A fissile isotope can readily undergo fission reaction, and a fertile isotope can be converted into a fertile isotope via neutron capture (this is how plutonium is made for nuclear bombs). Neutron capture is not part of the main waste reprocessing method [1], the neutron capture already happened in the reactor. Reprocessing separates the plutonium and other byproducts from the remaining uranium 235 fuel before the latter is re-used, no fertile material is being converted to fissile material.
So now I ask you: what relevance, at all, does the distinction between fissile and fertile material have with respect to magic_hamster's claims about the feasibility of waste reprocessing? That commenter claimed reprocessing was not feasible, I responded with dozens of examples of reprocessing being carried out. What does fertile vs. fissile have to do with this?
The relevance is that fertile material is not "partially spent fuel" in any extant fuel cycle.
First it does nothing to the fission products (which are the bulk of the radioactive waste by mass). Second turning U238, Pu240, Am241, and transuranics other than Pu239 into usable fuel has never happened without being a minor side-product of neutrons from a fissile source, and using the dregs of Pu239 that is <1% of the spemt fuel and <20% ofntue waste does not reduce the radioactivity of the waste, rather it makes it more dangerous because Pu239 is significantly less harmful than the result of putting MOX in a nuclear reactor, as is regular spent uranium fuel.
> The relevance is that fertile material is not "partially spent fuel" in any extant fuel cycle.
Nobody was ever talking about fertile material until you brought it up. Let's re-read the relevant part in the root comment shall we?
> As pointed out in the video re-processing the fuel gets all of the usable fissile material out.
We were always talking about recovering fissile material. "Partially spent fuel" refers to fuel rods that still contain some fissile material. I have no idea where you got the idea that "partially spent material" referred to fertile material, especially when the comment you're referring to explicitly mentioned recovering fissile material.
It will recover U235 from spent fuel and reduce the need to mine and enrich new uranium. Nobody ever suggested reprocessing somehow cheats entropy and creates unlimited energy. Can you point to where in the comment chain you feel like someone made the claim that reprocessing entirely eliminated the need to mine new uranium? It recovers a portion of otherwise wasted U235, and I don't see anyone claiming that it makes infinite energy. There's no motte and baily, your interjection about fertile vs fissile material was totally irrelevant.
> The big lie is calling it waste; "partially spent fuel" is more accurate
Which you doubled down on twice, before backpedalling and claiming you never meant that the *other* 99% of the waste wasn't waste and "partially spent" actually means "has a few leftover dregs that don't make a meaningful difference".
So now I ask you: what relevance, at all, does the distinction between fissile and fertile material have with respect to magic_hamster's claims about the feasibility of waste reprocessing? That commenter claimed reprocessing was not feasible, I responded with dozens of examples of reprocessing being carried out. What does fertile vs. fissile have to do with this?
1. https://en.wikipedia.org/wiki/PUREX