Sciencemadness Discussion Board

sodium carbonate from table salt

pinxsy - 27-2-2012 at 06:51

I tried to produce sodium carbonate from table salt without any liquid involved.
Here is the reaction:
2NaCl(s) + 1/2 O2(g) + CO2(g) -> Na2CO3(s) + Cl2(g)
Is it even possible?
If yes, is there any catalyst to make the reaction go fast?
I need the reaction to be below 1500C as this is how high my smelter can go and cannot hold any liquid.

I need help really.. Please give me any advice or suggestion.
Tq in advance.

AirCowPeaCock - 27-2-2012 at 07:03

Want sodium carbonate..try heating baking soda to something like 200 C..its alot easier, even if your reaction would work, and I doubt it--maybe if you compressed the gasses to 100 atm and then lowered it slowly to 0 atm. Does H2CO3 exist in the vapor phase?--that might be another expensive inefficient way to produce Na2CO3

pinxsy - 27-2-2012 at 07:43

But baking soda is expensive itself :(
I try using NaCl because i want to produce Na2CO3 in large scale.

How do you come into conclusion that the gasses needs to be compressed?


blogfast25 - 27-2-2012 at 07:44

Quote: Originally posted by pinxsy  
I tried to produce sodium carbonate from table salt without any liquid involved.
Here is the reaction:
2NaCl(s) + 1/2 O2(g) + CO2(g) -> Na2CO3(s) + Cl2(g)
Is it even possible?
If yes, is there any catalyst to make the reaction go fast?
I need the reaction to be below 1500C as this is how high my smelter can go and cannot hold any liquid.

I need help really.. Please give me any advice or suggestion.
Tq in advance.


Search for old patents. Even if you can get this to work (I'm very doubtful) it's an expensive way to produce a chemical that's cheap as chips and totally OTC.

Regards thermodynamical feasability, you need to calculate overall Gibbs Free Energy change (Delta G) at reaction temperature to get an idea of that...

The BP of NaCl is 1413 C but well below that it's fairly volatile and will get everywhere, especially when fluxing gas through it.

[Edited on 27-2-2012 by blogfast25]

ScienceSquirrel - 27-2-2012 at 07:58

I suspect that sodium carbonate can be bought cheaply almost everywhere.
Have a look in your local supermarket or hardware shop for washing soda.
The original suggested reaction is ridiculous. I doubt it would occur under any conditions.

AirCowPeaCock - 27-2-2012 at 08:03

Quote: Originally posted by pinxsy  
But baking soda is expensive itself :(
I try using NaCl because i want to produce Na2CO3 in large scale.

How do you come into conclusion that the gasses needs to be compressed?




Read a chemistry book. Le Chatelier's principle.

AirCowPeaCock - 27-2-2012 at 08:08

What makes you think it worked..?

pinxsy - 27-2-2012 at 08:10

AirCowPeaCock: the reactants are not all gases in this case though, mmm... solid NaCl is involved and pressure is pretty much negligible for solid. Since the BP of NaCl is as high as 1413C, temperature needs to be around that high for NaCl to turn gas first before Le Chatelier's principle actually takes effect. I am just hoping to turn NaCl(s) -> NaCl(g) around 800C, haha, if that is possible.

pinxsy - 27-2-2012 at 08:12

cause we did the whole experiment and we got the product

AirCowPeaCock - 27-2-2012 at 08:20

Quote:
2NaCl(s) + 1/2 O2(g) + CO2(g) -> Na2CO3 + Cl2(g)


I see gaseous reacting and products, kind sir. It would be more accurate to write it like this though.

4NaCl(l) + O2(g) + 2CO2(g) <-> 2Na2CO3(l) + 2Cl2(g) at 1 atm

Count the moles of gas.

What makes you think you have the product, do you have super eyes and can see the individual molecules in the material?

pinxsy - 27-2-2012 at 08:29

AirCowPeaCock: Sadly, yes i do not have super eyes, how i wish! But from color we can differentiate between for example, Fe and rust...

and thank you for further explaining the Le Chatelier's, it will be a good idea to try!

Hexavalent - 27-2-2012 at 08:51

If you want sodium silicate, you may just be better using saturated NaOH on SiO2 or even some old, clean glass.

Also, I have to agree with all of above. I went to the store yesterday and bought a whole kilogram of sodium carbonate, quite pure, for less than $1.50.

[Edited on 27-2-2012 by Hexavalent]

pinxsy - 27-2-2012 at 08:56

Thank you Hexavalent.

Really appreciate to u all!

AirCowPeaCock - 27-2-2012 at 08:57

Nice, what kind of store sells you Na2CO3? I know wine/beer making stores sell it, is their another place? I just make mine from baking soda, its not that bad, after I make it I know its anhydrous already.

What back-round in chemistry do you have pinxsy?


[Edited on 2-27-2012 by AirCowPeaCock]

Hexavalent - 27-2-2012 at 12:11

I just went to the supermarket and found the Na2CO3 on the washing products aisle, labelled as 'Washing Soda'. The list of ingredients on the back says '99% Sodium Carbonate', which is good enough for my purposes.

Whilst I was there, I also picked up half a kilo of sodium sesquicarbonate, the double salt of Na2CO3 and NaHCO3, as a fabric softener.

AirCowPeaCock - 27-2-2012 at 12:26

Interesting, I'll look into that. Thanks

Morgan - 27-2-2012 at 18:19

I bought a large bottle of sodium carbonate for pH adjustment in the pool supply area of a store like Lowes or Home Depot. Just another source.

AirCowPeaCock - 27-2-2012 at 19:25

Thanks, I may get off my baking soda habit. Do you think it comes anhydrous?

Hexavalent - 27-2-2012 at 23:15

I'm jealous of you Americans and your pool supply stores . . .here in the UK it's insanely difficult to get hold of NaBr or sodium bisulfate OTC!

AirCowPeaCock - 28-2-2012 at 07:45

It's not that great, the NaBr has some junk in it to make it difficult to achieve pure HBr. And I haven't found bisulfate, though I haven't looked that far. I just make it from my sulfuric acid and sodium hydroxide--its probably cheaper that way anyways. You should be jealous of a L of 94-98% H2SO4 for 2$ and a pound of NaOH for 3$. How hard is it to get KMnO4 over there?

Hexavalent - 28-2-2012 at 10:18

The only place I've found, short of chemical suppliers, is eBay!:)

AirCowPeaCock - 28-2-2012 at 10:26

eBays great. I got a pound of technical grade MnO for something like 5$--the only real uses I have for manganese compounds (besides permanganate) are as catalysts, so it will last me for ever.

[Edited on 2-28-2012 by AirCowPeaCock]

Morgan - 28-2-2012 at 19:58

I have a can of this in my garage. The front label says it contains sodium bisulfate. Just another source.
http://www.contenti.com/products/soldering/510-871.html
http://www.krohnindustries.com/71101.html

For all your crown-of-thorns starfish needs.
http://en.wikipedia.org/wiki/Sodium_bisulfate