| Longer-lasting, inert and
carbon-free cathodes |
| Replacement of anodes consisting
of petroleum coke and tar pitch, consumed in the electrolysis in an
anode reaction |
| Use of renewable electrical
energy sources for electrolysis |
| Higher cell efficiency and
avoidance of cell freezing also for seasonally variable power availability
from renewable electrical energy sources |
| Electrolysis cell operation
under variable electrical power supply |
| Low-temperature electrolytes |
| Reduction of the cryolite
melting point |
| Use of red mud as a feedstock
resource instead of dumping |
| Less electrode reactions |
| Replace techniques of leaching
in an autoclave, calcination in a rotary kiln, and electrolysis in
cells with Söderberg anodes with the altogether up to 20% lower-energy
solutions of leaching in a tubular reactor, calcination in a fluidized
bed reactor, and electrolysis in cells with prebaked anodes |
