采用取样量较少的离子色谱法测定了放射性废液中硫酸根含量.放射性废液先经稀释1 250倍,然后进行离子色谱测定.进样量为100 μL,将硫酸根标准溶液加入于试样基体溶液中制作工作曲线.试样的基体溶液系在放射性废液中加入钡离子使其中硫酸根完全生成硫酸钡沉淀除去后制成.由于采用了上述的高倍稀释方法,不但使废水样的放射性大大降低,而且还避免了溶液中共存的金属离子生成沉淀而堵塞色谱柱的干扰因素.分别在从两个试样制备的基体液中加入硫酸根标准溶液制作工作曲线,算得其相关系数分别为0.998 6和0.997 4,方法的检出限为18.9 μg·L-1.根据测量峰面积计算所得的相对标准偏差为1.46%,回收率试验的结果在96.7%~103.8%之间.

Ion-chromatography was appled to the determination of radiation waste water sample of radiation waste water was diluted 1 250 times and 100 μL of the diluted sample solution was introduced into the instrument for IC determination.Calibration curve was prepared by adding standard sulfate solutions of different concentrations to the matrix solution prepared from waste water sample after removal of the sulfate by precipitation with barium ion.By applying the high multiple dilution as described above,not only the radiation of the water sample was reduced to a great extent,but also the interference of precipitation of co-existing metal ions possible to clog the chromatographic column was eliminated.Correlation coefficients of 0.998 6 (sample matrix 1) and 0.997 4 (sample matrix 2) were obtained showing satisfactory linearity of the calibration curves.Detection limit of the method was found to be 18.9 μg·L-1.Precision was tested and the value of RSD (n=8) obtained by measuring the peak area was 1.46%.Recovery was also tested,giving values in the range from 96.7% to 103.8%.