Abstract

Enriching Uranium Using Gasseous Diffusion Method

Gasseus Diffusion is a method to enrich percent composition of 235-U from 0,71% in natural uranium to be 3 – 5%. In this method, gaseous uranium hexafluoride is forced through semi-permeable membranes. This produces a slight separation between the molecules containing uranium-235 and uranium-238. By use of a large cascade of many stages, high separations can be achieved. It was the first economic enrichment process to be successfully developed.This process is based on the principle that in a closed box, all molecules have the same energy; therefore the lighter molecules, on average, travel faster than the heavier molecules. As a result, the lighter molecules strike the walls of a container more frequently than their heavier counterparts. If a portion of the container consists of a small hole large enough to permit the passage of individual gas molecules, but not so large that a mass flow-through of the gas can occur, then more light molecules than heavy molecules will pass out of the container, since rate of effusion (diffusion to outside the box) is proportional to the inverse square of the mass. The gas leaving the container is somewhat enriched in the lighter molecules, while the residual gas is somewhat depleted.