A Molten Salt Reactor/Recycling

To help recycle radioactive rods and other toxic stuff a Thorium Reactor could help add energy while reducing the radioactivity of uranium after it has been used. The liquid in the reactor could be used over a 40 year or even more period. Recycle nuclear waste.
Maybe even use it to help recycle slag in a small way.
It could also be used medically for isotopes, though i could be wrong on that type of reactor.

In what way is that different to the current Fast Breeder Reactor?

This is in the game.

Also called salt dual flued reactor, china is building some of them right now.