4%, The anion colurn ts composed of Nalcite SR resin, 20-50 mesh, ‘arid measures 52 em in length and 11 mm inside diameter. It 4s conaitioned prior to use by washing with 50 ml of 10 per cent NaOH followed by 300 ta 500 ml of H20. The frection collected in step 3 1s added to the anion column in aliquots of 10 ml, permitting the column to drain to the top of the resin bed after each adjition (Note &). | The container used to collect the fraction is washed with 2 ml portions of H20, and the washings are added to the column. . Ss A distilled 420 reservoir is connected to the anion column 6. The 70 ml fraction is transferred to a beaker which contains and a flow rate of 1.0 to 1.5 ml/min is maintained. The first 15 ml -of eluate are discarded. The next 70 ml containing the sodium are collected. , 70 mg of fine mesh Dowex-50 (not colloidal), The slurry is stirred intermittently for 20 to 30 minutes to adsorb all the sodium on the resin. 7. ‘The resinis filtered on Whatman #50 paper, washed with 10 ml ef ethanol and 10 ml of ether, anc. sucked dry on a vacuum line. The resin is then mounted onan aluminum plate for counting (Note 5). A.9 NOTES Conditioning may be carried out using large batches of resin rather 1. than treating the analytical columns separately. 2. The flow rate was initially restricted to 0.5 ml/min but the 3. Prior to making up the anion column, the resin can be slurried inereasa to 1.5ml/min had. no adverse effects. ‘with a dilute solution of phenoIphthalein. The phenolphthalein is absorbed on the resin and indicates when the resin is in the hydroxide form. . _& A much better practice is to boil the cation fraction down to a few ml before addition to the anion column. 5. The chemical yield is 100 per cent. UNCLASSIELED