Sciencemadness Discussion Board

Magnetic Carbon?

tacromx - 21-2-2018 at 14:52

So the day before i cooked up some sugar and zinc chloride in a 1:1 ratio in de-ionized water, cooked at 500c for 3 hours and at the end i got a very light carbon structure which i powdered afterwards. I then blasted it 3 times for 10 seconds in my 800w microwave oven(sparkles and smoked quite a bit). Purely out of curiosity i wanted to see if it was magnetic,took a magnet to the bottom of the glass container and indeed it was!!. How can this be?, can anyone explain this to me?.

Thanks in advance.

elementcollector1 - 21-2-2018 at 15:10

Pyrolytic graphite responds to magnets, but I'm unsure if you managed to make that with such an unusual procedure. Did you really just throw all this together, or were you after some other end product?

aga - 21-2-2018 at 15:17

Likelihood % = 0. Damn.

Shame really.

Anyone with a furnace capable of maintaining 500 C for 3 hours could do a very wide range of interesting things.

Morgan - 21-2-2018 at 15:54

Could zinc chloride at 500c have leached iron or nickel from a vessel if a metal container was used? Or could the carbon have an electrostatic charge that may have responded to the magnet or other materials for no other reason than static attraction?

I was thinking the carbon being so light, that even traces of iron might be plenty to create an attraction.

"This invention relates to the removal of iron which is contained as an impurity in the ferrous state in aqueous solutions of chemicals, as in the manufacture of zinc sulfate and zinc chloride."
"In the manufacture of zinc salts the crude liquors contain varying amounts of ferrous iron, depending upon the source of the raw materials and the particular methods of operation."
http://www.freepatentsonline.com/2369270.html

[Edited on 22-2-2018 by Morgan]

tacromx - 21-2-2018 at 16:01

Since im mainly into battery research i needed a kiln for making activated carbons, so i made one. My procedure was exactly as described in my first post. I was not happy with the conductivity of my first batch and thought i might try it in the microwave, it has made the conductivity quite a bit lower(down to 32ohms from 823ohms).

Thanks for replying.



IMG_0128.JPG - 1.9MBIMG_0130.JPG - 1.8MB

Magnetic Carbon?

tacromx - 21-2-2018 at 16:04

@Morgan

Yes it was a metal container.

Guess ill have to invest in a graphite crucible to know for certain then.

thanks for the reply.


[Edited on 22-2-2018 by tacromx]

Melgar - 21-2-2018 at 16:45

Were you moving it through a magnetic field, or moving he magnet past it? Graphite is conductive, and theoretically would respond to a moving magnetic field in the same way that nonmagnetic metal particles would when moved through a magnetic field. THe effect would be minor, but with small particles suspended in liquid, you might be able to notice it.

edit: Have you tried making lampblack? That's how they used to make carbon particles back in the day.

[Edited on 2/22/18 by Melgar]

tacromx - 21-2-2018 at 17:10

@Melgar

I have the carbon in a 500ml borosilicate beaker, when i place a 10x10mm neodymium underneath touching the bottom and move it, the carbon particles move with the magnet, kind of like the old etchasketch toy, or iron fillings on paper. Must say as an active material on my aluminium/copper battery it has increased the runtime quite considerably.

Carbon black?, ill have to have a go at that if i can find instructions detailing the procedure.

I have tried a run at graphitic carbon nitride as well at 550c, but had to stop it after an hour because i over filled the container and the ammonium fumes became ridiculous at which point i started thinking about a change of underpants :D

I did however manage to get a yellowish brittle solid, have no idea if this is gcn or something else?

thanks for your reply.


[Edited on 22-2-2018 by tacromx]

BromicAcid - 21-2-2018 at 17:15

Magnetic biochar for cleaning water

https://pubs.acs.org/doi/suppl/10.1021/acs.jchemed.6b00154

Morgan - 21-2-2018 at 19:08

Another biochar tidbit
http://www.biochar-international.org/node/3833

Melgar - 21-2-2018 at 19:46

Black iron oxide is magnetic, and would be indistinguishable from carbon particles visually. I have a friend with more money than he knows what to do with, that fancies himself an alchemist. He somehow thought that he could get a form of rhodium by extracting it from grape juice. And that he could tell he had it when it responded to a magnetic field. (I know, I know. Bear with me.)

I saw the demonstration, and indeed there was a black powder that responded to a magnetic field. So I just immediately said "probably black iron oxide". He asked if there was some test he could do to confirm whether that's what it was. I had to think about it a little, but then realized adding hydrochloric acid to iron oxide should make it turn bright yellow, as FeCl3 forms. He did this, and indeed, it slowly turned yellow. He was disappointed, to say the least, and kind of in denial. So he asks "is there some other test I could do on it?" I'm like "yeah, you can see if it responds to a FUCKING MAGNET. Rhodium won't!"

To make lampblack, just light a candle or an oil lamp, and put the bottom of a glass beaker directly in the yellow part of the flame. The beaker should have room temperature water in it so the carbon on the glass doesn't burn. Don't get it so cold that water condenses on it out of the air though. Carbon builds up kind of slowly, but if you leave it and come back to it in like an hour, there will be a considerable amount. I'm not sure how much you need, and there are better ways if you need large amounts, but with this method you just need a candle and a lighter.

DrP - 22-2-2018 at 02:59

Quote: Originally posted by Melgar  


To make lampblack, just light a candle or an oil lamp, and put the bottom of a glass beaker directly in the yellow part of the flame. The beaker should have room temperature water in it so the carbon on the glass doesn't burn..... you just need a candle and a lighter.


Do you know if you can get any bucky balls out of that black? I have no idea how they are currently made, but I think they were discovered as a very, very small by-product of candle soot originally.

Sulaiman - 22-2-2018 at 04:59

Graphite is diamagnetic ... repelled from a magnetic field gradient.

I use either pyrolytic graphite (best) or graphite foil(cheap) to 'levitate' above neodymium magnets.

So the effect may look like the attraction of iron filings but is probably a repulsion.

You would have to move a magnet quite quickly to induce significant Lorentz force in graphite.

Even water is observably repelled by a powerful magnetic field gradient.

MrHomeScientist - 22-2-2018 at 06:32

Try just placing the magnet on the outside of the container, not moving it. If you tilt the container and particles stick to where the magnet is, they are magnetic to some degree. If they only respond to a moving magnet, it's likely a force generated by Lenz's Law. The former, to me, indicates iron contamination, and the latter could be from the carbon being conductive. Although I've never heard of carbon behaving this way, it would be interesting if it did.

What was the goal of your original experiment?

tacromx - 22-2-2018 at 08:26

It's contamination i suspect, tried a small sample in hydrochloric acid, as you can see from the picture its green/yellow, does this mean its iron?.

@Melgar, thanks for the recipe for the carbon black, going to try that.

I did put some powder on the table, paper on top and it did pick up most of the powder with a magnet stationery on top of the paper and lifting the whole paper and magnet.

Like i said im after a conductive carbon

Thank you all for your reply's

IMG_0134.JPG - 1.4MB

aga - 22-2-2018 at 08:54

Great photos - that's a really nice surprise !

Pyrolysing ordinary bread in a tin can in the middle of a small fire gives a conductive carbon material.

The last lot i made measures about 4 ohms across 10mm (simple multimeter test).

Oh. Forgot to say: Welcome to the ScienceMadness forum !

resist.jpg - 36kB

Edit:

i just tested that sample with a couple of strong magnets and it does nothing .

[Edited on 22-2-2018 by aga]

tacromx - 22-2-2018 at 09:42

Thank you Aga.

Ill try some bread in the kiln,any estimates as to temperature and time?

aga - 22-2-2018 at 09:58

Hard to say/know exactly - more experimentation needs doing.

I pyrolyse in a metal food can with a small hole in the top, using a wood fire.

It is 'done' when there is no more gas coming out of the hole, or the fire is finished.

A guess would be around 900C and 20 minutes.

tacromx - 22-2-2018 at 10:14

I think that's doable in my kiln, bricks are rated for 1260c and element is good for just over 1100c, ill try it for 30min and see what happens(clean underpants at the ready :D )

Thanks for your reply and advice.

aga - 22-2-2018 at 11:10

Best of luck !

Be sure to report the results here.

happyfooddance - 22-2-2018 at 11:25

This is a two-necked rbf that I ruined (but kept because it looks cool) making activated carbon from lime tree bark. I put a tall column on the flask, and connected the top of the column to a water aspirator. Heating element was a mantle for a 1000 ml flask. Had a blast shield because I had considered implosion. Didn't implode, but the softened borosilicate did invert itself.

The carbon was some of the best I've made.

20180222_111738.jpg - 650kB

aga - 22-2-2018 at 12:52

How on earth did that happen ?

happyfooddance - 22-2-2018 at 13:35

Lol, strong heat and vacuum, mi amigo!

NEMO-Chemistry - 22-2-2018 at 17:30

LOL might want to turn that mantel down a bit :P

happyfooddance - 22-2-2018 at 17:41

Quote: Originally posted by NEMO-Chemistry  
LOL might want to turn that mantel down a bit :P


You live and you learn.

ninhydric1 - 22-2-2018 at 17:55

The flask reminds me of a 600 mL beaker that I broke while washing. The whole bottom just fell out, leaving me with a hollow glass "tube." Nearly cut myself with the sharp edges.

EDIT: That was off-topic. To OP, its probably iron, maybe a bit of nickel and chromium if you used stainless steel. Graphite is a good option, or you would go with something less reactive, maybe copper if you can get a copper crucible.

[Edited on 2-23-2018 by ninhydric1]