Science Buddies: "Ask an Expert"

Hello! I want to make a desalinating water bottle. Now, my idea is to put electrodes on the sides of a water bottle, and put in some cation/anion resin in the water bottle and then conduct a electric current through a magnetic field and have the ions in salt water get trapped so the pure water goes to the bottom. Do you think this would work and if the magnetic field would generate enough electricity to attract the ions? Suggestions would be great!

Thank You!

Hello,

That sounds like a cool idea! I'm not sure producing the electric current from the magnetic field will be strong enough to electrolyze and split the water apart. You may want to connect wires to your electrodes directly to a power source like a battery. Other than that, I don't see any other problems with your design. Ask me any other questions and I'll try to answer them as best as I can. Good luck!

Thanks for answering! I want to develop this idea to help people at sea or when unlimited supply of energy is low so I don't want to use batteries. But, I don't want to make pure water (splitting water molecules), since in salt water there are salt ions (Na+ or Cl-) when i charge the electrode (with the magnetic field or something else), the ions will be attracted to each side and i might put something like activated carbon to trap them and the water goes down at the bottom. Would that work?

Hello,

So if you're trying to make electricity from the magnetic fields, how would you make the magnetic fields move to produce an electric current? I think your design could work theoretically with splitting the salt ions and moving the water through a filter, but I'm not sure how it would fair in reality. Why don't you research and create a test model?

I would probably make a simple electric generator like this one www.wikihow.com/Make-a-Simple-Electric-Generator and attach it onto the water bottle. When you said it wouldn't fair in reality, could you elaborate on that and why you think it wouldn't work? It would help me a lot to see the flaws in the project thank you!

Well, the thing is are you using water that's straight from the sea? If you are, then there are differently more ions than just sodium and chloride ions dissolved in the water. So even though you may have water that's free of sodium chloride which in reality may still have some sodium chloride in it still left, you'll have other ions in the water that you'll want to get rid of.

But, wouldn't the other ions also be attracted to the electrodes? Because ions are atoms with net charges so they would all be attracted. As for the pollutants and bacteria, i could create a filter that would block it out since those are already made. Or i could just so some simple filters for the pollutants like activated carbon. Do you think that would work? Any other possible problems?

Yeah, I guess so. Your idea seems like it could work. Why don't you just try it and troubleshoot it out if you have any problems?