Sciencemadness Discussion Board

furfural

Magpie - 11-3-2011 at 15:20

For those of you who love heterocyclic compounds I will describe my experiment in making furfural. I used the procedure in the forum library in Gattermann (1937).

300g of oat bran was used as substrate. This was steeped in dilute sulfuric acid then steam distilled yielding 700mL of distillate. The residue in the pot was char, easily removed. The distillate was neutralized with Na2CO3 then saturated with salt and distilled, collecting 300mL. This distilllate was then salt saturated again and extracted with 50mL of ether. The ether was removed by simple distillation leaving 1-2mL of crude furfural in the pot, not enough to purify. It gave a strong postive Tollen's test (silver mirror) for aldehyde. It has a subtle and pleasant smell of coffee and almond. If I ever do this again I will use the procedure in OrgSyn, hopefully to get a better yield.

Questions and comments are welcomed.

Paddywhacker - 11-3-2011 at 16:49

That's an interesting comparison with the Orgsyn procedure, Magpie.

The process depends on the dehydration of pentoses, so the the higher the pentose concentration in the raw material the better. Starch and cellulose are hexoses, and don't give any furfural.

So the question becomes "what is the best OTC source of pentoses?"
Bran and corncobs have been used in the past, but is there something better?

DJF90 - 11-3-2011 at 17:21

Xylose, if you can get it. Unfortunately its not a common thing here in the UK...

UnintentionalChaos - 12-3-2011 at 06:37

I had a friend make the brilliant suggestion to use ribose, available as a very questionable bodybuilding upplement, as feedstock. It's another aldopentose and I don't see why it wouldn't work. Not as cheap as bran or corn cob and without the old-timey feel you may be going for, but compact volumes and hopefully higher yield.

[Edited on 3-12-11 by UnintentionalChaos]

Magpie - 12-3-2011 at 09:52

Quote: Originally posted by UnintentionalChaos  
I had a friend make the brilliant suggestion to use ribose... It's another aldopentose and I don't see why it wouldn't work.


There are four aldopentoses: arabinose, lyxose, ribose, and xylose. Each has D- and L- configurations.

Are any of these favored in the formation of furfural, aside from availability?

blogfast25 - 15-3-2011 at 14:02

Quote: Originally posted by Magpie  
300g of oat bran was used as substrate. This was steeped in dilute sulfuric acid then steam distilled yielding 700mL of distillate. The residue in the pot was char, easily removed. The distillate was neutralized with Na2CO3 then saturated with salt and distilled, collecting 300mL. This distilllate was then salt saturated again and extracted with 50mL of ether. The ether was removed by simple distillation leaving 1-2mL of crude furfural in the pot, not enough to purify. It gave a strong postive Tollen's test (silver mirror) for aldehyde. It has a subtle and pleasant smell of coffee and almond. If I ever do this again I will use the procedure in OrgSyn, hopefully to get a better yield.



Interesting. What were the steeping conditions? Do you simply leave it to stand for some time?

Ribose may (or may not) yield higher yields of furfural but look at these internet prices! Steep (no pun intended)!


[Edited on 15-3-2011 by blogfast25]

Magpie - 15-3-2011 at 14:29

Quote: Originally posted by blogfast25  


Interesting. What were the steeping conditions? Do you simply leave it to stand for some time?


Actually, I think "steeping" is not really required here and is my misnomer; it was not called for in the procedure. Steam distillation conditions that are used to separate out the mash are probably all that is required to hydrolyze the pentosans. I let the mix of dilute sulfuric and bran sit overnight merely for my convenience.

I've done some pricing of d-ribose and the best I've seen is about $11/100g. So if you wanted a quantity of furfural that seems like the way to go.

I was surprised how reactive it was in the Tollen's test - put benzaldehyde to shame. No heat was required for either, however.


CORNCOBS r cheap

jimwig - 15-3-2011 at 15:37

CORNCOBS r cheap

UnintentionalChaos - 15-3-2011 at 17:56

Quote: Originally posted by jimwig  
CORNCOBS r cheap


Giant bloody flasks and heat sources to hold the volume needed to make comparatively small amounts of furfural with them are not.

[Edited on 3-16-11 by UnintentionalChaos]

blogfast25 - 16-3-2011 at 06:25

Thanks Magpie…

Far more interesting than furfural would be the famous derivatives of THF. I suppose the hydrogenation is outside the capability envelope of most of us here?

The price of Ribose must be somewhat artificially inflated by its primary market. These guys and galls will pay virtually anything!

And how about d-fructose: considerably cheaper than ribose. Wiki:

"DehydrationFructose readily dehydrates to give hydroxymethylfurfural ("HMF"). This process may in the future be part of a low-cost, carbon-neutral system to produce replacements for petrol and diesel from plantations."

Ah... unleaded HMF, super! :)

[Edited on 16-3-2011 by blogfast25]

Magpie - 16-3-2011 at 09:06

It is interesting that the Gattermann procedure says to expect a yield of 6-7g on 300g of oat bran. This is 0.020-0.023g/g. The OrgSyn procedure, however, says to expect 165-200g/1.5kg of corncobs. This is 0.110-0.133g/g. This a 5-fold yield for the corncobs over the oat bran.

ScienceSquirrel - 16-3-2011 at 09:26

Ribose will form furfural on heating with acid;

http://www.cerlabs.com/experiments/10875404464.pdf

If you wanted a few grams of fufural I think this would be the way to go, 25g of ribose reacting in a 50ml flask to yield maybe 10g grams of furfural sounds way more tempting.

Furfural from Corncobs

gsd - 16-3-2011 at 09:46

A set of 4 articles on this subject appeared in I & EC in 1923-24
by Frederick B. LaForge and Gerald H. Main

I—Factors Influencing the Furfural Yield in the Steam-Digestion Process
II—The Bureau of Chemistry Experimental Plant and Process for Furfural Production
III—Effect of Catalysts on Furfural Yield in the Steam Digestion Process
IV—Economic Aspect of Furfural Production

They are attached below.

Besides this I remember there was an excellent article on comparative study of furfural yields from several pentosan sources such as Oat meal, corn cobs, groundnut husk, rice husk, sugarcane baggase etc. in one old issue of J Chem & Met Engg, which unfortunately is not on the net. I have a photocopy somewhere but it will need lot of digging.

gsd




Attachment: Furfural from Corncobs-I.pdf (158kB)
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Attachment: Furfural from Corncobs-II.pdf (581kB)
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UnintentionalChaos - 16-3-2011 at 11:02

Quote: Originally posted by blogfast25  
Thanks Magpie…

Far more interesting than furfural would be the famous derivatives of THF. I suppose the hydrogenation is outside the capability envelope of most of us here?



You never know. Furfural is not a highly aromatic system to the point that strong acid will cleave the ring. It should be much more readily hydrogenated than say, benzene. You probably will not get the aldehyde to a methyl using any easy lab conditions.

IIRC rhodium catalysts can reduce even benzene rings at room temp and 1atm (I may be wrong, don't quote me on it) so they would be great for this.

[Edited on 3-16-11 by UnintentionalChaos]

Magpie - 29-3-2011 at 12:47

For those really into sugar chemistry I see that d-arabinose can be made from calcium gluconate. There is a procedure for this in the forum library that I can't find at the moment. Calcium gluconate is about 1/4 the cost of d-ribose. IIRC arabinose is an aldopentose and should, like ribose, yield furfural upon hydrolysis.

Edit:

Here it is:
http://library.sciencemadness.org/library/books/an_advanced_...

In fact, you can even start with glucose, as the procedures show.

[Edited on 30-3-2011 by Magpie]

[Edited on 30-3-2011 by Magpie]

Magpie - 25-4-2011 at 19:13

Disappointed with the yields of my previous experiments in making furfural, I tried again, this time with fairly good success.

I used a 1/10th scale version of the Org Syn procedure, substituting d-ribose for corn cobs. My pot was a 1000mL RBF with a Hempel column and whatever else I could find to build a long vertical tube. The receiver is a 25mL side-arm test tube. A picture of the assembly is shown below. It uses a Dean Stark mechanism to separate the furfural from the aqueous phase. Density of furfural is 1.159 @13C so it separates nicely from the water. Solubility in water is 9.1g/100, so it is advantageous to use as small a receiver vessel as possible.

I charged the pot with 500mL of 2.17N H2SO4, 200g NaCl, and 32g of food grade d-ribose. This was then set to boiling for 3 hours. As usual the pot contents turned black once boiling temperature was reached. So, all that carbon has to be considered a loss in yield. 8mL, or ~9.3g, of crude furfural was recovered as a translucent yellow liquid. This is a yield of 45.3% based on the d-ribose charged.

Questions, comments, and discussion are welcomed.

furfural system (org syn).jpg - 190kBfurfural 1-liter pot.jpg - 201kBcrude furfural (~8mL).jpg - 164kB

ScienceSquirrel - 26-4-2011 at 04:58

I think you might do a little better if you added some salt to the collection vessel. The solubility of organic chemicals in water is affected by the presence of other disssolved materials.
Also extraction with ether would probably get some more of the furfural out of product.
Was there substantial amounts of black material or was it just colouration?
A little black goo goes a long way! :(

Magpie - 26-4-2011 at 09:47

Quote: Originally posted by ScienceSquirrel  
I think you might do a little better if you added some salt to the collection vessel. The solubility of organic chemicals in water is affected by the presence of other disssolved materials.
Also extraction with ether would probably get some more of the furfural out of product.
Was there substantial amounts of black material or was it just colouration?
A little black goo goes a long way! :(


The small amount of water in the reciver (<20mL) becomes saturated with furfural early in the distillation. From then on the furfural just drops out and settles on the bottom of the test tube. The water in the tube is continually being dribbled back to the pot and refreshed with incoming distillate. I agree that at the end of the distillation I should be able to drive the 8% or so of dissolved furfural out of the water by adding salt.

Yes, ether would be a good solvent but then there is the mess and stink of handling it. On this small scale I don't see it being worth the effort.

As you say, a little black goo goes a long way. I just emptied this flask. Because of the remaining salt it is a little hard to quanitfy the amount of carbon. Several grams is about all I can say.

In August when Mrs Magpie cooks "sweet corn," ie, "corn-on-the-cob," I may give corncobs a try.

GreenD - 26-4-2011 at 12:53

Excuse me, but what is the fuss about furfural?

Are you fellas into biomass and biofuels, or what am I missing here?

ScienceSquirrel - 26-4-2011 at 13:30

I think you are right and there is little more to be gained.
It is a complex condensation reaction and the chance of any one molecule of ribose twisting around to the right conformation, eliminating and condensing in the right reaction order to make furfural or making goo may have a statistical limit.

watson.fawkes - 26-4-2011 at 13:54

Quote: Originally posted by GreenD  
Excuse me, but what is the fuss about furfural?
It's feedstock into furan, and from there to tetrahydrofuran (THF) and others.

Magpie - 26-4-2011 at 14:24

Quote: Originally posted by ScienceSquirrel  
...
It is a complex condensation reaction and the chance of any one molecule of ribose twisting around to the right conformation, eliminating and condensing in the right reaction order to make furfural or making goo may have a statistical limit.


That is an interesting way to look at it. Indeed, each ribose molecule must lose 3 molecules of water to form furfural. I too was wondering why so much of the ribose ends up as carbon. At first I was using a much stronger acid, even sulfuric, which is known for its tendency to carbonize. But this last batch was only 2.17N in H2SO4, or HCl, however you want to look at it. OrgSyn, however claims a very high yield when using corncobs. We'll see how I do with those in August.

@GreenD: I'm making furfural just for the heck of it. It's an interesting looking aldehyde, and being able to make it from corncobs, straw, oat hulls, etc, just adds to the intrigue.

Arthur Dent - 27-4-2011 at 04:03

@ Magpie: Quick question, what do you do to the corn cobs to prepare them into a primordial soup? Just dilute sulfuric acid? How long does it take to boil off? Corn cobs are pretty sturdy things, so I figure it might be a long process to digest those...

- Robert

Magpie - 27-4-2011 at 07:45

Robert, here's the procedure as found in OrgSyn. For those who don't know, this cornocopia (no pun intended) is freely available to the public. ;)

http://www.orgsyn.org/orgsyn/default.asp?formgroup=basenpe_f...

Yes, the cobs apparently can take 5-10 hrs to digest.

blogfast25 - 27-4-2011 at 07:49

A very interesting experiment, Magpie, look forward to the details on the corn-on-the-cob run.

If only there was an easy way to convert to THF. Or is there?

How much did the ribose set you back?

Magpie - 27-4-2011 at 08:12

Quote: Originally posted by blogfast25  

How much did the ribose set you back?


I paid $20/100g at my local health food store. I've seen it on the internet as cheap as $11/100g.

---------------------------------------------------------------------
According to OrgSyn furan can be made easily by the decarboxylation of 2-furoic acid. OrgSyn also shows how to make this acid from furfural. It looks simple enough.

[Edited on 27-4-2011 by Magpie]

blogfast25 - 27-4-2011 at 11:57

Wow. $110/kg. Cheap it ain't!

aliced25 - 2-6-2011 at 19:02

Here's a few papers on the production of furfural from pentoses. They cover producing useful pentoses from the oxidation of hexoses and the formation of furfuryl from pentoses (the biphasic systems look awfully promising).

Attachment: Fullmer.etal.The.Production.of.Furfural.from.Xylose.Solutions.by.Means.of.Hydrochloric.Acid.Sodium.Solutions.pdf (488kB)
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Attachment: Heines.Microdetermination.of.Pentoses.by.the.Bisulphite.Method.pdf (81kB)
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Attachment: Hockett.Hudson.Improvements.in.the.Preparation.of.d.Arabinose.from.Calcium.Gluconate.pdf (246kB)
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Attachment: Hudson.Harding.The.Preparation.of.Xylose.from.Corn.Cobs.pdf (151kB)
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Attachment: Hurd.Isenhour.Pentose.Reactions.I.Furfural.Formation.pdf (881kB)
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Attachment: Isbell.Holt.Frush.Preparation.of.D.Arabinose.5C14.from.D.Glucose.6C14.pdf (61kB)
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Attachment: Matsushima.D.Arabinose.Hypochlorite.Glucosamine.pdf (258kB)
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Attachment: Weingarten.Kinetics.of.Furfural.Productioni.by.Dehydration.of.Xylose.in.a.Biphasic.Reactor.with.MW.Heating.pdf (348kB)
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asilentbob - 8-6-2011 at 22:46

Xylitol is readily available OTC from health stores, grocery stores, etc as a sugar substitute... I have wondered if it could participate similarly to xylose, except losing 4 moles water per mole of xylitol, instead of 3.

Its been entirely too long since I took Ochem.

Magpie - 13-8-2011 at 16:19

I have been drying some corncobs for making furfural per the method in OrgSyn. I'm getting them as they are received from the dinner table. I crushed 4 of them up yielding 114.4g for a 0.076 scale batch.

Dried corn cobs are a bitch to granulate. I eventually settled on using a pair of channel locks but it still took me 2 hours of tough going. The kernel hulls are fragile but the center core is very tough, much like wood. If I ever do this again I will try making them into sawdust using my table saw.

I made up enough H2SO4/NaCl solution for a 0.10 scale batch and since the cob granule slurry looked too dry I added it all. Tomorrow I will set up for steam distillation using a 1000mL RBF, column, and Dean Stark trap, as before.

Here's some pictures:

crushing cobs.JPG - 113kBcob slurry.JPG - 112kB

blogfast25 - 14-8-2011 at 05:26

Someone should contemplate recycling these things into baseball or cricket bats...

Look forward to reading about the rest of this synthesis! :)

Ozone - 14-8-2011 at 09:49

Many seed hulls, particularly those from sunflower seeds, are especially rich in hemicellulose (primarily arabinoxylan with almost no cellulose). I expect these to be excellent feedstock for a process like this. I might give it a shot after I get a kg or two of seed hulls.

Cheers,

O3

Magpie - 14-8-2011 at 20:57

Quote: Originally posted by Ozone  
... sunflower seeds, are especially rich in hemicellulose (primarily arabinoxylan with almost no cellulose). I expect these to be excellent feedstock for a process like this.


If this converts to arabinose it indeed ought to be a good feedstock & interesting to compare to the oat bran, corn cobs, and d-ribose that I have used.

The steam distillation of the corncob hydrolysis was completed today. I ran it for 4 hours but it was pretty much finished after 3 hours. OrgSyn's preparation says it will take 5-10 hours for their 1.5kg batch.

My yield was 7.5g. Scaled on OrgSyn's expected yield I should have obtained ~15.2 g. But my vastly smaller scale (0.076X) is likely a major factor in my smaller yield.

Again the mash turned black after it started boiling. Pictures are shown below.

This completes my investigation of natural products for the preparation of furfural. If I want any more I'll use d-ribose as available from my neighborhood health food store.



corn cob distillation.JPG - 109kB corn cob furfural.JPG - 67kB

[Edited on 15-8-2011 by Magpie]

Magpie - 2-9-2011 at 14:17

Wanting to do some chemistry this week, but nothing too challenging, I decided to purify my crude furfural and then make a derivative of same.

I took the combined lots of furfural that I had made from the various sugar and pentosans, which amounted to about 25mL of straw colored translucent liquid, and vacuum distilled it. Pressure was 50mmHg using an aspirator with the resulting bp at 76C. Being a bit lazy I did not at first set up an ebulliator and a Claisen extension. This proved to be a big mistake due to bumping and carryover so shutdown and reconfigured the right way. Yield was 20mL of clear product with a pleasant aroma - I would call it that of "benzaldehyde light."

Using 1g of homemade semicarbazide, some Na acetate buffer, and 1.5mL of furfural I made the derivative furfural semicarbazone (an imine) according to the method in Brewster. This crystallized out without any help from scratching or cooling. I recrystallized it from 95% ethanol, washing it with same. A melting point was taken of the dried crystals (see picture); it melted at the literature (Wiki) value of 202C.

I find it interesting that furfural is aromatic. Also it is interesting that the terminal nitrogen of the semicarbazide is the only one (of 3) capable of nucleophillic attack due to resonance.

furfural semicarbazone.JPG - 93kB

[Edited on 2-9-2011 by Magpie]

Random - 2-9-2011 at 21:47

Well, I tried dry distillation of sucrose before, until it carbonized. I obtained very small amount of liquid with the color just like this crude furfural you made, though it had some oily caramel colored dot floating on that yellow liquid. The liquid smelled like burning sugar and caramel (and I wonder why :D). My distillation apparatus was made from aluminium foil so it was really bad one, a lot of fumes escaped. Maybe that liquid contained furfural too?

Nicodem - 3-9-2011 at 12:13

Good work Magpie!
Quote: Originally posted by Magpie  
I find it interesting that furfural is aromatic.

Aromatic, but not much. If you think furane is much of an aromatic system, then you might be surprised at how easy it undergoes nucleophilic additions. Particularly the reactions with amines and anilines are interesting as they give the corresponding pyrrole compounds from the furanes. For example, furfural itself reacts with anilines such as p-nitroaniline to give 1-(4-nitrophenyl)-1H-pyrrole-2-carbaldehyde. This is a nice looking heterocyclic product which can be further functionalized at the aldehyde group. References:

See DOI: 10.1071/CH9850953

Also, from CA 92:180923
Quote:
Synthesis of 1-arylpyrrole-2-aldehydes from furfural and substituted aromatic amines.
Burmistrov, S. I.; Sannikova, V. M.
Voprosy Khimii i Khimicheskoi Tekhnologii (1979), 54 20-4.

Abstract: Pyrrolecarboxaldehydes I (R = 4-H2NSO2C6H4, Q, 4-nitro-1-naphthyl, 2,5- and 2,4-HO(O2N)C6H3, 2,3,5-HO(Cl)(O2N)C6H2) were prepd. in 23.2-87.6% yield by reaction of furfural with the resp. arom. amine. The semicarbazones, phenylhydrazones, 4-nitrophenylhydrazones, 2,4-dinitrophenylhydrazones, and azines of some I were also prepd.

...and from CA 95:203666
Quote:
Synthesis of 1-(4-nitrophenyl)pyrrole-2-aldehyde from furfural.
Baum, E.; Goldovskaya, T. E.; Kul'nevich, V. G.; Maiorova, O. V.
Khimiya Geterotsiklicheskikh Soedinenii (1981), (8), 1062-6.

Abstract: The condensation of furfural with p-O2NC6H4NH2 in different solvents (e.g., MeOH, EtOH, PrOH, DMF, or HOAc) contg. HCl gave 55% pyrrolealdehyde I and 27% 2,3-bis[(4-nitrophenyl)amino]-4-cyclopentenone. Yields of up to 70% were obtained using methods described earlier (e.g., Liipke, 1939).

...and briefly described in DOI: 10.1007/BF01042479

aliced25 - 3-9-2011 at 15:16

Bagasse is going to be far easier to work with than corn cobs (given it is already shredded and readily available in most garden stores - it is used as mulch). Rice husk is another easily (and cheaply) acquired source of xylose, there is a paper (here) on the extraction of xylose from Rice Husk/Hulls using 1N H2SO4. Making furfural from the sugar is going to be way easier given the lack of bulk and the reduction in the amount of acid needed.

Magpie - 3-9-2011 at 17:48

I agree that it is good to reduce the bulk of the precursor as much as possible. Although expensive, I did this using OTC d-ribose. However, even using this pure sugar the best yield I could get was 45%. When I tried it again I got exactly the same yield. A great deal of the precursor is just turned to carbon.

Ozone - 4-9-2011 at 07:41

Just some notes on your alternative feedstocks:

Yes, but bagasse contains 50% w/w water and 2-4% residual cane juice; it is only 20-24% hemicellulose (most of which is arabinoxylan). It is also recalcitrant. I would go for cellulosic ethanol then concentrate and work on the stillage (which contains all sorts of interesting things like aconitic acid, your xylan, etc.)

NIST sugarcane bagasse (from my lab % w/w dry solids):

extractables: 4.4
Cellulose: 40.2
Hemicellulose: Xylan 21.8, Arabinan 1.8 and mannan 0.4
Lignin: Klason 22.3, AS 2.0
Ash: 4.0

Rice hulls come nice and dry, which is a plus for storage and compositionally simple. But, again, these are a rich cellulose source with a composition (La. rice hulls, results from my lab) similar to:

extractables: 2.2
Cellulose: 33.0
Hemicellulose: Xylan 15.8, Arabinan 1.3 and mannan 0.0
Lignin: Klason 24.0, AS 2.7
Ash: 19.0

It should be mentioned that rice hulls are flame retardant (I had a hard time getting them to combust in a Parr bomb under 19 atm O2) and that the huge amount of ash is part of the plant structure; it is at least 94 % silica.

Cheers,

O3

[Edited on 4-9-2011 by Ozone]

blogfast25 - 5-9-2011 at 07:38

Very interesting data, O3. Also that point on > 94 % silica in ash, I wonder how that compares to most plant ashes...

Ozone - 5-9-2011 at 20:13

Yes, I thought so, too. When totally combusted to ash, you get a *fine* pure-white silica. I have thought about trying it out (as a stationary phase) in a column.

It would be cool if we could source relatively high-grade silica from rice hulls.

Cheers,

O3

watson.fawkes - 7-9-2011 at 04:00

Quote: Originally posted by Ozone  
It would be cool if we could source relatively high-grade silica from rice hulls.
Certain species of horsetail are known as "scouring rushes" because of the high content of silicates; they're a naturally occurring plant abrasive. I would be curious to know what happens when you ash these, but not curious enough to acquire the gear just for this one experiment.

aliced25 - 12-3-2012 at 01:38

Here is some more - interestingly enough HCl or H3PO4 are the acids of choice for this procedure - with steam distillation being the preferred way of isolating the product from the 'strong' acid before it degrades too much (I suspect your choice of acid would be responsible for much of the charring).

What would be nice is a decent, completely otc route to THF, pyrrole, porphyrins, etc.

[Edited on 12-3-2012 by aliced25]

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Attachment: Hockett.Guttag.Smith.The.Production.of.Furfural.from.D.Lyxose.and.D.Ribose.pdf (299kB)
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Attachment: Youngburg.Studies.on.Pentose.Metabolism.II.A.Micromethod.for.the.Determination.of.Pentoses.and.Pentosans.pdf (354kB)
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niertap - 14-3-2012 at 21:19

Fructose will give one of the best yields. Acid catalyzed hydrolysis of sucrose should give a good supply of it. I don't really think anyone knows why frustose will give a 75% yield or something like that.

You may have to add a little silica jell, though. It seems to facilitate reactions with diols or more ols. When put through GCMS the polyols will kind of rip little bits of the column out.

however if you put any fructose containing mixture(ex. fruit juice) through it, the fructose will read as furfural.


I believe some organization was trying to find a great way to make it for use as an alternative fuel source. Fructose all the way.






Fructose


all the way

bbartlog - 15-3-2012 at 03:21

Quote:
Acid catalyzed hydrolysis of sucrose should give a good supply of it.


Under what conditions, using what acid? One possible outcome of such hydrolysis is levulinic and formic acids (and plenty of black gunk in an insoluble cake), per Organic Syntheses: http://www.orgsyn.org/orgsyn/prep.asp?prep=CV1P0335
Now maybe with less water, or a dehydrating acid (such as sulfuric acid), or other conditions... do you have a reference?