Sciencemadness Discussion Board

Synthesis of Hexane from Cellulose/Glucose

Detonationology - 24-9-2015 at 07:42

I been looking to order some hexane to use as a solvent for some time now, when I began to question the possibility of synthesizing it from cellulose/glucose. I found some good articles, such as a report on Iridium-Catalyzed Hydrosilylative Reduction of Glucose to Hexane(s) and another regarding Catalyst Pair Converts Cellulose Directly To Hexane, but I was curious if a strong reducing agent such as LiAlH4 would work? Does anybody know of any other novel synthesis' of Hexane?

MrHomeScientist - 24-9-2015 at 08:03

That would be pretty interesting to convert cellulose to something more useful so easily. That catalyst would be difficult to obtain I'm sure. Also the second link mentions an intermediate reaction between glucose and the hydrogen atmosphere. But if the product floats on top of the water layer, wouldn't that block access to the hydrogen?

Amos - 24-9-2015 at 08:45

Quote: Originally posted by MrHomeScientist  
That would be pretty interesting to convert cellulose to something more useful so easily. That catalyst would be difficult to obtain I'm sure. Also the second link mentions an intermediate reaction between glucose and the hydrogen atmosphere. But if the product floats on top of the water layer, wouldn't that block access to the hydrogen?


Stir/aerate?

battoussai114 - 24-9-2015 at 14:30

I'm pretty sure this would be done in a slurry bubble column reactor so you have a nice interface between the liquid, gas and the catalyst. And in such reactor the products floating is not a problem as the hydrogen enters the bottom of the column while the heterogeneous catalyst is suspended in the liquid.

[Edited on 24-9-2015 by battoussai114]

aga - 24-9-2015 at 14:39

Can somebody do an experiment please ?

Preferreably more than 1 somebody.

Edit:

At least define the experiment so some chem bitch whore like me can do it for you.

[Edited on 24-9-2015 by aga]

It frustrates me that there is so much Brain on this forum and so little Doing.

It's just amazingly Strange (to me).

You know how, want to, and do not Do.

[Edited on 24-9-2015 by aga]

fusso - 22-5-2018 at 17:41

I was thinking about oxidizing all OHs to C=O 1st, then reduce to alkane by Zn/H+, but will dichromate break C-C bonds?

[Edited on 23/05/18 by fusso]

Dr.Bob - 22-5-2018 at 17:59

I worked in biofuels for a short time. This (conversion of cellulose to anything useful) type of work is 1) industrial type chemistry, 2) not cost effective, and 3) requires high temps and pressures that are not practical at home. I'm not trying to rain on anyone's parade, making biodiesel with MeOH/NaOMe is a doable task at home, although currently very cost effective, but quite doable. So is making ethanol for fuel (with the permits to avoid being arrested by the feds).

But most other processes require insanely impractical equipment. I have seen some of the chemistry, most loses money in a big way. Most of the pilot plants built so far have closed due to poor yields, poisoned catalysts, and lost money. Maybe one day they will come up with better solutions, or more likely we will learn to bio-engineer plants to produce more useful chemicals directly. That is the direction that I see happening.

If you want hydrocarbon solvents, I would find a good OTC source, like gasoline, white gas, kerosene, starter fluid, etc, and fractionate it. I work in a real lab by day, and even we can't afford iridium catalysts for most reactions.

Sulaiman - 22-5-2018 at 18:14

A friend of mine recently (a few years ago) researched lignin degrading microbial enzymes,
I think that most of her work involved replication of procedures,
and there seems to be lots of literature,
but as there is not a new .com explosion I guess it isn't commercially viable yet.
And there are cellulases, so some kind of fermentation may be viable

[Edited on 23-5-2018 by Sulaiman]

Melgar - 1-6-2018 at 20:34

If you want hexane, I'd recommend distilling it from gasoline before I'd recommend whatever crazy route it looks like you're thinking of trying.

Really though, your best bet might be to go to a few hardware and auto parts stores, then look at the aerosol cans that they have for removing grease or cleaning electronics or brakes or whatever. Hexane is common in those. Then release most of the can's pressure by spraying it while holding it upside down. Then turn it right side up and it will trickle out instead of spray out, and it'll be easier to collect. If the pressure ends up going to zero entirely, so no more is coming out, check and see if you can squeeze the can a little with your hand, indicating pressure is low. Cans can be punctured to let out the remaining contents, but needless to say, this can potentially be very dangerous.

Attempting to use LiAlH4 to make hexane is... what's the best term to use? How about just "no". Just remove that thought from your head. No need to say why, there are too many reasons.

Alternately, heptane is virtually identical in its solvating properties and the only major difference is a somewhat higher boiling point. And heptane is what's left over when you distill the diethyl ether (very valuable solvent) out of starting fluid. Starting fluid is perhaps 70-80% n-heptane, and I've started using it a lot more in recent years just due to the fact that it comes as a byproduct of obtaining ether.

zed - 2-6-2018 at 14:15

Ummm. A few years back, the sharpies, were out, trying to sell pilot plants, to produce fuels based on Levulinic acid Esters. Made from cellulose. But, a quick survey, showed that such esters, were currently either very expensive or unavailable.

If it's so great, why isn't anyone selling the stuff?

It just wasn't a financially viable approach.

Excepting the part, where you send in a big check, as a retainer, for them friendly, slick talking strangers, to start the design work.

The designing and building parts, are practical money makers for the designers. That is where the practicality ends.



VSEPR_VOID - 2-6-2018 at 19:00

Quote: Originally posted by Melgar  
If you want hexane, I'd recommend distilling it from gasoline before I'd recommend whatever crazy route it looks like you're thinking of trying.


Alternately, heptane is virtually identical in its solvating properties and the only major difference is a somewhat higher boiling point. And heptane is what's left over when you distill the diethyl ether (very valuable solvent) out of starting fluid. Starting fluid is perhaps 70-80% n-heptane, and I've started using it a lot more in recent years just due to the fact that it comes as a byproduct of obtaining ether.


I believe that Explosions&Fire on YoutTube made a video on that and had some success.

CaptainPike - 2-6-2018 at 19:14

Fractionate some naphtha? This I have done, if you live in the US you can get it at any hardware store. If you're lucky, you might find Sunnyside Light naphtha, it has more lower boiling point hydrocarbons.

Bert - 2-6-2018 at 22:48

I have a gallon can of "Bestine Rubber Cement Reducer". It is a technical grade of n-heptane.

Look at the SDS for Colman camping fuel sold by the gallon at Wal-Mart, etc. It is mostly cyclohexane.

unionised - 3-6-2018 at 01:19

The idea of reducing glucose to hexane is interesting, but it seems unlikely to be practical.
If I want a fairly volatile, alkane solvent I use cigarette lighter fuel (Zippo fuel).

to aga

JBSC - 17-6-2018 at 19:48

to aga: if you want to see experiments then go to my channel on youtube or BITchute. I do stuff. I do not just talk about it. But i am learning :D

subskune - 25-6-2018 at 02:34

glucose can be converted to sorbitol (hexanehexol) quite easily, maybe a process similar to here:
http://www.sgc.se/ckfinder/userfiles/files/SGC198.pdf
can be created to convert the hexanhexol to hexane (similar to the conversion of the glycerol to propane in the article).

aga - 25-6-2018 at 05:49

Quote: Originally posted by JBSC  
... if you want to see experiments then go to my channel on youtube...

Cheers. I found it, but religion really isn't my thing.
https://www.youtube.com/watch?v=TY6u0Krdphg

[Edited on 25-6-2018 by aga]

roXefeller - 25-6-2018 at 08:31

Quote: Originally posted by Bert  
I have a gallon can of "Bestine Rubber Cement Reducer". It is a technical grade of n-heptane.

Look at the SDS for Colman camping fuel sold by the gallon at Wal-Mart, etc. It is mostly cyclohexane.



When I look it up it seems that cyclohexane might be one of the lesser components. Given the reported boiling point, it seems to be mostly n-heptane.

Attachment: ColemanSDS.pdf (221kB)
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unionised - 25-6-2018 at 10:24

Quote: Originally posted by roXefeller  
Quote: Originally posted by Bert  
I have a gallon can of "Bestine Rubber Cement Reducer". It is a technical grade of n-heptane.

Look at the SDS for Colman camping fuel sold by the gallon at Wal-Mart, etc. It is mostly cyclohexane.



When I look it up it seems that cyclohexane might be one of the lesser components. Given the reported boiling point, it seems to be mostly n-heptane.


Easy to check; put it in the fridge.

BaFuxa - 4-7-2018 at 08:52

This winter I needed hexane to extract some extractives from some wood, I obsessed over hexane ( the n-hexane is quite expensive to buy actually) and in the end I just distilled the hexane isomers 50-68°C from gasoline and they did the job, it is just one non-polar molecule amongst many.