Correlation between enrichment factor of deuterium and that of tritium by electrolysis using solid polymer electrolyte

摘要

For the purpose of improving the accuracy and precision of tritium measurements in environmental water samples, the new method for the estimation of tritium concentration before electrolytic enrichment was proposed in the previous paper. A new apparatus of tritium enrichment by electrolysis using solid polymer electrolyte was developed. Using the apparatus, we examined the fact that there is a reliable correlation between the enrichment factor of deuterium and that of tritium. The constancy of the ratio, k, during the electrolysis, k =#alpha#(#beta#-1), is obtained and k value is 1.173+-0.007, where a and #beta# are the separation factors of deuterium and tritium, respectively. The value of k is more stable than the values of #beta#/#alpha# and of log#beta#/log#alpha#. Using the k value. the initial concentration of tritium in water sample, (T/H)_0, could be estimated by the formula (T/H)_0=(T/H)_f/[(D/H)_f/ (D/H)_0]-(-k), where (T/H)_f and (D/H)_f are the tritium and deuterium concentrations after electrolysis. and (D/H)_0 is the deuterium concentration before electrolysis. It is not necessary to measure the water volume or weight before and after the electrolysis. When the deuterium concentrations before and after electrolysis are measured by mass spectrometer. the enrichment factor of deuterium becomes more accurate and precise.