Determinação espectrofotométrica simultânea de cobre e ferro em álcool etílico combustível com reagentes derivados da ferroína

In the present work three ferroin reagents were studied for the simultaneous spectrophotometric determination of iron and copper: 1,10-phenanthroline, 2,2'-bipyridine and 2,4,6-tri(2-pyridyl)-1,3,5-triazine. Effect of pH, conditions, order reagent addition, interferences, amount of reagents, lineal range, sensitivity and stability of each system were compared. The 2,4,6-tri(2-pyridyl)-1,3,5-triazine can be used for determination of iron in the presence of copper with a detection limit of 5 µg L-1 and coefficient of variation of 2.0%; However it was not possible to determine directly copper in...