Influence of organic dispersant on nuclear grade anion exchange resin and their interaction behavior

Polyacrylic acid (PAA) was used as an organic dispersant in the secondary circuit of nuclear power plants, which could interact with anion exchange resin and affect its properties in the condensate polishing treatment system. This study investigated the kinetics, isotherms, and thermodynamics characteristics of PAA adsorption on anion exchange resin. The results suggested that the inhibition of PAA adsorption on resin can be achieved by lowering the PAA concentration and temperature. In addition, the adsorption reversibility and influence of PAA on anion exchange resin were discussed. The chemical desorption agent (NaOH) can desorb 94.10% of the adsorbed PAA on resin. The physicochemical properties of anion exchange resin changed little after adsorbing and desorbing PAA. Furthermore, the interaction feature between PAA and anion exchange resin was revealed through analyzing the stoichiometry and ATR-FTIR spectra, which was partial ion exchange and most attachment. This feature caused the weak binding force between PAA and resin. Therefore, PAA was easily desorbed from the resin and the exchange capacity of resin can be restored after the chemical desorption process. In conclusion, PAA had little influence on the properties of anion exchange resin and did not cause nonreversible organic fouling.