"A sodium metal anode is placed in an organic electrolyte" - no - you need metallic sodium. this takes energy. you get some of that energy back as electricity and 'stored' in the hydrogen by letting it turn back into an ion and forming some carbonate.
The baking soda can be used along with waste water, and the brine from desalination plants to grow spirulina which also captures CO2 and can be used to produce biofuels.