Separative Diffusion in the Transient State. II. The Hollow Cylinder and the Hollow Sphere

Abstract

For the hollow cylinder and the hollow sphere the separation factor S can be obtained, as for the plate, by generalization from the dimensionless time τ. Separation factors for the plate and the spherical shell are given by the same function of τ. The outfluxes, and accordingly the separation factor S, are equal for centrifugal and centripetal diffusion processes. With increasing outer radius R ₂ and constant R ₂/R ₁, the equally separated output increases with the square of R ₂ for the cylinder and with the cube of R ₂ for the sphere, while the time for equal separation increases with the square of the barrier thickness in both cases.