with theese plastics - they just lie in magazine. I talked with him and suggested starting making ethanol - firstly test it in lab-scale, then run little production, end if that would give money , build a factory

I don't know if my idea is good but it sounds nice... I've heard about factory making ethanol from ethylene from petroleum and using ethanol as an additive to petrol...

docberto - 8-6-2005 at 19:57

I don't think polyethylene can be depolymerized to ethylene.

a123x - 8-6-2005 at 21:30

An idea I had for making rather pure ethanol was to simply take ethyl acetate and react it with NaOH. This will give sodium acetate and pretty much anhydrous ethanol if you start with anhydrous ethyl acetate.

Oh, and the distill the ethanol from the sodium acetate. This should be pretty obvious but I'm editting my post to put it in anyway.

[Edited on 9-6-2005 by a123x]

sparkgap - 8-6-2005 at 21:51

docberto: yes it can, steam can do it, see Rosco and neutrino's posts here, near the end of the thread.

sparky (~_~)

[Edited on 9-6-2005 by sparkgap]

unionised - 9-6-2005 at 10:33

"An idea I had for making rather pure ethanol was to simply take ethyl acetate and react it with NaOH. This will give sodium acetate and pretty much anhydrous ethanol if you start with anhydrous ethyl acetate"

Oh no it won't. You will get the Claisen condensation of the ester.
If you adfd lots of water you will get alcohol and you can clean that up by distilation.

hAzzBEEn - 26-7-2005 at 11:47

Polyethylene doesn't depolymerize. Quote from Praktikum Polymer Science/Polymerisationstechnik: Thermal degradation of polymers (SS 2002)

Quote:

Polymers that don´t depolymerize, like polyethylene, generally decompose by thermal stress...

If one want's lab grade 99% ethanol: fermentation, distillation to 96%, and molecular sieve for >99%.

neutrino - 26-7-2005 at 13:53

Digging around a little, I found that it actually does—but not how we thought. From the Wikipedia, we have this:

Quote:

Polyethylene usually degrades by random scission - that is by a random breakage of the linkages (bonds) that hold the atoms of the polymer together. When this polymer is heated above 450 Celsius it becomes a complex mixture of molecules of various sizes which resemble gasoline.

Back to the drawing board, I guess.

Fleaker - 28-7-2005 at 17:37

I'd just ferment. A mixture of 2L molasses, 450g brown sugar, 8L warm water and 5g yeast fermented for 20 days (with a trap to prevent oxygen from getting in) Distill it 3 times. Then go with the sieve or even use sodium wire (empty tomato paste can with a hole punched in bottom works well when making Na wire) to dry. Or you could just go buy a bottle of the cheapest vodka you can find...

neutrino - 28-7-2005 at 19:57

And then there are those of us who know better than to drink strong bases...

Fleaker - 28-7-2005 at 21:52

Quote:

Originally posted by sanity gone
Not for drinking btw just want some pure ethanol in my stockroom.

I don't think he wanted to drink it.

neutrino - 29-7-2005 at 06:26

I was referring to your sodium wire idea.

praseodym - 30-7-2005 at 03:39

question about ethanol synthesis.....

Are you limited to the substances you can use for making ethanol?? Because the process you have stated is a very tedious way of getting ethanol. Why not try other simpler methods such as fermentation or reduction of acetaldehyde or perhaps hydration of ethene??

Nerro - 30-7-2005 at 04:21

On a slightly off topic note,

Stores sell trichloroethene as a degreaser. Do you think that might be converted to tetrachloroethane with HCl? And if that's possible whether or not that could be converted to ethanetetra-ol? I don't think that would be stable so what would that then dehydrate into? ethane-dial? (dunno english nomenclature too well

I mean H(OC)-(CO)H)

Madandcrazy - 30-7-2005 at 07:32

Nifty idea get ethanol from degreasers

.

A easy way would give ethanol from ethylcarbonate.

Ethyl Acetate

FloridaAlchemist - 31-7-2005 at 06:56

If one could get ethanol from ethyl acetate then maybe we could convert the solvent grade denatured ethyl alcohol to ethyl acetate. Then convert that back to ethyl alcohol without most of the denaturants.

sparkgap - 31-7-2005 at 17:41

"If one could get ethanol from ethyl acetate..."

Saponification anyone?

sparky (^_^)

praseodym - 31-7-2005 at 23:09

But i don't understand why do you have to go to such lengths just to get ethanol?? Why can't simpler methods be used instead?? If it is just to get ethanol, i recommend using the easier, more 'conventional' methods. Unless...unless you are limited to certain chemicals given. If it is for fun, then saponification will then be quite a good idea.

sparkgap - 1-8-2005 at 01:44

Exactly what "simpler methods" or "easier, more 'conventional' methods" did you have in mind?

Not everyone has yeast. Also, not everyone has a good source of legal alcohol (denatured and/or otherwise). Maybe it is just for the fun of it. What's wrong with seeking more ways to skin a cat? That's how (mad) science progresses!

The easiest route for one is not necessarily the best for the other. Sometimes the more tortuous route may be more appropriate with his/her given(s). Keep that in mind.

sparky (~_~)

P.S. Oh, just look at that nice row of stars... sweet.

Post # 500!

12AX7 - 1-8-2005 at 02:53

Quote:

Originally posted by sparkgap
Not everyone has yeast.

Bollocks, you're hard pressed to find anywhere on Earth that doesn't have yeast! Just open the window.

If you want a good starter yeast, Google for how to prepare some for breakmaking. I know food.com has at least something. Plus you have yeast individual to your location, so it's more unique than store bought yeast.

Quote:

P.S. Oh, just look at that nice row of stars... sweet.

Post # 500!

Congrats, one of us spammers\\\\big posters now.

Tim

sparkgap - 1-8-2005 at 03:22

I guess I should rephrase that to "not everyone can buy a nice clump of S. cerevisiae in their local shops".

But you're right, there's more than enough yeast to go around on Earth.

sparky (~_~)

P.S. You're newer, but you became an I.H. first. Hmm...

Organikum - 1-8-2005 at 05:54

Quote:

My neighbour runs an environment firm which take taxes from firms which pollute the air or water with toxic or harmfull materials. Now he also take different kinds of plastics - he take money for waste disposal, nowadays he take 10tons of poliethylene a month but he can take even several times more. He earns 15groszy (5 american cents or 4euro-cents) for every kilogram of PE and he doesn't know what to do with theese plastics - they just lie in magazine. I talked with him and suggested starting making ethanol - firstly test it in lab-scale, then run little production, end if that would give money , build a factory

Quote:

I suppose thats the answer, gasoline instead of ethanol.

12AX7 - 1-8-2005 at 08:44

Quote:

Originally posted by Organikum

Quote:

I suppose thats the answer, gasoline instead of ethanol.

Heck, add a catalyst (I forget what?) and get all sorts of useful fuel gasses, solvents, oils and -enes from free milk jugs!

Tim

praseodym - 2-8-2005 at 07:15

Ethylene glycol with dimethylterephthalate to get ethanol as one of the products, anyone??

sparkgap - 2-8-2005 at 09:14

Am I missing something, or have you found a way to turn terephthalate and glycol into ethanol? You wouldn't mind telling us, 'no?

sparky (~_~)

[Edited on 2-8-2005 by sparkgap]

12AX7 - 2-8-2005 at 10:21

PETE is dehydration or transesterification, in the latter case methanol (a mono-ol), or ethanol would work for that matter, is replaced by ethyl-diol.

Which reminds me, I was thinking earlier today, since EtOH can be dehydrated to ethyl ether, couldn't ethylene glycol be dimer/etherized to di-(ethyl-2-ol) ether and/or polymerized further?

Tim

sparkgap - 2-8-2005 at 11:25

Actually, it's oxirane (ethylene oxide, oxacyclopropane) that's used for that purpose. That's where you get diethylene glycol, triethylene glycol, and all those nice grown... err, "crown" ethers.

sparky (~_~)

[Edited on 2-8-2005 by sparkgap]

trilobite - 2-8-2005 at 11:59

You get dioxane from ethylene glycol that way.

Fleaker - 2-8-2005 at 13:39

Probably just easier to distill it or buy cheap liquors, but getting the water out for absolute/anhydrous alchohol is troublesome.

epck - 2-8-2005 at 14:57

Slightly off-topic but...

Has anyone tried obtaining methanol from wood? It is one of the by products from the charcoaling process.

Fleaker - 2-8-2005 at 20:43

Yeah, but you also get other condensates besides methanol. Still, if you have access to a 55 gallon drum, some piping, and a welder one could easily make a retort. Hmm, methanol while charcoaling for a cupola/furnace (or for your BBQ).

12AX7 - 3-8-2005 at 00:04

Should be all sorts of interesting aromatics, tars and whatnot, too. Plus terpenes with sappy pine. Psst, pine charcoal burns good in pyrotechnia

Tim

praseodym - 3-8-2005 at 05:53

Quote:

[quoteYou wouldn't mind telling us, 'no?

sparky (~_~)

Not that i do not want to tell. I myself am not so sure about it.
But this is what i think it will look like:
(CH2OH)2 + C6H4(COOCH3)2 --> ethylene terephthalate + ethanol