低压条件下气态UF_(6)纯度的红外光谱分析方法

FTIR Analysis Method for Purity Analysis of Gaseous UF 6 at Low Pressure

为建立低压条件下使用傅立叶红外光谱法定量分析气态UF_(6)的纯度方法,本研究选取1150 cm-1处的吸收峰作为定量分析UF_(6)纯度时的特征吸收峰。针对UF_(6)气体净化后尾料中UF_(6)残留量的在线分析需求,建立满足真空密封要求的红外分析系统、标准样品配比系统和背景图谱标定装置,对不同纯度、不同压力条件下的气态UF_(6)标准样品进行分析,建立UF_(6)纯度与其特征吸收峰面积、稳定压力相关的计算公式。结果表明,通过该方法可准确地得到60~140 Pa的压力范围内和0~100%的纯度范围内气态UF_(6)的纯度。建立的分析方法和计算公式满足低压条件下UF_(6)气体在线快速分析的要求。

In order to establish a method for quantitative analysis of the purity of gaseous Uranium hexafluoride using Fourier infrared spectroscopy under low pressure,the absorption peak at 1150 cm-1 was selected as the characteristic absorption peak for quantitative analysis of the purity of uranium hexafluoride.It was showed that the pressure of gas analysis has a direct effect on the area of characteristic peak under low pressure condition,which could not be ignored in the process of purity calculation.Aiming at the online analysis demand of the residual UF 6 in the tail material after UF 6 gas was purified,the gas standard UF 6 samples with different purity and pressure conditions were analyzed by establishing an infrared analysis system,a standard sample ratio system and a background spectrum calibration device that could meet the requirements of vacuum sealing.The calculation formula for the relationship between the UF 6 purity and its characteristic absorption peak area as well as the gas absolute pressure were established.The experimental results showed that the purity of gaseous UF 6 which was in the pressure range of 60~140 Pa and the purity range of 0~100%could be accurately analyzed by this method.