What Is Called Nuclear Waste Is Mostly Fuel for Molten Salt and Fast Reactors

Unused fuel (aka nuclear waste) can be used as fuel in fast reactors like old fast reactors and molten salt nuclear reactors. Uranium 238 can be fissioned in any nuclear reactor that generates fast neutrons. * Fast neutron reactors also can burn long-lived actinides which are recovered from used fuel out of ordinary reactors.

Source: www.nextbigfuture.com