-
H H H H
| | | |
H-C-C-0-H + H-C-C-0-H
| | | |
H H H H
catalysts
------------------->
standard room temp
H H H H
| | | |
H-C-C-C-C-0-H + H-0-H
| | | |
H H H H
This is just a general thought question.
This is not for any course but for curiosity only.
The questions are --
What catalyst would you use?
Would this process continue to lengthen the chain?
Regards,
Bill
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Wouldn't you much more easily form diethyl ether?
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That is the problem
I rather create longer chain alcohols
Regards,
Bill
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Go to the nobel prize memorial site and find Olah's nobel lecture in pdf. Towards the end of the paper (from what I remember) it should give you some hints on the catalyst to utilize. This is actually a bad method to synthesize long change alcohols, there are much better ways. However, Olah's method using superacids, strong electrophile and organometallic reagents to obtain a nonclassical carbocation might work. In the meanwhile...
You can work with an epoxide to continue lengthing the change with a terminal hydroxyl group.
Hope this helps.
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This does not sound like occurring at room temperature
Therefore it is implied that it can not be done at room temperature.
Correct???
If so what reactions can occur at room temperature that would eventually lead to a longer chain compound with only carbon plus hydrogen and / or oxygen. And, what would be the catalyst.
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As mentioned above this would be a favored reaction. What would be the catalyst used at room temperature? This is not the result I am interested, but I am curious.
H H H H
| | | |
H-C-C-0-H + H-0-C-C-H
| | | |
H H H H
catalysts
------------------->
standard room temp
H H H H
| | | |
H-C-C-0-C-C-H + H-0-H
| | | |
H H H H
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Let's go one step back. Some bacteria during fermentation of glucose produces butanol (and acetone) instead of ethanol.
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http://www.imba.missouri.edu/funded/2002_7.htm
Has a discussion on fermentation to butanol
Can anyone answer either of the catalyst questions?
Keeping in mind room temperature environment
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I would consider it a great kindness for someone to post the catalyst in the second equation I posted. Maybe several different ones would be nice --
Remember the room temperature constraint
Regards,
Bill
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I doubt if such catalyst exists. You need to break very strong bonds C-H and C-OH.
The weakest bond in ethanol is C-C bond.
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Sorry, I was requesting the catalyst in reply #5 not the catalyst in original post of this thread. Reply #1 said that reply #5 was the preferred reaction. Unless the formula in reply #5 is not diethyl ether. In any case let me restate my last request. What catalyst is needed to convert ethanol into diethyl ether at room temperature? If I got the wrong formula in reply #5 please correct me.
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I dont know any high tech chemistry..
just thinking along this line
ethanol -> ethyl cyanide -> propanoic acid -> propanol -> propyl cyanide -> butanoic acid -> butanol
least this' my 2cents worth
:)
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Thanks for responding -
Would that mean that we put a minute amount of cyanide in a bottle of ethanol we would eventually get longer chain alcohol. I am still also wondering how we get ether from alcohol.
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To get an ether simply perform the williamson ether sythesis. Add a suitable base, which deprotonates the alcohol and this nucleophile attacks another alcohol to become a base.
2ROH + base equivalence ---> ROR
An alcohol and cyanide? I'm not sure this will work since it may be the case that cyanide simply removes the alcohol hydrogen to become HCN...very dangerous.
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Thanks for responding -
Would that mean that we put a minute amount of cyanide in a bottle of ethanol we would eventually get longer chain alcohol. I am still also wondering how we get ether from alcohol.
You would need Lithium Aluminium Hydride to reduce the carboxylic acid to its alcohol.
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So this is the answer to the catalyst questions posted here???
-----------------------------------------
Ethanol to Ether
H H H H
| | | |
H-C-C-0-H + H-0-C-C-H
| | | |
H H H H
NaOH
------------------->
standard room temp
H H H H
| | | |
H-C-C-0-C-C-H + H-0-H
| | | |
H H H H
-----------------------------------------
Ethanol to Butanol
H H H H
| | | |
H-C-C-0-H + H-C-C-0-H
| | | |
H H H H
Lithium Aluminium Hydride
------------------->
standard room temp
H H H H
| | | |
H-C-C-C-C-0-H + H-0-H
| | | |
H H H H
-----------------------------------------
Thank you for responding
Regards,
Bill
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I have recently had time to research Lithium Aluminium Hydride and it will not do. It reacts violently with water. As we know the best ethanol to water ratio is 95% unless you do extensive drying techniques. Also I am not sure that Sodium Hydroxide is the correct catalyst for the ether formula as well.
So I again put out my plea for suggestions on the 2 formulas above as far as catalyst – keeping in mind the desire to accomplish the reactions at room temperature.
Regards,
Bill
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It can't be this difficult, give me a day or 2 to come up with a synthetic plan.
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NaBH4 can substitute LiAlH4
FYI, LiAlH4 is used with a dry medium, usually dry ether.
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Try not to use LAH if you can help it. And don't dump it into EtOH or vice versa. I was the witness of a spectacular (and dangerous) accidental fire from that exact combination. There was some lithium compound so it burned a pretty red color, but that stuff is really nasty. It took nearly 2 L of liquid nitrogen to put the fire out.
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A short couple of years ago there was a huge LAH fire around here at the Pfizer research facility in Groton, CT. One of the LAH tanks in storage sprung a leak and the liquid came rushing out of the tank and immediately catching fire. A bunch of people were hurt and the fire could be seen for miles. Thankfully, the pharmaceutical company had the funding and werewithall to prevent the accident from becoming a major hazard.
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NaBH4 sodium borohydrate seems to be a very interesting substance
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Just so people don't get the wrong idea: LAH is a solid at RT, but Jdurg was most likely talking about a solution of it.
Also, NaBH4 is sodium borohydride, not borohydrate. It is a much more easily handled reducing agent, although not as powerful.
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You are thinking about conversion of ethanol to buthanol in one step using only a "catalist"!!! Is it a joke?!! :confused1:
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There is a new and emerging field of chemistry nowadays.I don't know how many people are aware of it.It is radiochemistry.This is not to be confused with radioactivity or radioactive tracer compounds.But instead entails the use of radio waves as a catalyst to stimmulate chemical reactions.As far-fetched and whacky as this idea might seem,it would be interesting to see if a certain particular frequency of microwave radiation could coax ethanol molecules together to form butanol.It might be a more energy efficient process if it could do this at lower temperatures.There are over 10 million different frequencies to choose from.And different substances are sensitive to various different frequencies.
For example:Inventor John Kanzius has experimented with the idea that radio waves can kill cancer cells.But he accidentally discovered that just the right frequency can break apart water molecules into hydrogen and oxygen.
There are many more examples:coal can be converted to liquid hydrocarbons.It may be more efficient than Fisher-Tropsh method.A radio transmitter can be placed down an old depleted oil well.It can breakdown long hydrocarbon chains of tar into shorter hydrocarbons that can be pumped out.Old discarded rubber tires can be converted to renewable diesel fuel.Just dial in the right frequency for the right material and only who knows what might happen?
Furthermore,in addition to over 10 million frequencies to play with,different combinations of frequencies may be possible.Or radio waves may be used in conjunction with physical material catalysts.Even more combinations of possibilities may be possible if high frequncy ultrasound is added to this growing arsenal of potential catalysts.All of these could be utilized individually or in combination.
What I find interesting about all this is that the stimmulated agitation of molecules by employing radio and/or sound waves (and possibly in conjunction with physical catalysts as well) may be more energy efficient than utilization of thermal energy for chemical reactions.This may make possible all kinds of chemical changes at lower temperatures.....including perhaps a more efficient conversion of ethanol to butanol? Or maybe my whacky suggestions are just nuts.What do you people out there think? I'd very much like some feedback on these ideas.
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What do you people out there think?
Briefly, your text blub contains one reference. An admittedly cursory review of the literature {wikipedia} (http://en.wikipedia.org/wiki/John_Kanzius) shows John Kanzius to be a not particularly reliable source. I'm afraid that puts most of your text into the highly suspect arena. My very basic knowledge of electromagnetism tells me that radio waves have very little energy to impart, by definition, so their effects on matter a very weak. But I'd be interested in perusing some sort of peer reviewed journal on the subject, the Nature article referenced in the wikipedia article for example, as well as the nanogold targeted cancer therapy.
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Once again,on the subject of ethanol conversion to a more desirable fuel,I find it interesting to recall the fact that certain types of zeolite catalysts have been in existence for a long time now that can convert methane and methanol to gasoline.In the process, they split-off water molecules from the H and OH ends of the methanol.
I wonder if these zeolites or somethig similar can convert ethanol alcohol instead of methanol alcohol into gasoline and/or butanol.Because ethanol is a slightly larger molecule than methanol,it may not fit into a methanol active site of the zeolite and require a different type of zeolite or other catalyst when ethanol is substituted for methanol.
Furthermore,these zeolite catalysts only operate at high temperatures,which means high energy cosumption and diminished returns as far as energy invested in the process.
Which brings me back to the interesting idea that I already posted on this website earlier:the stimmulated agitation of molecules by radio and/or sound energy substituted in place of thermal energy to speed-up chemical reactions.
I wonder if there may be certain microwave and/or ultrasonic frequencies that may coax zeolites and other catalysts to perform at lower temperatures.Anything to make a process more energy efficient and less costly (Less alcoholic drinking for myself vs.more alcoholic drinking for my car's engine...Heh,heh,heh).
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I would like to respond to the closed-minded claim by ARKON that most of what I said is in doubt or suspect.Microwave energy sure imparts a lot of heat to water in a microwave oven.And I'm not asking ARKON or anybody else to take my word for anything.There are other examples,like I stated before,of things that other inventors have accomplished...such as breaking down molecules of rubber in old used tires into renewable diesel fuel with microwaves.The inventor who did this was somebody else instead of Kanzius (can't remember the name right off-hand...maybe it will come to me later).And when it comes to energy intensiveness for getting things done,high frequncy ultrasound is no wimp either.It sure has a lot of ummph to it when focused onto kidney gallstones and even it's ability to blast through solid rock (some have even suggested improvising the use of ultrasound for unconventional oil and gas drilling).I still think that radio and/or sound,when used individually or in combination,could help initiate many chemical reactions that may not normally occur on their own.Research other people's claims yourself.Such inventions and chemical conversion methods are starting to gain the attention of others in the science,physics,and business community.
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I would like to respond to the closed-minded claim by ARKON that most of what I said is in doubt or suspect.
You better reread his post. He doesn't claim you are wrong, he states that he will be interested in seeing some peer reviewed publications on the subject. That's not the same thing.
Microwave energy sure imparts a lot of heat to water in a microwave oven.
Single microwave usually doesn't carry enough energy to start any chemical reaction. You need something much closer to visible light for that. E=hν. In microwave owen you use a lot of microwaves, so you transfer a lot of energy on the whole - but in very small portions. Your other example - breaking rubber into diesel fuel - is IMHO an example of thermocracking and microwaves are used as a convenient way of transferring energy, they don't play any crucial role in the chemistry of the process.
I agree with Arkcon - my chemistry knowledge makes me doubt radio frequencies can be used for chemical reaction initiation. It doesn't mean they can't work in some interesting circumstances and I will be happy to learn about such achievements from a reliable source.
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When I originally posted this item my thoughts were more mundane. During fermentation the sugars are not always used up. As the ethanol produced increases it eventually kills off the yeast. I thought that if the ethanol was removed as it was produced that all of the sugar would be consumed. Since I read somewhere that butanol was less soluble in water than ethanol. I thought I would tinker with the process as a citizen scientist. I was not necessarily hoping for an extensive polymerization into longer chain process. Due to the long time since I did any organic chemistry I polled the list to get some ideas. To accomplish the task and have the both processes coexist certain limits had to be put on the environment. The optimum would be that the yeast changes the sugar to yeast and the carbon dioxide and ethanol turned into butanol rise to the top. So the process had to happen in a typical room. High temperatures would kill the yeast. So I requested a catalyst that might lower the activation energy needed to convert ethanol to butanol. It appears that it is not something handy in the textbooks.
Since the post, I have learned that they are now working on direct butanol fermentation (or the like). Also the odor to ethanol is not as repugnant to humans as butanol.
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I give up.There seems to be absolutely no catalytic method whatsoever for chemical combination of two ethanols into butanol at room temperature.Especially not in a simple,single transition step.I have contemplated every possible (impossible?) exotic,unconventional,far-out twilight zone catalytic method known to science.Is there something simple right under my nose?
I have even entertained the idea of cold temperatures below room temperature.This sounds about as counterintuitive as other ideas I've toyed around with.The reaction would proceed at a slow rate,if it even happened at all.If it actually produced butanol in small trace amounts,it would be for pure academic laboratory curiosity rather than practical production in commercial quantities.
According to one theory,Organic precursor molecules of life formed in ice instead of at higher temperatures like always previously believed.
Could try some sort of insane,whacky combination of unconventional ideas:like freezing ethanol molecules in ice and zapping them with a certain frequency of radio (probably just wind-up with melted booze...Heh,heh,heh.LOL. :)
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Thanks for contemplating this process.
On thing, the goal is to be not using energy to create the compound. Also, we don’t want to change the environment so much that it affects the yeast.
The process the yeast uses is done at room temperature and probably uses energy within the sugar to with its enzyme to produce the ethanol.
I am now leaning to break up the ethanol rather than combining. Maybe ethane or ethane is the way to go.
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Here recently,I have been surfing the web to see what is all out there. I was amazed to see how many other people think along the same intuitive lines that I do. Not just thinking about things,but already doing it. I'm also amazed at how many people,even collge educated professors,are ill informed,closed-minded,and simply not "up-to-date" on all the newest technology and inventions out there. I found an endless amount of information about microwave catalyzed reactions. Some about cold-cracking long hydrocarbon chains into shorter ones with almost no heat transfer or pyrolysis involved at all. This involves a combination of very high frequencies much higher than a conventional kitchen microwave. This involves use of klystron tube emitters as opposed to using a magnetron tube as the emission source.
There are other websites that describe my ideas about physical catalysts assisted by radio waves and/or ultrasound. One site describes building up larger molecules out of methane by using a zeolite zsm-5 catalyst in the presence of microwaves. Normally,these zeolites work only at very high temperatures. But the microwave assisted zsm-5 works at room temperature which implies greater energy efficiency.
Of course,this requires an external energy input to drive the microwave transmitter. Furthermore,microwaves and/or ultrasound would probably kill the yeast. The ethanol would probably have to be first separated to a second processing step before dimerization of ethanol to butanol by a microwave assisted catalyst could take place.
I still think it would be nice if there's a miracle molecule out there that alone by itself could pull-off the trick. Butanol is a more desirable fuel,but like you say,it has a less desirable odor.
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This involves a combination of very high frequencies much higher than a conventional kitchen microwave.
Which moves us from the low energy radiation to high energy radiation - or from the realm of fairy tales to the realm of chemistry.
All that you quote is about delivering right amount of energy into right place. The less energy is used to heat up things that don't need to be heated, the better - but the chemistry is still the same. Or at least there is no need for new phenomena to explain what is happening. That is just Occam's razor at work.
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Single microwave usually doesn't carry enough energy to start any chemical reaction. You need something much closer to visible light for that. E=hν. In microwave owen you use a lot of microwaves, so you transfer a lot of energy on the whole - but in very small portions.
If the microwave frequency wasn't strong enough in the first place it would do nothing correct? I was under the assumption that adding quantity does nothing if the initial energy requirement is not met. Photoelectric effect I believe.
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If the microwave frequency wasn't strong enough in the first place it would do nothing correct?
Almost.
I was under the assumption that adding quantity does nothing if the initial energy requirement is not met. Photoelectric effect I believe.
Molecules do move, vibrate, rotate and can have their electrons excited (ie moved to othe molecular orbitals). Each of these has its own energy range - motion and rotation is somewhere at the far IR/microwaves, vibration at IR frequencies, electron excitation in the visible/ultravioler range. Microwaves can either speed up molecule (no spectrum here) or make it rotate faster (that's rotational spectroscopy). Photoelctric effect is about knocking electron out of the atom/molecule, so it is not exactly the same situation. But you are partially right - for example if the wave energy is too low it will be not able to make molecule rotate faster.
That's all oversimplified, but I don't feel like going into details. Not my area.
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There are three possibilities that can happen when a target material is exposed to microwave radiation:
#1.Thermal transfer without chemical reactions: ....This is what happens with water in a conventional kitchen microwave at a frequency of 2.45 Ghz.,using a magnetron tube.
#2.Thermal transfer with chemical reactions: ....This is almost like merely replacing a laboratory bunsen burner with another alternative heat delivery system.
#3.Chemical reactions with almost no heat transfer: ....This third possibility is the one that intrigues me the most.This is usually done with klystron tubes that generate higher frequencies than a magnetron.I can't find the website anymore,but there's a website that describes work by Chinese researchers who made an ethanol to butanol catalyst (normally high temp. catalyst) work at room temperature by assistance from microwaves.I don't know what frequency in hertz it must have been.
BORAK may be correct for the most part in that these frequencies are highly specific.Instead of shaking-up and vibrating an entire molecule of zeolite or whatever else is employed,causing an enormous amount of waste,certain frequencies may specifically target only certain active reaction sites on the catalyst molecule (Perhaps William of Occam can let me borrow some of his Razor blades.This is perhaps the simplest scientific explanation of how I can get a closer shave.....Heh,heh,heh. :)
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have you thought about inorganic catalysts, such as metal / ligand complexes?
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I think perhaps the only way to synthesize butanol in large commercial quantities so as to be real cheap would be to genetically engineer yeast to make butanol instead of ethanol in the first place.Some type of butyric acid pathway I think.This would require insertion of gene(s) with the right DNA sequences.I think researchers are already taking this approach with yeast and E.coli bacteria.The organisms also have to be genetically resistant to butanol because toxicity will kill them at high concentrations.
Also,there are several inorganic,crystalline and metallic catalysts out there that can dimerise ethanol into butanol by splitting-off the hydrogens and hydroxyl groups on the ends and making water molecules.But most of these work only at high temperatures and/or pressures.The MgO catalyst will work at a temp. of 470 K,and 1 bar,while producing lots of other additional byproducts like acetaldehyde and crotonaldehyde.I'm still intrigued by the possibility of some type of microwave assisted catalyst that can drop the temperature and pressure substantially.Perhaps the right combination of frequencies could fine tune it so that less unwanted byproducts are produced (Want to subtract Scooby Snacks for proposing heretical ideas?Go ahead.I'm on a diet.The fictitious cartoon character probably needs them more than I.LOLOL. :) :))
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I think the butanol making bacteria are already being studied. My impression was that normal breading selection processes, not genetic engineering, selected the bacterium. From my memory on reading about this is that butanol is more stinky than ethanol.
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Clostridium fermentation producing butanol is first reported by Pasteur some 150 years ago
http://www.butanol.com/
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I read someone...didn't pay enough attention as I scrolled through this discussion...said that radio waves don't or can't have an effect in chemistry. Plasmas are produced with radio waves. THese plasmas certainly make multitudes of chemistry occur. I'm probably out of context as it is late...but ignoring plasma chemistry produced with radio waves, used extensively in the production of semi-conductors, should be reconsidered. Maybe it wasnt...I don't know, I need sleep. Cheers.
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I read someone...didn't pay enough attention as I scrolled through this discussion...said that radio waves don't or can't have an effect in chemistry. Plasmas are produced with radio waves. THese plasmas certainly make multitudes of chemistry occur. I'm probably out of context as it is late...but ignoring plasma chemistry produced with radio waves, used extensively in the production of semi-conductors, should be reconsidered. Maybe it wasnt...I don't know, I need sleep. Cheers.
I think you have missed the point, it happens when skimming. Please read my message:
http://www.chemicalforums.com/index.php?topic=346.msg89643#msg89643
Radio waves are used to heat up the gas to produce plasma, they are not directly involved in chemistry.
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I finally read through it and I was certainly, actually completely, out of context. Sorry for muddying stirred waters.
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I would like to correct an error I made peviously about the modified MgO catalyst that can dimerise methanol.I misquoted the wrong temperature in which it is operational.It is not 470 degrees Kelvin,but instead is 450 degrees Celsius (wonder what 450 C translates into on the Kelvin scale.I forget).But this is still way above room temperature regardless.I'm still curious if sonication(utilizing high frequency ultrasound) and/or high freq.microwave could possibly reduce the operational temperature of this or other catalysts.Even if not reduced all the way down to room temperature,I still wonder if there is a way to get it lower than 450 C for the modified MgO catalyst or others.I'm also still trying to locate the website about the catalyst Chinese researchers were working on.And I'm also still looking into other possible methods of catalysis for butanol that may be unique or novel.
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wonder what 450 C translates into on the Kelvin scale
450 + 273 = 723
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Here's something of some interest:The Japanese toothpaste manufacturer Sangi Co.has developed a way to synthesize biogasoline,butanol and butadiene from ethanol using the toothpaste ingredient hydroxyapatite as a catalyst.But once again,this is at high temperatures...not at anywhere near room temperature.
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What I find interesting about hydroxyapatite is that it's a naturally occuring chemical compound of calcium found in your bones and teeth.I wonder whether or not the right frequency(s) of ultrasound and/or HF microwave could reduce the working temperature of hydroxyapatite any.Probably not by much.And it would probably still be too slow and inefficient at lower temperatures,as well as lots of other unwanted byproducts besides butanol.
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You will need the same amount of energy to convert. I suppose using room temperature with a catalyst will take a longer time. Now just finding the catalyst is the problem. One thought I was thinking about is having another organism convert the ethanol to another larger chain alcohol since chemistry seems against us.
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I don't think that this reaction would occur under any condition because if yes the other H s would undergo a condensation leading to 2,2-diEthylButane-1-ol.
Lutesium...
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billnotgatez,I think you're absolutely correct.After taking an open-minded look at all kinds of catalysis(including some exotic,far-out methods like ultrasound and/or microwave assisted catalysts),the direct dimmerization of ethanol into butanol with water molecule dehydration removal at room temperature in one simple,beautiful and glorious step just does not seem very amenable to chemistry as we know it.The rules are simply working against us.
Although the beautiful idea is so irresistably tempting you hate to give-up.It's almost like trying 20 billion times to invent a perpetual motion contraption that defies conservation of energy.
Some type of genetically modified yeast or bacteria(which they are currently working on through a butyric acid pathway)is about the best that can be achieved at present time.Mother Nature and living cells already have several billion years worth of more chemical experience in this regard than us humans do.
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There are catalytic routes to produce butanol directly from ethanol. It is a feasible process.
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@mike2011
Can you name one
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Still promising only
http://www.google.pl/url?sa=t&rct=j&q=&esrc=s&source=web&cd=14&cts=1331623278350&ved=0CEwQFjADOAo&url=http%3A%2F%2Fwww.mdpi.com%2F2073-4344%2F2%2F1%2F68%2Fpdf&ei=wPReT8nRLsjV4QSE6LXXBw&usg=AFQjCNEhSdsjhsP00-y7vhrU33kQeMclNQ&sig2=WlXkUzYUcFxy8fIiauAu5Q
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Awesome AWK
Alumina I had heard of before but this confirms
Thanks tons