两种快速测定锆铪的光度法

Two Quick Spectrophotometric Determination Method of Zirconium and Hafnium

研究了锆和铪的二甲酚橙络合物在高氯酸介质中、硫酸钠下存在的吸收光谱，结果表明：在高氯酸介质中，Zr（Ⅳ）-XO，λmax为555-558nm；Hf（Ⅳ）-XO，λmax为535nm。在常温下，Hf（Ⅳ）-XO在558nm和500nm处的吸光度比值稳定。对锫铪混样可用双波长K系数法测出锆的含量，用差减法求出铪的量，此法适用范围为锆（铪）0～250．g／25mL；在低温（0-5℃）时，有硫酸钠存在的条件下，铪被有效隐蔽，测出锆的含量，再结合EDTA滴定法可求出铪的含量，该法适用范围为锆0—30μg／25mL，铪0—40μg／25mL。两种测定分析方法的相对误差均在10％以下。

Studies were performed on the absorption spectra of the xylenol orange complex compound to zirconium and hafnium in the medium of perchloride acid dielectric and with sodium sulphate. The results showed that Zr - XO,λmax is 555nm; Hf（ Ⅳ ） - XO,λmax is 535nm in perchloride acid. And at room temperature,The Hf（Ⅳ） -XO absorbency ratio of 558nm to 500nm is steady. So the amounts of zirconium in the presence of hafnium can be determined by the double wavelength K coefficient, and that of hafnium can be obtained by subtracting from the zirconium and hafnium. The determination range of the method is 0 - 25 μg/25mL for zirconium and hafnium. In the low temperature（0 -5℃ ） ,with the existence of sodium sulfate,the hafnium can be masked,and zirconium can be determined. The quantity of hafnium can be got by the method of subtracting combined the EDTA complexing titration. It is available in 0 - 30μg/25mL for Zr（ Ⅳ ） and in 0 - 40μg/25mL for Hf（ Ⅳ ）. The relative errors of two determination analytical methods are both less than 10%.