Argon isotope separation

Fig. 8.9 (a) A four stage thermal diffusion cascade for argon isotope separation (Modified from Spindel, W. ACS Symp. Ser. 11, 82 (1975)). (b) The thermal diffusion cascade operated by K. Clusius and collaborators at the University of Zurich during the 1950s (Photo credit Archives of the Institute of Physical Chemistry, University of Zurich)... 

Ironically, our current plans call for the reverse linkage of the above enrichment procedures. That is, we shall use an electromagnetic isotope separator to enrich argon isotopes for a mass spectrometry experiment, and we shall enrich radiocarbon via thermal diffusion for improved mini-gas proportional counting. 

The essential difference between K-Ar and Ar-Ar dating techniques lies in the measurement of potassium. In K-Ar dating, potassium is measured generally using flame photometry, atomic absorption spectroscopy, or isotope dilution and Ar isotope measurements are made on a separate aliquot of the mineral or rock sample. In Ar-Ar dating, as the name suggests, potassium is measured by the transmutation of to Ar by neutron bombardment and the age calculated on the basis of the ratio of argon isotopes. 

Figure 4. Hot wire thermal diffusion cascade for separating argon isotopes (17)...

TO test the reactor and analysis system, pulses of methanol, singly, and completely deuterated methanol were led over the commercial Pe (MoO.) VtoO, catalyst and the two separate phases, m this way, we can check-3if a kinetic isotope takes place on the separate phases, and the measurements can be extended to a larger temperature range more readily than under steady state conditions. The pulses contained about 12% methanol in argon and 10% oxygen. 

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