Sciencemadness Discussion Board

sugar dehydration to carbon with alternatives....

charrd - 3-3-2017 at 19:34

howdy ya'll - i was dreamin' last night and figured i might wanna try a sugar - carbon err "synthesis" with "biologically" friendly compounds. I'm interested in creating carbon in bulk 50+ lbs...and surprisingly, sugar is a lot cheaper than "activated carbon" or "lump charcoal"

Anywho - N-P-K are all "garden" friendly....and there might be a few dehydrating compounds out there with these elements...

I'm wondering if I could add a conc. phosphoric acid to sugar to yield high purity carbon? I'm also wondering if anyone has any info in using "hot ceramics" as a dehydrating agent.

Last night I sorta envisioned using some sort of "phosporus" containing dehydrating agent used as a "catalyst" with the bulk dehydrating agent being....hrm bulk clay brick powder

H3P04
sucrose + ceramic ---------> carbon + CO + P04/whatever +etc........


Geocachmaster - 3-3-2017 at 20:22

If you wanted to try and make + purify carbon "just because," then dehydration is certainly an option. However, you wish to make it in bulk, i.e. in excess of 50 pounds, and for a cheaper price than commercial. I don't think this would be feasible. About three minutes of searching found this, 52 pounds for about $90. I don't know about a good source, but I think that you could find 50 pounds of sucrose for around $25, maybe a little less. Sugar isn't only carbon though, it's only approximately 42% carbon by mass. Add in the cost of dehydrating agents (there are many), along with your time/effort and it gets expensive. In addition, the setup to deal with more than 100 pounds of sugar at one time and the processing too would likely be huge and costly.

In short, you should just buy carbon if you need large quantities. It would not be worth your time or money to try and make 50+ pounds.

(Edit: fixed grammar)

[Edited on 3/4/2017 by Geocachmaster]

j_sum1 - 3-3-2017 at 21:17

Well, the classic is using concentrated sulfuric acid. I have not done the stoichiometry but equal volumes of H2SO4 and sucrose is about right. Then you need to crush, wash and dry.
If you happened to have tens of litres of free sulfuric acid lying around doing nothing then by all means it might be economical. Otherwise, simply buy your carbon normally or make your own AC from charcoal following standard procedures.

charrd - 3-3-2017 at 21:47

Well...hypothetically...there's a lot of phosphate mining and sugar refining going on in Florida. Cheap sources...


Anywho...if you had a ..."bathtub" - couldn't you just fill that sucker up with sugar and add the acid? ...Maybe on a drip system lol

The resultant carbon appears very fine, brittle and powdery....That is what attracts me to this....I'm NOT interested in using bulk sulfuric acid...concentrated or otherwise. bulk phosphorus ore? Now that I'm interested in...

Fluorite - 14-4-2023 at 00:30

the other day I was dehydrating sodium bisulfate to the pyrosulfate
and while it's molten I spilled some on a tissue paper that charred it like conc sulfuric
I think this would dehydrate sugar

Admagistr - 15-4-2023 at 08:42

Many years ago I insert a kilogram of glucose into a ten-litre flask and poured one litre of concentrated H2SO4 into the flask, a thick fog formed and the mixture blackened and foamed, but the carbon obtained had some smell, it is certain that it was polluted with organic compounds, probably also sulphur organic compounds.
The way to pure carbon would probably be to heat the glucose strongly in a vacuum or under argon and then boil it with some mineral acid,perhaps HCl...I have read somewhere that chemically pure carbon can be produced this way...

[Edited on 15-4-2023 by Admagistr]

clearly_not_atara - 15-4-2023 at 09:26

Pyrolysis would definitely be the method of choice for OP's desire of putting carbon in his garden (???). Using any sort of acid would likely leave some acidic residues in the product, which can have damaging effects on plant life.

But he posted this thread six years ago, so it's probably too late now.

Admagistr - 15-4-2023 at 14:01

Quote: Originally posted by clearly_not_atara  
Pyrolysis would definitely be the method of choice for OP's desire of putting carbon in his garden (???). Using any sort of acid would likely leave some acidic residues in the product, which can have damaging effects on plant life.

But he posted this thread six years ago, so it's probably too late now.


You are absolutely right, producing carbon in this way for gardening purposes is, shall we say, very impractical... I was following the main idea of producing pure carbon as a chemical element for general use and especially for the needs of amateur chemists, and I forgot that the questioner wants to use it in the garden... This is not a gardening forum:D, I apologize for my inattention... Traces of acid would have to be removed from the carbon by annealing.