High-performance liquid chromatographic determination of selenium in coal after derivatization to 2,1,3-benzoselenadiazoles
High-performance liquid chromatography was examined for the determination of selenium after derivatization to 2,1,3-benzoselenadiazoles using 1,2-diaminobenzene, 1,2-diamino-4-nitrobenzene (NDAB), 2,3-diaminonaphthalene and 3,3′-diaminobenzidine as derivatizing agents. Elution was carried out using a mixture of chloroform and hexane, with ultraviolet spectrophotometric detection. The 2,1,3-benzoselenadiazoles were extracted into toluene. Linear calibrations were obtained for 0–4 µg of selenium in 10 cm3 of solution and the detection limits were 20–50 ng of selenium in 10 cm3 of solution. The method was applied to the determination of selenium in coal samples and a shampoo using NDAB as the derivatizing reagent in acidic solution.