Sciencemadness Discussion Board - Reduction of Silicon Dioxide with Lithium

Reduction of Silicon Dioxide with Lithium

Chemistry Alchemist - 25-8-2011 at 05:38

Ive been collecting elements for a while and ive got a few reductions i wanna do and the most reactive element i can find so far is lithium, is it possible to reduce Silicon Dioxide with Lithium?

4Li + SiO2 = 2Li2O + Si

Is this a good route to getting silicon? i have no other silicon salts to work with

Oh and would i be able to use crushed silica gel? ive been collecting quite a bit of them

Bot0nist - 25-8-2011 at 05:46

If your Silicone dioxide is fine enough mesh, it can be reduced with aluminum in a thermite. You may need a little Al/S mix to get it going. Search the forum, and there are also a few good Utube videos on the reduction of SiO2 with aluminum.

Note, the resulting silicon will not be pure, but can be purified fairly easily IIRC.

Edit:spelling.

[Edited on 25-8-2011 by Bot0nist]

MrHomeScientist - 25-8-2011 at 05:46

I'd think that would work, but how were you going to mix the reactants together? Lithium won't last long in air before tarnishing.

I've done this through a thermite reaction. Here's my video of the process: http://www.youtube.com/watch?v=73YmP_JSrlU

The real reaction between Al and SiO2 is extremely difficult to get to work, so you add sulfur and extra aluminum as a booster, to provide extra heat to keep things going. I'm sure crushed silica gel would work better than the beach sand I used, since it's much more pure. That's one of the things I've wanted to try, but never got around to it. I did make pure SiO2 in another of my videos and that worked great in a thermite, so I imagine silica gel would be similar.

Chemistry Alchemist - 25-8-2011 at 05:52

ill just spread the SiO2 onto lithium foil and role it up tightly and ignite it in a tin can so that it can all react... lithium is way to soft to make a powder out of it, oh and MrHomeScientist, ive seen ur video 100's of times, love it... i don't have any source of aluminum or magnesium powder, that's why id rather use lithium and the way lithium burns, it reaches 1/2 the temperature of a thermite burning in open air... enclosed may be a different story

MrHomeScientist - 25-8-2011 at 06:00

Thanks! Glad to hear you enjoyed it

You wouldn't happen to be toothpick93 would you? He was also asking me about arsenic trioxide recently.

Your plan with lithium sounds reasonable to me. I don't see why that wouldn't work. Give it a shot, I'm interested to hear the results! If it ends up not working, all you've wasted is a battery and some free silica gel

User - 25-8-2011 at 06:05

And how about the old fashion reduction with carbon at high temp, I guess ridicilous temperatures.

SiO2 + 2 C → Si + 2 CO
My suspicion is right, its in the range of 1,900 degrees Celsius.
(according to wikipedia)
Would be cool to perform something like this at home, with a home built arc furnace this is possible.
Hot and scary

Another method suggested is molten salt electrolysis, this is could be difficult to do at home.

[Edited on 25-8-2011 by User]

Chemistry Alchemist - 25-8-2011 at 06:05

Yeah u guessed right, its me, how should i reward you? make a mini ground lampare this week end haha, yeah ill see what i can do and give it a shot on making the silicon, its actually a few battery, there is about 1 gram of lithium in a battery, so if you want a good yield a few grams would be needed, ill record and post what i get if i have time to do it and hope it works

... so u looked at my other post on arsenic trioxide? yeah Google isnt very good for telling me what i want to here so instead i can ask on here and get pretty reasonable answers

Chemistry Alchemist - 25-8-2011 at 06:09

My only route to get a high temperature like that is to make a mini furnace with bricks, put some wood in the middle, poor napalm on top and light it up, napalm burns at really high temperatures and it may work if not with silicon production but will for other elemental production with coke

IrC - 25-8-2011 at 06:12

You could try burning Mg in sand.

User - 25-8-2011 at 06:12

Really?
What temperatures do you achieve with this method?

blogfast25 - 25-8-2011 at 06:15

SiO2 + 4 Li === > Si + 2 Li2O

… is thermodynamically feasible but only just. The Heat of Formation (HoF) of SiO2 is - 905 kJ/mol (NIST web book) and for Li2O the HoF is - 599 kJ/mol (NIST web book). So with Hess Law the Standard Heat of Reaction becomes:

ΔRR, 298 K = - (- 905) + 2 x (- 599) = - 293 kJ/mol

Assuming (almost certainly rightly) that entropic effects are small (ΔS ≈ 0) then:
ΔG = ΔH - TΔS ≈ ΔH, so with ΔG < 0 we know the reaction is thermodynamically feasible (but this says nothing about how to achieve this reaction).

- 293 kJ/mol is not a high value though and in all likelihood there won’t be enough heat to obtain the reaction products in the molten form. Instead you’d obtain Si powder, embedded in lithium oxide. Extracting the Si from there could be tricky: Li2O forms water soluble LiOH but strong alkalis attack Si vigorously.

As mentioned above, the standard method for making technical Si (Note: NOT solar or chip grade!) once used to be the reaction of sand (SiO2) with Al powder and sulphur. Here’s one I made earlier:

http://developing-your-web-presence.blogspot.com/2007/10/sil...

Al powder is quite easy to obtain.

Chemistry Alchemist - 25-8-2011 at 06:16

i just looked it up on Google and a few posts said about 1900 deg Celsius and others said over 2670 deg Celsius

blogfast25 - 25-8-2011 at 06:16

Quote: Originally posted by User

Really?
What temperatures do you achieve with this method?

Not high enough: just google the insanely high MP of MgO (magnesia)...

blogfast25 - 25-8-2011 at 06:18

Quote: Originally posted by Chemistry Alchemist

i just looked it up on Google and a few posts said about 1900 deg Celsius and others said over 2670 deg Celsius

What temperatures are you now talking about?

Wizzard - 25-8-2011 at 06:19

I wouldn't want to waste good Lithium

I'd imagine the thermite method with aluminum in a fine powder with a drop area for the heated results should get the job done.

Chemistry Alchemist - 25-8-2011 at 06:21

Quote: Originally posted by blogfast25

Quote: Originally posted by Chemistry Alchemist

i just looked it up on Google and a few posts said about 1900 deg Celsius and others said over 2670 deg Celsius

What temperatures are you now talking about?

Burning Napalm

Chemistry Alchemist - 25-8-2011 at 06:22

Quote: Originally posted by Wizzard

I wouldn't want to waste good Lithium

I'd imagine the thermite method with aluminum in a fine powder with a drop area for the heated results should get the job done.

I don't have any Aluminum or magnesium powder unfortunately, that's why i have to use lithium for it, and anyways once i get a job, i can just buy more battery's, dismantle them and bam... lithium

blogfast25 - 25-8-2011 at 06:24

Quote: Originally posted by Chemistry Alchemist

Burning Napalm

Oh dear, we've got a wannabe commedian on our hands. Considering the sort of nonsense and other fallacies you've been spouting here so far, I'd suggest you try and put your 'serious hat' on, okay?

Bot0nist - 25-8-2011 at 06:25

I am not sure of your location, but Mg and Al powder is easy to source online, and much, much cheaper than buying and destructing lithium batteries.

[Edited on 25-8-2011 by Bot0nist]

Chemistry Alchemist - 25-8-2011 at 06:26

Quote: Originally posted by blogfast25

Quote: Originally posted by Chemistry Alchemist

Burning Napalm

Oh dear, we've got a wannabe commedian on our hands. Considering the sort of nonsense and other fallacies you've been spouting here so far, I'd suggest you try and put your 'serious hat' on, okay?

what do u mean by that?

blogfast25 - 25-8-2011 at 06:31

Quote: Originally posted by Chemistry Alchemist

what do u mean by that?

Read it again: it's not rocket science.

Bot0nist - 25-8-2011 at 06:37

Are you talking about gelled gasoline with Styrofoam aka 'kewl napalm'? Probably not the best way to reach high temps in a homemade furnace. Why not a carbon fire with a bellows or O2 injection? Would that be hot enough with good insulation I wonder

Chemistry Alchemist - 25-8-2011 at 06:39

yeah thats the napalm im talking about, i dont have the right tools to make a proper furnace, thats why i suggested the napalm... worst part is, napalm burns and produces a black soot residue and people may be asking questions to why black smoke is coming from my back yard

Otter - 25-8-2011 at 06:44

Quote: Originally posted by Chemistry Alchemist

yeah thats the napalm im talking about, i dont have the right tools to make a proper furnace, thats why i suggested the napalm... worst part is, napalm burns and produces a black soot residue and people may be asking questions to why black smoke is coming from my back yard

It's obvious you don't really know what you're talking about... wood fires don't even melt copper on the best of days and you start thinking you can use flaamethrower fuel?

Now it's usually easier to achieve such high temperatures with an electric arc. If you want to purify silicon in small quantities like a gram or so for fun you could just try to use graphite electrodes and a car battery.

Bot0nist - 25-8-2011 at 06:44

"worst part is, napalm burns and produces a black soot residue and people may be asking questions to why black smoke is coming from my back yard"

That's not the worst part.

[Edited on 25-8-2011 by Bot0nist]

blogfast25 - 25-8-2011 at 06:49

This is one of the funniest things I’ve ever read on this otherwise fine forum.

Lemmesee, so you’re going to extract some Li foil from batteries (you don’t know how hard that is and how little Li you get but never mind…) to react it with silica by pouring ‘kewl napalm’ on the assembly. Not ‘kewl’… You’re making me p*ss myself with laughter!

All this when you can have a nicely controlled self-sustaining reaction from fine sand, Al powder, some garden grade sulphur and two plant pots.

Next project: turn rat poison into arsenic metal, with or without napalm. Not that funny anymore…

You need help alright but of a different type...

Chemistry Alchemist - 25-8-2011 at 06:54

yeah thats true, you can get 3rd degree burns with this stuff, it is pretty nasty shizz, but if know how to handle it or what u are doing then it shouldnt the that bad...

theflickkk - 25-8-2011 at 07:18

A possible source of aluminum is to obtain tiny flakes of aluminum from aluminum paint. It may work but I'm not certain. There are sites online documenting this although I reckon the yields aren't extremely good. Nonetheless, cheaper than ripping apart lithium batteries.

Chemistry Alchemist - 25-8-2011 at 07:20

yeah i heard u can get aluminum powder for repairing car radiators but haven't came across it, and you could also just put aluminum foil in a coffee grinder a few times, that will make fine aluminum, tho i haven't invested in one yet

Lithium from Batteries

redox - 25-8-2011 at 07:21

Quote: Originally posted by blogfast25

Lemmesee, so you’re going to extract some Li foil from batteries (you don’t know how hard that is and how little Li you get but never mind…) to react it with silica by pouring ‘kewl napalm’ on the assembly.

It is actually really easy to get lithium from batteries if you know how to do it. I take a Dremel to the middle of a battery and cut it while I rotate the it. Once you can smell the iron sulfide, then you're done. Then simply pull the two halves apart and unroll the lithium. I have disassembled about six batteries in ten minutes using this method.

Chemistry Alchemist - 25-8-2011 at 07:34

Quote: Originally posted by blogfast25

http://www.youtube.com/watch?v=naCb20Zuueo

it doesnt look like i had any trouble on extracting lithium does it

sternman318 - 25-8-2011 at 07:50

Quote: Originally posted by Chemistry Alchemist

yeah i heard u can get aluminum powder for repairing car radiators but haven't came across it, and you could also just put aluminum foil in a coffee grinder a few times, that will make fine aluminum, tho i haven't invested in one yet

http://alphachemicals.com/30_micron?b=1
easy, reputable supplier. They also sell sulfur

blogfast25 - 25-8-2011 at 07:58

Quote: Originally posted by Chemistry Alchemist

http://www.youtube.com/watch?v=naCb20Zuueo

it doesnt look like i had any trouble on extracting lithium does it

Hey, congrats, you know?

So how much did you get there and at what cost?

Extracting Li foil from a virgin Li battery is a bit of fun but not much more than that...

Chemistry Alchemist - 25-8-2011 at 08:03

you get about 1 gram per battery, where i live its expensive and can be brought a bit cheaper in other places tho

blogfast25 - 25-8-2011 at 08:24

At over £7/gram battery lithium could be used for far more interesting purposes like reduction of rare earth fluorides.

Neodymium salts are quite easy to get from (cheap) neomagnets and can be easily converted to insoluble NdF3, although you really need to know what you're doing when using fluorides.

Li foil can be used in a layered design (Pu was first made from PuF4 + 4 Li this way), alternating layers of Li with layers of the fluoride. This could be heated in a crucible until reaction starts (it then sustains itself, producing liquid metal and liquid LiF). But some kind of hood or extraction system would be needed...

Chemistry Alchemist - 25-8-2011 at 08:34

Quote: Originally posted by blogfast25

Neodymium salts are quite easy to get from (cheap) neomagnets and can be easily converted to insoluble NdF3, although you really need to know what you're doing when using fluorides.

I like where ur coming from... but how would i preform this? crush the magnet and lay it on the lithium, roll the lithium up to enclose the magnet powder and light it up? would'nt it be contaminated to what else is in the magnet? and also would'nt working with fluorine salts be bad due to fluorine being so reactive?

theflickkk - 25-8-2011 at 08:54

There's a video by TheChemlife on youtube, titled "Turning magnets into chemicals"

blogfast25 - 25-8-2011 at 09:08

Quote: Originally posted by theflickkk

There's a video by TheChemlife on youtube, titled "Turning magnets into chemicals"

Yes and there are several threads on extracting Nd salts from neomagnets on this forum...

Chemistry Alchemist - 5-9-2011 at 21:52

Ses Silicon react with Dilute Sulfuric Acid?

Chemistry Alchemist - 5-9-2011 at 23:36

Reduction of Silica Gel With Lithium works, only got a small yield due t only having 1.4 grams of lithium but the reaction went well and just reacting any left over lithium with water and sulfuric acid

Chemistry Alchemist - 8-10-2011 at 00:19

Hey i preformed the experiment a while back but just now uploaded it, worked well link just below if u wanna check it out

http://www.youtube.com/watch?v=k7POuNmbX-8

blogfast25 - 8-10-2011 at 11:17

CA:

A few things. When claiming one has made this or that, it’s customary to include some evidence that what one made is indeed this or that.

Manganese metal is highly reactive when fresh: it even reacts with water (forming hydrogen). If you can dissolve what you claim is manganese and make an acid solution of it do the tricks we know manganese salt solutions do then your claim would be stronger.

Ditto silicon. Silicon does not really react with acids, strong or weak. But it does react with alkali. So your silicon should react with washing or caustic soda, strong enough, forming silicate (SiO3 (2-)) and hydrogen. Add acid to the silicate solution and silica drops out of solution.

You claim the silicon was molten: that’s a highly dubious claim. The MP of silicon is 1414 C, that’s white heat. Also the reaction SiO2 + 2 Li === > Si + 2 Li2O isn’t energetic enough (standard enthalpy of reaction at 298 K = - 296 kJ/mol) to reach such scorching end conditions…

The reaction between Li metal and NaOH is:

NaOH + 2 Li === > Na + Li2O + ½ H2

But seeing the colour of the Na D lines doesn’t mean there was any elemental sodium formed: just stick some NaOH in a flame as watch!