Study on the chromogenic reaction of ironII with reagent 4-(2-thiazolylazo)-1,2,3-trihydroxybenzene and its applications

A new reagent 4-(2-thiazolylazo)-1,2,3-trihydroxybenzene (TATB) was synthesized,and the chromogenic reaction of iron * with the new reagent TATB has been studied in the presence of Tween-40 by the spectrophotometric method in detail.The results show that in the medium of pH 8.0-9.0,iron* reacts with the reagent TATB to form a stable blue complex (1∶3).The maximum absorption of this complex is at 620 nm with an apparent molar absorptivity e_(620) of 4.30×10~4 L·mol~(-1)·cm~(-1).Beer's law is obeyed in the iron * concentration range of 0-30 μg/25 mL.The proposed method has been applied to the direct determination of micro amounts of iron in pure aluminium and aluminium alloy standard samples with satisfactory results.