1BP中铀钚价态及其含量的分析方法

建立了1BP工艺点铀钚价态及其含量的分析方法。通过研究不同价态铀钚的可见吸收光谱，采用多点斜率法拟合了不同价态铀钚在414、480、600、659 nm波长下的摩尔吸光系数ε。利用摩尔吸光系数ε结合多元线性回归法（MLR），建立了1BP中Pu(Ⅲ)、U(Ⅳ)、U(Ⅵ)及Pu(Ⅳ)分析的数学模型。该方法测量了1BP模拟样品：在工艺正常情况下，Pu(Ⅲ)的质量浓度范围为0.50～8.00 g/L，测量精密度优于3.0%(n=6)，回收率为94.5%～103.9%；U(Ⅳ)的质量浓度范围为0.45～38.15 g/L，测量精密度优于3.0%（n=6），回收率为95.3%～104.7%；U(Ⅵ)的质量浓度范围为0.45～38.59 g/L，测量精密度优于3.0%（n=6），回收率为96.5%～103.0%；Pu总量的回收率为87.2%～100.6%。方法简单快速，精密度高，属于无损分析。

Determination of Valence and Concentration of Uranium and Plutonium in 1BP Solution

A method was developed for determination of valence and concentration of uranium and plutonium in 1BP solution. Absorbance spectrum is exploited in determining the concentration of uranium and plutonium which coexist in several different valences. The molar absorption coefficients of uranium and plutonium in different valences and different wave lengths were fitted by slope method. By which, a mathematical model based on multiple linear regression(MLR) was evaluated for analysis of Pu(Ⅲ), U(Ⅳ), U(Ⅵ) and Pu(Ⅳ) in 1BP solution. A series of synthetic solutions which mixed up different concentration of uranium and plutonium solution were prepared for validating the method. The results show this method has great advantages of determining the valence and concentration of uranium and plutonium in 1BP solution: that Pu(Ⅲ) can be determined in range of 0.50-8.00 g/L and the recovery is 94.5%-103.9%, U(Ⅳ) can be determined in range of 0.45-38.15 g/L and the recovery is 95.3%-104.7%, U(Ⅵ) can be determined in range of 0.45-38.59 g/L and the recovery is 96.5%-103.0%. The relate standard deviation of all the measuring results are less than 3.0%(n=6). The recovery of total plutonium is 87.2%-100.6%. In a word, the method is simple, fast, highly sensitive and non-destructive.