新试剂7-(2,4,6-三羟基苯偶氮)-8-羟基喹啉-5-磺酸光度法同时测定微量锆和铪

Simultaneous Spectrophotometric Determination of Micro-amounts of Zirconium and Hafnium With a New Colour Reagent 7-(2,4,6-Trihydroxy-benzeneazo)-8-hydroxyquinoline-5-sulfonic Acid

本文研究了新试剂7-(2,4,6-三羟基苯偶氮)-8-羟基喹啉-5-磺酸(THBAQS)与锆、铪的显色反应.酸性条件下锆、铪均可形成 M-THBAQS-CTMAB三元络合物,ε_(315nm)^(Zr)=3. 27×10~4,ε_(515nm)^(HI)=3.8×10~4,适量H_2O_2使锆络合物吸光度显著降低,据此实现了锆铪的同时测定.本法简便快速、适用范围为0～30μgZr/25 mL,0～25μg Hf/25 mL,且X_(Zr)+X_(Hf）<35μg/25 mL.

The colour reaction of multicomponent complexes of Zr(Hf)-7-(2 ,4 , 6-trihydroxy-benzeneazo )-8-dydroxy quinline-5-sulfonic acid-CTMAB was studied spectropho-tometrically. It is shown that the complexes can be formed in acid medium, with Zr515nm of3. 27×104l · mol -1· cm-1 and Hf515nm of 3. 80×104L · mol -1· cm-1, respectively. Adding just right amount of hydrogen peroxide to the colour system, the absorbance of zirconium complex is reduced markedly and that of hafnium complex does not change basically when the two elements co-exist each other. So, a method of simultaneous spectrophtometric determination of micro-amounts of zirconium and hafnium has been developed. The determination range is 0-30 μgZr/25 mL, 0-25 μgHf/25 mL and XZr-XHf<35 μg/25mL.