CFC a byproduct in uranium enrichment process?

We were on debate tournament this saturday debating on the motion “Renewable sources of energy are a better choice than nuclear energy in fight against climate change”. When we were the opposition, the other team claimed that CFC (chlorofluorocarbon) gases are a byproduct in uranium enrichment process.

Now as far as my knowledge of chemistry goes, I believe chlorine, fluorine and carbon have nothing to do with uranium, yet we’re talking not about chemical reactions, where, broadly speaking, only relations (bonds) between elements are changed, but about a change in a nuclear state of a particular element.

And whenever there’s a change in the nuclear state of a element, it can itself transform into another element, something that occurs in nuclear reactions with fission. Does that happen during the enrichment process too?

Only that way it would make sense that CFC emerged from this process. But it’s still slippery slope to me.