Analytical Sciences

Effect of Temperature on HTO-Dissociation Determined by Ion Exchange Resins

Naoki KANO, Daisuke ARAI and Hiroshi IMAIZUMI

Department of Chemistry and Chemical Engineering, Faculty of Engineering, Niigata University, Ikarashi, Niigata 950-2181, Japan

In order to reveal the effect of temperature on (i) the dissociation equilibrium of tritiated water (HTO water) and (ii) the reactivity of each anion-exchange resin, the OT-for-OH exchange reaction between each anion-exchange resin and HTO water was studied within the range of 20^{¡¼/sup>C to 80¡¼/sup>C in the equilibrium state. In addition, the apparent dissociation constant (pK') for each resin was estimated by the method of pH-titration. From the observation of the OT-for-OH exchange reaction between each of the following anion-exchange resins and HTO water, the next three items have been found: (1) in the case of acryl-type anion-exchange resin, the effect of temperature on OT-for-OH exchange reaction is larger than that on the reaction in the case of styrene-type one; (2) the radioactivity incorporated into weakly basic anion-exchange resin (OH--form) by the isotope exchange reaction is smaller than that into strongly basic one; (3) in the case of the weakly basic anion-exchange resin, the amount of radioactivity incorporated into Cl--form resin by the hydrolysis is larger than the amount of radioactivity incorporated into OH--form resin by the isotope exchange reaction. (Keywords: OT-for-OH exchange reaction, anion-exchange resin, tritium, dissociation of tritiated water, apparent dissociation constant)}

J-STAGE: View this article in J-STAGE