Determination of micro amounts of resorcinol by inhibition kinetic spectrophotometry

A new inhibition kinetic spectrophtometric method for determination of micro amounts of resorcinol was proposed. It is based on the inhibitory effect of resorcinol on the discoloration reaction betwwen H 2O 2 and Rhodamine B catalyzed by Fe(Ⅲ) in dilute sulfuric acid solution. The optimum conditions and the kinetic parameters of this reaction were studied. The linear range of determination is 0.2～0 3 mg/L for resorcinol, e 564 =1 3×10 4 L·mol -1 ·cm -1 . The method was applied to the determination of resorcinol in water.