alkaline metal drives?

There are places in the world where the salt concentration is already high enough to make any environmental impact from dumping more salt negligible.

That's not why I resurrected this old topic though.

I looked at a table for energy density, and noticed aluminium being very high on energy/weight and especially energy/volume compared to other substances. Hydrogen has great energy/weight ratio but poor energy/volume ratio. Would it be possible to use aluminium as fuel for an upper stage? Powdered aluminium mixed with some liquid fuel, perhaps? Or just liquid aluminium (melting point about 660 C)?

Kerosene fuels are often spiked with powdered aluminum. You can do the same with hydrogen, your ISP goes down but the density goes up quite a bit.

Under www.bernd-leitenberger.de it is mentioned that Lithium and Beryllium as well as their hydrides have very high ISPs.

They obviously can't applied in air and cause significant environmental pollution and are toxic. So on Earth they can't be used vby first stages.

They aren't researched much and would have to be used by hybrid drives.

I am not sure if Lithium shoud be consumed such a way - accumulators use them and what are the existing amounts on Earth?



Dipl.-Volkswirt (bdvb) Augustin (Political Economist)