Sciencemadness Discussion Board

Designing a sodium aggregate reaction cell

Chemguy5 - 11-7-2018 at 12:41

I want to improve on Nurd rage's soup can reaction cell in which he reacts sodium hydroxide and magnesium turnings to create sodium metal aggregate. I have access to welding equipment and all kinds of tools and materials to fabricate some sort of reaction vessel. Now as far as I know to improve the yield of sodium I would need to limit the amount of oxygen getting into the vessel as to not oxidize the sodium as it forms. I also have access to argon gas which I'm thinking I can incorporate into the reaction vessel some how giving it a continuous stream of gas as to create an inert atmosphere but this is the tricky part. I know all this isn't necessary and I can get good yields just using a soup can but I have some free time on my hands and I would like to attemp coming up with a design and would like to get some ideas from some of you here.

My idea is to take a large hollow cylinder some what bigger than a soup can so I can scale up the reaction, I will cap off the bottom by welding it to a sheet of metal. I need some ideas on how I should create the lid. I obviously need pressure to vent out the lid as the reaction progresses without letting oxygen back in. I was thinking of just drilling a small hole in lid to release pressure and also welding a small metal tube in the side of the vessel hooked up to an argon tank and some tubing and giving it a constant supply of argon. Is it neccasary to pump argon throughout the entire reaction or only after the initial reaction is over?

Any help would be great thanks.

MJ101 - 12-7-2018 at 07:48

Since you have welding gear, Perhaps you can take some ideas from the design of a pressure cooker.

I would suggest a pressure gauge of some kind, but the NaOH might eat it. Not sure.

Best of luck with your project. Please post pics when it's completed. :)


Vosoryx - 12-7-2018 at 08:16

This sounds like a great project.
Yes, please post pics both at completion and during construction/various testing phases.

walruslover69 - 12-7-2018 at 08:25

How do you plan on opening it? It sounds like you would have to cut it open to get the contents out.

If you wanted to you could just attached an oil bubbler or just a cheap one way check valve that you could attach to a tube bought at any major hardware store.

I think it would be much easier for you to do it in a closed container so you didn't have to worry about rigging a gas release. If I were doing it I would get a 3-4 inch diameter pipe with screw cap ends and just screw iron endcaps to each end so u can easily unscrew and open it when the reaction is done. If you use sodium oxide instead of hydroxide then there will be no gas evolved therefore you could do it in closed system without too much pressure being generated.

If you have a high temp forge/furnace then you can make your own sodium oxide by heating sodium carbonate.

XeonTheMGPony - 12-7-2018 at 17:11

I'd use a spring loaded check valve on the lid to vent pressure but keep atmosphere out, then vacuum break with the argon as the reaction will make it's own sweeping gas.