Kinetic fluorimetric measurement of trace resorcinol in phenol mixtures.

A kinetic spectrofluorimetric method was studied to measure the concentration of trace resorcinol. The proposed method is based on the inhibitory effect of resorcinol on the oxidation of rhodamine B by potassium bromate in the medium of dilute sulfuric acid. The detection limit and linear range of the proposed resorcinol measurement method are 12 microg L(-1) and 24 approximately 280 microg L(-1), respectively. Relative standard derivations of eleven measurements for 80 microg L(-1) and 200 microg L(-1) resorcinol solutions are 2.12% and 1.08%, respectively. The trace of resorcinol can be determined directly by the proposed method without any pre-separation process when phenol and many other phenolic compounds are present.