Thermonuclear plants provides 17% of the electrical energy used in the United States. Clearly, nuclear power is the future and the alternative to fuel. There are many R&D carried out in extracting energy efficiently from nuclear reactors and also scaling down the size of nuclear reactors and development of nuclear microbatteries to power small devices.

I am trying to understand the gist of how the LWR nuclear reactor operates. It involves UO2 rods arrange in bundles to heat up water.

Fission of U-235 can be induced by bombarding it with slow neutrons. U-235 undergoes fission to produce 2 daughter nuclei and 3 nuetrons. For civilian use, it is important to ensure that the uraninium rods are maintained at its critical mass, whereby only 1 neutron from each fission reaction attack another U-235 nucleus.

The thingy here is that only U-235 is fissible, not U-238. Uranium exist as 0.7% U-235 and 99.3% U-238. The UO2 is enriched industrially by centrifugation to remove U-238 to increase the proportion of U-235 to 3.5%. The fission reaction described by the above paragraph only works for U-235, so what happen to the rest of the uranium, ie. U-238?

Does nuetron from the fission reaction of U-235 attack U-238 to produce P-239? Plutonium 239 is known to be fissible. If we can convert U-238 to P-239, does nuclear fuel enrichment plants equip with capabilities to convert U-238 to P-239? Otherwise, alot of U-238 will be throwned away. The energy from U-238 can be harnessed by converting it to P-239

Centrigation is the current industrial method to seperate U-235 and U-239. However, a more modern techniques employs gaseous diffusion of UF6 to seperate the 2 isotopes. Why is the former technique more preferred? Centrifugation is definitely WWII technology, borned out of the renowned Manhatten Project. Why isnt the gaseous diffusion technique catching on? Gasesous diffusion is so much more faster..