Integral fast reactor

![Buildup of heavy actinides in current thermal-neutron fission reactors,[11] which cannot fission actinide nuclides that have an even number of neutrons, and thus these build up and are generally treated as Transuranic waste after conventional reprocessing. An argument for fast reactors is that they can fission all actinides.](/uploads/202501/20/Sasahara.svg3814.png)
![IFR concept (color), an animation of the pyroprocessing cycle is also available.[24]](/uploads/202501/20/Ifr_concept3814.jpg)

The integral fast reactor (IFR, originally advanced liquid-metal reactor) is a design for a nuclear reactor using fast neutrons and no neutron moderator (a "fast" reactor). IFR is distinguished by a nuclear fuel cycle that uses reprocessing via electrorefining at the reactor site.