235U enrichment by pulse gas diffusion


LIGHT-WATER nuclear reactors use uranium fuel enriched in isotope 235U. One of the enrichment processes is gaseous diffusion. This process is used in large-scale plants in the US and uses the fact that, in the Knudsen diffusion condition, 235UF6 diffuses through the porous membrane at slightly higher rate than 238UF6. A transient Knudsen diffusion process is proposed here which gives a higher enrichment factor for the lighter species compared with a steady state diffusion process. Because of the higher enrichment, the number of stages required for enriching 235U to a concentration level suitable for nuclear power reactor fuel is considerably reduced.

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WAKAO, N. 235U enrichment by pulse gas diffusion. Nature 278, 35–36 (1979). https://doi.org/10.1038/278035a0

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