采用分光光度法测定钼精矿焙烧样中铼的含量。优化的试验条件如下：①测定波长为426 nm；②在盐酸（1+1）溶液中显色；③ 350 g·L^-1硫氰酸钾溶液的用量为1.0 mL；④ 20 g·L^-1氯化亚锡溶液的用量为1.0 mL；⑤硫酸的用量为3 mL；⑥加热温度为85℃；⑦加热时间为1.5 h；⑧铼试剂的用量为1.0 mL；⑨样品溶液的pH为9左右。铼的质量浓度在3.0~30.0 mg·L^-1内与其对应的吸光度呈线性关系，方法的检出限（3s/k）为1.0 mg·L^-1。方法应用于钼精矿焙烧样的分析，测定值与电感耦合等离子体原子发射光谱法测定结果相符，测定值的相对标准偏差（n=7）为1.1%~2.2%。用标准加入法进行回收试验，测得回收率为94.0%~106%。

Spectrophotometry was applied to the determination of rhenium in roasted sample of molybdenum concentrate. The optimized conditions found were as follows:① wavelength of determination was 426 nm; ② coloration in HCl (1+1) solution; ③ amount of 350 g·L^-1 potassium rhodanate solution was 1.0 mL; ④ amount of 20 g·L^-1 stannous chloride solution was 1.0 mL; ⑤ amount of H₂SO₄ was 3 mL; ⑥ heating temperature was 85℃; ⑦ heating time was 1.5 h; ⑧ amount of rhenium reagent was 1.0 mL; ⑨ pH of the sample solution was about 9. Linear relationship between values of absorbance and mass concentration of rhenium was obtained in the range of 3.0-30.0 mg·L^-1, with detection limit (3s/k) of 1.0 mg·L^-1. The proposed method was applied to the analysis of roasted sample of molybdenum concentrate, giving results in consistency with the values obtained by ICP-AES with RSD's (n=7) in the range of 1.1%-2.2%. Test for recovery was performed by standard addition method, giving values of recovery in the range of 94.0%-106%.