本法是用分光光度法测定六氟化铀水解液中的硅。对其中的氟离子用硼酸掩蔽。在0.3N盐酸介质中,使硅与钼酸铵生成黄色络合物,在草酸存在下用甲基异丁基酮萃取分离,当无水乙醇存在时,用氯化亚锡还原,生成硅钼蓝。以试剂空白做对照,在波长632 nm处,进行分光光度测定。本法的测定范围为0.5—5.0 μg/5 ml,其摩尔消光系数为1.1×10~4,精密度为3%,可检出3 ppm硅。 This method is the spectrophotometric determination of uranium hexafluoride hydrolyzate silicon. The fluoride ion is masked with boric acid. In 0.3N hydrochloric acid medium, the silicon and ammonium molybdate yellow complexes generated in the presence of oxalic acid with methyl isobutyl ketone extraction separation, anhydrous ethanol, with stannous chloride reduction to produce silicon molybdenum blue. Reagents blank control, at a wavelength of 632 nm at the spectrophotometric determination. The determination of the law range of 0.5-5.0 μg / 5 ml, the molar extinction coefficient of 1.1 × 10 ~ 4, the precision of 3%, can detect 3 ppm silicon.