Separation of Gas Mixtures and Isotopes

Recently, however, the type of diffusion unit with a porous wall has been abandoned by Hertz and his collaborators (5i), and instead batteries of diffusion pumps are joined together directly, separation occurring by effusion together with mercury vapour through jets. The theory of the separation of 

This equation holds only when the pressure of diffusing gas is high. When the pressure and temperature are such that the densities of the diffusing gases are small compared with the density of the mercury vapour, one has D = wA (w = the molecular velocity yl = themeanfree path), and the expression for the separation of the isotopes becomes 

It was found in a liquid mixture a separation of up to 4 8% was established in two days— about of the equilibrium separation in the stationary state. The method was employed successfully to disproportionate the isotopes Zn, Zn g, Zn g, as aqueous solutions of zinc sul-phate(57). The isotopes were estimated spectroscopically. The method has also been used (59) in the separation of isotopes of Cl and of Hg. The method is of quite general applicability in disproportionating or sedimenting such mixtures as 

Na2S04 in H20(57), CgHg in CgH5Cl(57), Chlorophyll in CCl4(57), 

Original gas mixture /o Length of separating column cm. Temp. diflF. °C. Composition at  

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