J Fluoresc (2007) 17:113–118 DOI 10.1007/s10895-006-0128-2 ORIGINAL PAPER Kinetic Fluorimetric Measurement of Trace Resorcinol in Phenol Mixtures Jing Fan · Tao Zhang · Jianhui Sun · Maohong Fan Received: 3 July 2006 / Accepted: 28 August 2006 / Published online: 22 September 2006 C  Springer Science+Business Media, LLC 2007 Abstract A kinetic spectrofluorimetric method was stud- ied to measure the concentration of trace resorcinol. The proposed method is based on the inhibitory effect of resorci- nol 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 µgL −1 and 24 ∼ 280 µgL −1 , respectively. Relative standard derivations of eleven measurements for 80 µgL −1 and 200 µgL −1 resorcinol solutions are 2.12% and 1.08%, respectively. The trace of resorcinol can be determined di- rectly by the proposed method without any pre-separation process when phenol and many other phenolic compounds are present. Keywords Kinetic spectrofluorimetric . Resorcinol . Rhodamine B . Waste water Introduction Phenolic compounds are highly toxic environmental pollu- tants, and seriously threaten human’s health. Phenolic com- pounds in environment come from different sources, includ- ing industrial wastewater, solid castoff of coal tar, coking factory, gasworks, paper mill, chemical plants, pharmaceu- J. Fan () · T. Zhang · J. Sun · M. Fan School of Chemical and Environmental Science, Henan Key Laboratory for Environmental Pollution Control, Henan Normal University, Xinxiang, Henan 453007, People’s Republic of China e-mail: fanjing@henannu.edu.cn M. Fan Center for Sustainable Environmental Technology, Iowa State University, Ames, IA 50011, USA tical industry. Because of their toxicities, some of pheno- lic compounds have been listed as control targets in many countries. Phenolic compounds are also poisonous organic pollutants. Therefore, many governments have spent a lot of effort in their detection and control. The currently used methods for determination of the phe- nolic compounds include 4-aminoantipyrine (4-AAP) [1] and gas chromatograph [2]. 4-AAP method can only be used to measure the total concentration of phenolic compounds and is not able to measure concentration of individual phe- nolic compound in a mixture, consequently, the toxicity of the mixture can not be exactly evaluated. Gas chromato- graph can only be used to determine monohydric phenols and chlorophenols [3–5]. Different phenolic compound possesses different environ- mental behavior and has different ecological effect and toxic- ity. The real waste samples typically contain several phenolic compounds, therefore, determination of concentration of in- dividual phenolic compound is particularly important and useful especially when a pre-separation is not necessary. Resorcinol is one kind of phenolic compounds with high toxicity. It can be easily absorbed through the gastric tract and human skin, which can cause dermatitis, catarrh, convulsion, cyanopathy, and even death [6]. The major methods for the determination of resorcinol that have already been reported are high-performance liquid chromatography [7–11] and gas chromatography [12, 13]. The separations of these methods are efficient, but require expensive instrument and therefore are expensive. Another resorcinol measurement method is ultraviolet-visible spectrophotometry [14, 15]. This method is convenient but its sensitivity is low. Therefore, there is a need for development of a sensitive, simple, quick and inexpensive method for determination of resorcinol. It is known that rhodamine B can be oxidized by potassium bromate in acidic media. This oxidation reaction destroyed Springer