Ion Exchange Resin Online Separation-Atomic Absorption Spectroscopy System for Measuring Lithium Concentration in Primary Circuit Water Containing Boric Acid of Nuclear Power Plant

In pressurized water reactor nuclear power plants, the primary circuit water chemistry control uses the boron-lithium coordination solution. Under the existence of the boric acid in the primary circuit water, the lithium recovery significantly decreases with the increase of boron concentration by the method of atomic absorption spectroscopy. In this study, ion exchange resin online separation-atomic absorption spectroscopy system which used allochroic ion exchange resin to remove boric acid of the primary circuit water was developed. The system eliminates the effect of boric acid and reaches the accurate analysis of lithium concentration. Under the optimized conditions, boric acid is completely removed. The recovery of standard addition and relative standard deviation are 101.0% and 0.47% (n=6) respectively. The results demonstrate that the present system can be applied in lithium concentration analysis in the primary circuit water of nuclear power plants. The system has the advantages of simple structure, ease of building without the requirement of complexly fabricated devices, low cost, convenient operation and no pollution by the boric acid in burner of atomic absorption spectroscopy.