References: 11 tit.

Chromium and iron speciation has increasing applications with regard to different objects of environment and biomedical materials. Topical issue is the development of a technique of simultaneous determination of chromium and iron. In this work the possibility of simultaneous spectrophotometric determination of chromium (VI) and iron (III) with help of the mixed organic reagent (diphenylcarbazide and 1,10-phenanthroline) is studied. We have applied curve fitting method to separate overlapped absorption spectrum of chromium (VI) and iron (III). Peak shape analysis of pure signals of complexes of chromium (VI) with diphenylcarbazide and iron (III) with the 1,10- phenanthroline is previously carried out. For adequate application of curve fitting method we chose the optimal empirical models of signals taking into account preliminary information on their shape. Correctness of determination of concentration by means of the offered technique is proved by "added-found" method for a series of mixtures with different ratios of concentration of chromium (VI) and iron (III). It is founded that the error of determination of concentration doesn't exceed 11%.