红外光谱法在线测量高浓度重水

为了准确、快速、安全定量工艺系统中的高浓度重水，采用离线式傅里叶变换红外光谱仪，以空光路状态下的单光束谱为背景光谱，得到不同浓度标准重水样品的红外吸收光谱，对3410cm^-1处重水浓度与吸光度进行线性拟合，建立红外光谱法测量高浓度重水的工作曲线。在此基础上，设计重水在线测量方案，实现高浓度重水在线测量。结果表明，测量浓度为99.85%的重水时，相对标准偏差优于0.01%。重水浓度范围为99.06%~99.98%时，线性相关系数R²=0.999 9。该测量方法准确、快速、无损样品、无放射性辐照等，可拓展到其他浓度段重水在线测量。

On-line Determination High Concentrate Heavy Water with Infra-red Spectrophotometry

High concentrate heavy water was used as moderator or coolant in a reactor, and its concentration directly effects the safety and performance of the reactor. The samples were generally taken from the process system manually and then analyzed with infra-red spectrophotometry in the laboratory off-line. This study was carried out to quantify high concentrate heavy water of process system accurately, quickly and safely. In this work, infra red absorption spectrum of different concentrations of standard heavy water were gotten on the Fourier infra-red spectrometer off-line, with the single beam spectrum of empty optical path as the background spectrum. A working curve between the absorbance at the wavenumber of 3 410 cm^-1 and concentrations of heavy water was established with linear function. On this basis, the program of high concentration heavy water on-line measurement was designed. The measurement method is accurate, rapid, non-destructive and without irradiation. For 99.85% heavy water concentration, the relative standard deviation was better than 0.01%. When the deter mined range of heavy water was 99.06%-99.98%, the linear correlation coefficient R² was 0.999 9. This method could also be extended to determine heavy water with other concentration ranges.