乙醇存在下偶氮胂Ⅲ分光光度法高选择性测定锆(铪)

HIGHLY SELECTIVE SPECTROPHOTOMETRIC DETERMINATION OF ZIRCONIUM(HAFNIUM)IN ETHANOLAQUEOUS SOLUTION WITH ARSENAZO Ⅲ

在含乙醇40％的4.3mol/L盐酸体系中,偶氮胂Ⅲ与锆(铪)形成灵敏的高次配合物(1∶3)。在665nm处测得摩尔吸光系数εZr=1.49×10~5,εHf=1.53×10~5,相当于水溶液灵敏度的2—3倍。本方法具有很好的选择性,可用于直接测定合金中微量锆(铪)。方法简便、快速、可靠。

Zr(Hf) forms a 1:3 complex with arsenazo Ⅲ in a 40％ ethanol acidic solution.The apparent molar absorptivity of Zr complex is 1.49×10~5 L·mol^(-1)·cm^(-1) at 665nm. Many diverse ions do not interfere with the determination of Zr.Uranium and thorium up to 0.03mg can be tolerated.The method of spectrophotometric determination of Zr has been established.It can be applied to the direct determination of Zr in aluminium alloy,magnesium alloy and copper alloy with satisfactory results. The method for simultaneous determination of Zr and Hf is also discussed.