分光光度法测定铂-铼催化剂中铼含量

Spectrophotometric Determination of Rhenium in Pt Re Catalysts

提出了用分光光度法测定重整催化剂中铼含量的方法。试样用盐酸、磷酸、过氧化氢溶解。溶液中的七价铼在盐酸介质中被氯化亚锡还原成二价铼，铼（Ⅱ）与硫脲形成稳定的黄色配合物。在吸收波长４４０ｎｍ 处测得表观摩尔吸光系数为５．６６×１０３Ｌ·ｍ ｏｌ－ １·ｃｍ － １。铼量在０～２０ｍ ｇ／Ｌ范围内符合比尔定律。用本法测定了重整催化剂中的铼，结果满意。

A spectrophotometric method for determining rhenium content in Pt Re reforming catalysts is reported in this paper. The sample is dissolved in hydrochloric acid, phosphoric acid and hydrogen peroxide. Rhenium(Ⅶ) is reduced to rhenium(Ⅱ) by stannous chloride in hydrochloric acid medium,then rhenium(Ⅱ) forms a yellow stable complex with thiourea. The molar absorptivity is 5 66×10 3 L·mol -1 ·cm -1 at 440nm. Beer's law is obeyed in the range of 0～20mg/L. The proposed method has been applied to the determination of rhenium in Pt Re reforming catalysts, the results are satisfactory.