5-Br-PADAP二波长联合分光光度法同时测定矿石中铌和钽

Simultaneous Determination of Niobium and Tantalum with 5-Br-PADAP by Two Wavelength Spectrophotometry

铌、钽的显色剂很多,但由于两元素性质相近,常互相干扰,特效的光度测定方法却不多,能同时测定的更少。5-Br-PADAP近年已成功地用于测定铌,测钽时则无法消除铌的干扰,有人分别测锟钼合量和锯后,差减计算钼,也有测定几个波长的吸光度后。

In H_(2)SO_(4) medium both Nb and Ta form complex with 5-Br-PADAP with maxium absorptions at 605 and 506 nm respectively.If the absorb ances of the complex mixture and the individual complexes are all measured at both 605 and 506 nm,the contents of Nb and Ta can be calculated easily with an electronic calculator.But the sum of the individual absorbances are not always in good congruity with the absorbance of the complex mixture.By regulation of the concentrations of the reagent and the complexing agent for Nb and Ta and adding alcohol to the solution the absorbances can be made in good congruity, and linear calibration curves can be obtained. The common elements such as Ti, Fe, Al, Sn, W, Mo, Zr, Mn, Ca, Mg, F^(-), Cl^(-) etc. do not interfere.